Tesis sobre el tema "Nutritional Scienes (Theses)"

Thesis (MPhil (Animal Sciences))--University of Stellenbosch, 2004.
African Grey Parrots are now being bred on a commercial scale in South Africa, mainly for the export market. In order to produce the best breeding results it is necessary to formulate balanced diets but no research has been done on the feeding value for African Grey parrots of ingredients used in formulating diets. Once the apparent metabolisable energy (AME) of extruded maize for African Greys has been established it will be possible to calculate the AME of other ingredients such as full fat soya, soya oil cake or sunflower oil cake. By feeding an extruded mix containing a known amount of maize mixed with a known amount of soya oil cake and establishing experimentally the AME of the mix, the AME of soya oil cake for African Greys can be calculated by difference. This information will make it possible to decide whether AME results obtained for poultry can be used in formulating diets for African Grey parrots. The study consisted of two parts where the determination of the apparent metabolisable energy (AME) of extruded maize and the practical application thereof in formulating parrot diets, and the economic viability of a commercial African Grey parrot breeding operation was investigated. A reference procedure adopted by several European laboratories for the in vivo determination of metabolisable energy (ME) was used to determine the apparent metabolisable energy (AME) of extruded whole maize for African Grey parrots. The long term goal is to make a well balanced, extruded diet for these birds. Extruded maize is the form in which maize is generally included in commercial parrot diets and was therefore chosen as the experimental feed. Maize can be conveniently extruded with other single ingredients such as full fat soyabean meal, soyabean oil cake meal or sunflower oil cake meal to determine, by difference, the AME of those ingredients. For the first part of the study, ten, 3-year-old African Grey parrots were individually housed and fed in cages designed to facilitate collection of the faeces. Cage design varied between a tall type (n=6) and a low type (n=4). The parrots were acclimatized to their new environment before the trial commenced to ensure normal feeding behaviour. The average AME value established for the ten African Grey Parrots was 16.8 MJ/kg. In the trial it became apparent that it is very difficult to get consistent results with the cages used and a modified cage design is proposed for the future. The second part of the study investigated the economic viability of breeding African Grey parrots commercially, with extruded maize as part of their diet. It was generally concluded that the breeding of African Grey parrots for the pet market can be considered as an economical venture.

Feed mills demand routine techniques to analyze digestible amino acids in highly variable animal meals. As routine tools, infrared spectroscopic predictions of digestible amino acids require reference samples assayed in vivo. Lack of reference samples resulting from costly and time-consuming in vivo assays has limited infrared spectroscopic applications. To remove this limitation, an in vitro assay mimicking in vivo digestion in swine was sought as a replacement to build the reference database.

Pepsin and pancreatic proteases used in the in vitro assays produce autolysates that are assayed as digestible amino acids. To correct this contamination and define incubation time for efficient use of the proteases, the autolysis of these proteases was studied. Correction of enzyme contamination with enzyme blank incubations and incubation time of 24 hours for pepsin and 96 hours for pancreatic proteases were proposed (Chapter III and IV).

In vitro digestion focused on maximal hydrolysis of peptide bonds with minimal enzyme usages for restriction of enzyme contamination. The minimal enzyme usage was determined to be 6.5% (enzyme to substrate ratio) (Chapter V).

Study on absorption of peptides in swine revealed that all soluble in vitro peptides could be estimated as digestible in vivo. Average in vitro digestibility coefficients were comparable to in vivo for a number of amino acids but mismatch occurred for individual samples. In vivo digestible amino acids, though, could be predicted with in vitro digestible amino acids. For example, lysine was predicted with an error of 0.27% (Chapter VI).

Total and digestible amino acids were predicted with near infrared reflectance spectroscopy (NIRS) and mid infrared Fourier transform infrared spectroscopy (FTIR) but not with Raman spectroscopy. Infrared spectroscopic prediction errors for digestible lysine were 0.27% for near infrared spectroscopy and 0.26% for mid infrared spectroscopy. Total amino acids seemed better predicted than digestible amino acids by infrared spectroscopy (Chapter VII).

The study showed that as routine techniques, infrared spectroscopy could potentially replace both in vivo and wet chemical analyses of amino acids.

Nutritional and energetic needs of female mammals depend upon size or reproductive investment and shape individual activity budgets and behavioral patterns. To maximize nutritional and energetic intake females may increase time allocated to foraging or access resources through risk-prone behaviors, represented as aggression or leadership. Conversely, to minimize nutritional and energetic spending females may engage in risk-averse activities such as resting or nonaggressive social interactions. Females with the highest needs should exhibit activities and behaviors that facilitate the greatest nutritional and energetic returns or highest metabolic savings. The propensity for risk-prone behaviors may be greater among older as well as lactating females. Older individuals tend to be larger and more experienced than younger conspecifics. Moreover, lactating females are under substantially greater energetic, nutritional and water stresses than nonlactating individuals. Therefore, to fulfill greater nutritional and energetic needs, older and lactating females may allocate more time to foraging or rest or be more assertive during search for and defense of resources. I assessed the relative effects of age, reproductive condition and sex of nursing offspring on activity budgets, the frequency of risk-prone and risk-averse behaviors such as leadership propensity, and chemosensory inspection of the surroundings in female African savanna elephants (Loxodonta africana africana). To quantify activities and behavioral patterns I used focal animal sampling with continuous recording. I determined leadership by the position in a mobile herd, where the first and last positions were considered as ends, and the center was considered as a middle position. I discovered that older females stood more, were more aggressive, socialized less and traveled closer to the end of a traveling group than younger females. Females that were lactating spent more time foraging, were more aggressive and engaged in nonaggressive social interactions less frequently than their nonlactating conspecifics. Finally, females nursing female calves spent more time foraging than females nursing male calves, but the latter spent more time nursing and standing. These results elucidate how individual nutritional and energetic needs influence the activity budgets as well as the propensity to exhibit risk-prone and riskaverse behaviors in female elephants and thus add to a body of work examining mammalian female activity budgets shaped by individual differences such as age and reproductive condition.

Thesis (M.S.)--East Tennessee State University, 2004.
Title from electronic submission form. ETSU ETD database URN: etd-0329104-095404. Includes bibliographical references. Also available via Internet at the UMI web site.

Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide, chloropicrin, and 1, 3-Dichloropropene. Additional treatments included ozone gas (six treatments) and biological control (three treatments). Collected data included total plant yield, individual berry weight, number of fruit produced per plant, plant vegetative weight, infection status, and mineral concentration of fruit (calcium, magnesium, potassium, iron, zinc, manganese, carbon, and nitrogen). Plants grown in ‘clean’ soil were less likely than plants grown in ‘infested’ soil to be infected with Verticillium. Plants grown in soil treated with MB had higher plant weight and yield than did non-treated control. Ozone and biological control treatments did not have statistically higher yield than non-treated control plants nor statistically lower yield than plants grown in soil treated with MB. Individual berry weights had a narrow range while the number of berries produced per treatment had a wide range. Data suggests strawberry yield is dependent on the number of berries produced per plant. Plants with high vegetative weight produced the highest yield suggesting large plants produce many berries resulting in higher yield.

Current research shows moderate alcohol consumption is associated with decreased risk of diabetes and excessive consumption or binge drinking can cause insulin resistance and diabetes. In 2010, diabetes was the seventh leading cause of death in the United Statesand was responsible for significant health complications: blindness, kidney failure, and limb amputations, and is a large national economic burden. Fasting blood glucose (FBG) is a tool used to help diagnose diabetes. Abnormally high FBG, ≥100 mg/dl, is indicative of diabetes and pre-diabetes. Few studies have observed diabetic prevalence among young adults or college students. Studying young adults can help provide added information about early risk factors for diabetes and pre-diabetes, facilitating public health efforts to stem the rising tide of the diabetes epidemic. This study aimed to research the associations between alcohol consumption (numbers of days alcohol consumed in the past month and binge alcohol consumption in the past month) and FBG in a college population as part of the FLASH cohort study. FBG levels were measured in 141 young adult participants and alcohol consumption was determined by self report. Other individual-level characteristics and potential confounding variables were also collected. The association between alcohol consumption and FBG followed a J-shaped curve whereby students who reported drinking 6-8 days within the last 30 days showed significantly lower FBG levels than those who did not drink and those who consumed alcohol on nine or more days (p=0.04). Binge drinking did not have a significant association with FBG (p=0.4). Sex and body mass index were also significantly associated with FBG. In conclusion, moderate frequency of alcohol consumption is found to have an inverse relationship with FBG and excessive drinking can reverse these effects.

The nutritional value of faba beans (Vicia faba), Australian sweet lupins (Lupinus angustifolius), white lupins (Lupinus albus) and peas (Pisum sativum) grown in New Zealand for broilers were evaluated in terms of their nutritional characteristics, protein quality (protein efficiency ratio), apparent metabolisable energy, apparent ileal digestibility coefficient of amino acids and the effects on bird performance. The effects of dehulling and extrusion cooking on the nutritive value of legumes were also investigated. The first experiment discussed in Chapter 3 evaluated the effect of cultivars on the nutrient profile and protein quality of chickpeas (Cicer arietinum), Australian sweet lupins, peas and soybeans (Glycine max). With the exception of white lupins, cultivars had no effect on the proximate and fibre composition of grain legumes. Starch was the primary carbohydrate component of chickpeas and peas, whilst non-starch polysaccharides were the major carbohydrates in lupins. The legume proteins were deficient in lysine, methionine, cystine and threonine. No differences were found in protein quality between cultivars of the different grain legume species. The lowest weight gain and protein efficiency ratio, in addition to the highest relative pancreatic weight and mortality rate was found in raw soybeans, suggesting that soybeans contained high a concentration of anti-nutritional factors, such as protease inhibitors. Birds fed chickpeas, lupins and peas had a low mortality rate and relative pancreatic weight, confirming that the level of anti-nutrients in these legume seeds was low. The apparent metabolisable energy and apparent ileal digestibility coefficient of amino acids of faba beans, Australian sweet lupins, white lupins and peas were determined in the second experiment (Chapter 4). Cultivar effect on the apparent metabolisable energy values was observed only for faba beans and white lupins. Faba beans, white lupins and peas had comparable apparent metabolisable energy values, but these values were higher than those of Australian sweet lupins, and lower than that of soybean meal. No cultivar differences were found in the apparent ileal digestibility coefficient of amino acids of grain legumes. The apparent ileal digestibility coefficient of amino acids of both lupin species was found to be comparable to that of soybean meal. The effects of feeding diets containing 200 g/kg faba beans, lupins or peas on the performance, digestive tract development and litter quality of broilers were investigated in the third and fourth trials. In the cage trial (Chapter 5), the results showed that the weight gain of birds fed diets containing grain legumes was similar to that of control diet. Feed intake and feed per gain of birds fed diets containing the majority of grain legume cultivars did not differ from those fed the maize-soy diet. Birds fed diets containing faba beans had more dry and friable excreta compared to other treatment diets. The performance of birds fed diets containing 200 g/kg grain legumes during the 35 d grow-out period, in the floor pen trial (Chapter 6), confirmed the results of the cage trial. In this trial, weight gain and feed per gain of birds fed diets without meat meal were superior to those with meat meal. In cage trials, the modification of some segments of digestive tract development was probably due to the dietary NSP. Whilst in floor pen trial, digestive tract development was not influenced by the inclusion of grain legumes. The effect of methodology of determination (direct vs. difference method) on the apparent ileal digestibility coefficient of amino acids of wheat, maize, Australian sweet lupins, peas and soybean meal for broilers was evaluated in the fifth study (Chapter 7). The influence of methodology on apparent ileal digestibility coefficient of amino acids was found to vary amongst the feed ingredients. In general, the apparent ileal digestibility coefficient of amino acids of test ingredients determined by the difference method was higher than those determined by the direct method, suggesting that the use of the direct method may underestimate the apparent ileal digestibility coefficient of amino acids in low and medium protein ingredients. Data reported in Chapter 8 shows that dehulling increased the apparent metabolisable energy values of faba beans and Australian sweet lupins, but it had no beneficial effect on peas. The increase of apparent metabolisable energy values may be attributed to the decrease in non-starch polysaccharides of these legume seeds after dehulling. The removal of hulls increased the amino acid concentrations, but it had no effect on the apparent ileal digestibility coefficient of most amino acids. These results suggest that dehulling of grain legumes would be nutritionally beneficial and, likely to be economical in view of the improved amino acid concentrations and energy values. The final experiment (Chapter 9) demonstrated that extrusion of peas markedly influenced the content of crude protein, non-starch polysaccharides, starch, and trypsin inhibitors. The soluble non-starch polysaccharides and trypsin inhibitor contents of the majority of extruded pea samples were higher than those of raw peas, but insoluble and total non-starch polysaccharides decreased with extrusion. Extrusion had no effect on the apparent ileal protein digestibility and the apparent metabolisable energy of peas, but it increased ileal starch digestibility.

The prevalence of non-alcoholic fatty liver disease (NAFLD) in children has increased over the past decades, creating a need for animal models that recapitulate the features of the pediatric disease. Iberian pigs have a leptin-resistant phenotype characterized by hyperleptinemia, hyperphagia, and extreme adipogenesis. We hypothesized that neonatal Iberian pigs fed a high fat high-fructose (HFF) diet will develop a pattern of liver injury resembling pediatric NAFLD. In addition, we sought to determine if a mixture of probiotics would prevent the disease. Animals were fed 1 of 4 diets containing (g/kg body weight × d) 0 g fructose, 11 g fat and 199 kcal (CON-N; n=8), 22 g fructose, 16 g fat and 300 kcal (HFF2-N; n=8), CON + probiotic (CON-P; n=6), or HFF2 + probiotic (HFF2-P; n=6) every 6 h for 70 d. The probiotic mixture (6.2 × 104 cfu/mL) contained Pediococcus acidilactici, Pediococcus pentosaceus, Lactobacillus plantarum and Bacillus amyloliquefaciens. Body weight was recorded every 3 d. Serum markers of liver injury and dyslipidemia were measured on d 40 and 65 at 2 h post feeding. Fasting leptin, insulin, glucose and homeostatic model assessment (HOMA) values were assessed on d 70. Liver and skeletal muscle (longissimus dorsi) were collected on d 70 for histology, triacylglyceride (TAG) quantification, relative gene expression, and Western blot analysis. Metabolomic analysis was performed on liver tissue and plasma. Body weight was not significantly greater in HFF fed pigs compared to CON. Leptin, alanine and aspartate aminotransferases, alkaline phosphatase, lactate dehydrogenase and total bilirubin were increased (P ≤ 0.001), and high and low density lipoproteins decreased (P ≤ 0.05) in HFF2-N and HFF2-P. Livers in HFF2-P and HFF2-N had higher relative weight and TAG (P ≤ 0.001), micro and macrovesicular steatosis, ballooning degeneration, Mallory-denk bodies, inflammation and necrosis, increased gene expression of TNFα, TGFβ, IL1α and PPARγ (P ≤ 0.001), and decreased ChREBP (P ≤ 0.001). A probiotic affect was seen as pigs fed CON-P and HFF2-P had higher insulin and HOMA values were increased (P ≤ 0.05). Western blot analysis showed dysregulation of autophagy in liver of pigs fed CON-P and HFF2-P, and in skeletal muscle of pigs fed CON-N and HFF2-N. Metabolomic analysis demonstrated dysregulation of one-carbon metabolism, the tricarboxylic acid cycle (TCA), the urea cycle, and amino acid metabolism of pigs fed HFF2 diets compared to CON diets. In conclusion, Iberian pigs fed a HFF diet recapitulate many pediatric NAFLD-associated features, in the absence of obesity and independently of probiotic supplementation, suggesting a potentially suitable model for pediatric NAFLD research. Furthermore, probiotic supplementation did not ameliorate the onset of NAFLD when fed in conjunction with a HFF diet.

Thesis (PhD(Agric))--Stellenbosch University, 2011.
ENGLISH ABSTRACT: Exogenous fibrolytic enzymes (EFE) as additives in ruminant feeds are being researched worldwide. Promising effects on dry matter intake (DMI), digestibility and production in especially dairy cows, but also feedlot steers and even sheep have been observed. However, lack of or negative effects are also reported and the need arises for clarity on the mode-of-action of EFE. Forages are characterised as being highly heterogenic and contain varying concentrations of fibre. The fibre, in turn, varies greatly in digestibility, due to the chemical as well as anatomical build-up of this complex carbohydrate. Fibre, however, presents a major source of potential energy for ruminant animals and EFE is a viable option to increase the digestibility of forages. Therefore, a study with the aim of establishing whether EFE can affect the digestibility of forages, how it affects the digestibility and the clarification of the mode-of-action was drafted. From the literature, the first objective was readily attained and clear indications exist that EFE can indeed improve animal performance when their diets are treated with such enzymes. From the current study, it was shown that EFE can alter the rate and extent of gas production of certain forages (lucerne, kikuyu and weeping love grass) and also improve the in vitro digestibility thereof (P < 0.05). This is in agreement with other research findings and it was concluded that these effects were likely exerted during the early stages of digestion. A complete feed for sheep, when treated with the EFE, showed positive effects on the in sacco digestibility, as well as on the digestion kinetics of the feed (P < 0.05). The in vitro digestibility of the complete feed was also improved due to EFE treatment (P < 0.05). The observations on in vitro digestibility were less marked when a purified xylanase, obtained from the partial purification of the EFE cocktail, was used as the sole fibrolytic enzyme treatment. It is apparent, therefore, that enzyme specificity plays a major role in obtaining positive effects on digestibility of forages and feeds. In agreement with the literature, it is proposed that the approach to improve the digestibility of forages should be to use EFE cocktails containing various enzymes, matching the complexity of the substrate. The major aim of the study was, however, an in depth investigation of the mode-of-action of EFE. This aim was approached by observing changes in plant tissue material at the histological level upon treatment with EFE and incubation in buffered rumen fluid. Results showed that EFE had subtle, yet significant effects on cell wall material for the various tissues studied (P < 0.05). The major effect observed here was that EFE had a thinning effect on the cell wall thickness (P < 0.05). It was deduced that as EFE affected the cell wall of the plant material, earlier access by microorganisms could be achieved. Also, nutrients caught in the cell wall matrix could then be released for digestion. Therefore, observations that EFE increases the rate of digestion, as well as the extent of digestion of not only fibre, but also protein, were explained by the enzyme’s action on cell wall material. It was concluded that there is definite merit in the use of EFE to improve the digestibility of ruminant feeds and that this is partly related to effects on the cell walls of the forages. The effects can be expected to occur during the early stages of digestion, thereby potentially increasing the passage rate of digesta from the rumen. Additionally, the effect of the EFE is not limited to fibre and increased digestibility of all nutrients can be expected, thereby increasing the overall digestibility of the feed. Future research should further elucidate the mode-of-action of EFE using advanced technologies routinely employed in the plant sciences. Additionally, the main potential advantage of EFE treatment lies in improving the digestibility of poor quality roughages. Unfortunately, this is an area where limited positive effects are observed and in depth investigations should be undertaken to classify the specificity and optimum conditions of EFE to better match the complexity of the substrate being treated.
AFRIKAANSE OPSOMMING: Eksogene fibrolitiese ensieme (EFE) word tans wêreldwyd ondersoek vir die gebruik daarvan as voerbymiddels vir herkouers. Belowende effekte op DMI, verteerbaarheid en produksie van vernaam melkbeeste, maar ook voerkraalbeeste en selfs skape is al gerapporteer. Swak en selfs negatiewe effekte word egter ook waargeneem en daarom is ʼn deeglike ondersoek na die metode van werking van EFE van belang. Ruvoere word gekenmerk deurdat dit heterogeen van aard is en bevat variërende vlakke van vesel. Vesel maak op sy beurt ʼn wesenlike deel uit van die ruvoer, maar varieer baie in verteerbaarheid weens die chemiese sowel as anatomiese samestelling van hierdie komplekse koolhidraat. Ruvoer verteenwoordig egter ʼn goeie bron van potensiële energie vir herkouers en EFE word voorgestel as ʼn haalbare behandeling om die verteerbaarheid daarvan te verhoog. Dus is ʼn studie beplan met die doelwit om die effekte van EFE te definieer, hoe dit verteerbaarheid beïnvloed en die metode van werking daarvan te ondersoek. Vanuit die literatuur is dit duidelik dat daar wel baie positiewe effekte is waar ruvoere met EFE behandel is en dat diereproduksie wel bevoordeel word daardeur. Vanuit die studie is dit getoon dat die tempo en hoeveelheid gasproduksie van sekere ruvoere (lusern, kikuyu en oulandsgras) verbeter word deur EFE behandeling (P < 0.05). Hierdie bevinding was ondersteun deur verbeterde in vitro verteerbaarheid van die ruvoere (P < 0.05). Dit is in ooreenstemming met literatuur en die gevolgtrekking is gemaak dat hierdie effekte tydens die vroeëre stadia van vertering verwag kan word. ʼn Volledige skaapvoer wat met EFE behandel is, het positiewe effekte op in sacco verteerbaarheid en verterings kinetika data gehad (P < 0.05). Weereens is die in vitro verteerbaarheid van die voer verbeter (P < 0.05). Waarnemings op in vitro verteerbaarheid was veel minder opvallend wanneer ʼn gesuiwerde xylanase as enigste fibrolitiese ensiem behandeling gebruik is. Dit is dus duidelik dat ensiem spesifisiteit ʼn belangrike rol speel in die verkryging van positiewe resultate in die verteerbaarheid van ruvoere en veevoere. In ooreenstemming met literatuur word dit voorgestel dat ensiemmengsels wat verskeie ensieme bevat as EFE gebruik behoort te word ten einde aan die kompleksiteit van die substraat te voldoen. Die hoof doelwit van die studie was egter ʼn indiepte ondersoek na die metode van werking van EFE. Hierdie doelwit is benader deur die effekte van EFE op selwand strukture van plantmateriaal op ʼn histologiese vlak te ondersoek. Die ruvoere was vooraf met EFE behandel en in vitro geïnkubeer in rumen vloeistof. Die resultate het getoon dat EFE ʼn matige, dog betekenisvolle effek op die selwand materiaal van die onderskeie weefsels gehad het (P < 0.05). Die belangrikste waargeneemde effek was dat EFE ʼn verdunningseffek op die selwande gehad het. Dit is afgelei dat as EFE die selwand kan beïnvloed, mikro-organismes vroeër toegang tot die inhoud kan kry. Verder, nutriënte vasgevang in die selwand matriks raak ook beskikbaar vir vertering. Hierdie afleiding en die effek van EFE op selwande verklaar waarnemings dat EFE die tempo van vertering sowel as die vlak van vertering van nie net vesel, maar ook proteïen kan bevoordeel. Die gevolgtrekking is gemaak dat daar definitiewe meriete is in die gebruik van EFE om die verteerbaarheid van herkouervoere te verbeter en dat dit verband hou met die ensiem se werking op selwande van die ruvoere. Die effekte kan verwag word tydens die vroeë stadia van vertering om dus deurvloeitempo van digesta te verbeter. Die effek van die EFE is verder nie beperk tot vesel nie, maar positiewe effekte op ander nutriënte kan verwag word en vervolgens ʼn algehele verhoging in die verteerbaarheid van die voer. Navorsing behoort in die toekoms verder die metode van werking van EFE te ondersoek deur gebruik te maak van gevorderde tegnologie wat alledaags gebruik word in die Plantwetenskappe. Die belowendste aanwending van EFE lê in die verbetering in vertering van swak kwaliteit ruvoere. Dit is ongelukkig juis hier waar min positiewe resultate gerapporteer word en indiepte navorsing moet onderneem word om ensiem spesifisiteit en optimum kondisies te definieer sodat EFE beter opgewasse is teen die kompleksiteit van die substraat.

The influence of feeding juvenile female leopard tortoises (Geochelone pardalis, n=18) a commercially available, complete, extruded feed three (3) or seven days (7) per week on dry matter and digestible energy intake, apparent digestibility of dry matter, organic matter, gross energy and fiber fractions, animal body weight and measurements, digesta transit time, rate of passage, and indigestible fill was evaluated. Both feeding frequencies are commonly practiced with captive tortoises. When fed 7 compared to 3 days per week, dry matter and digestible energy intake was greater. Tortoises gained more g BW, but not when adjusted per kg initial BW. When fed 7 compared to 3 days per week, tortoises grew more in plastron width (PW) and carapace height (CH), but not midline straight carapace length (MSCL), and grew more in calculated shell volume (i.e., a calculated estimate of shell volume using MSCL, PW, and CH), with a higher calculated body condition index (BCI). Providing short fasts (i.e., feeding 3 compared to 7 days per week) may be useful in slowing tortoise growth when animals are provided food ad libitum. In general, ad libitum feeding, especially of a highly digestible extruded feed, is not recommended for captive juvenile G. pardalis, especially when offered food daily. With two data points (detected as outliers) removed due to low fecal output (and resulting unrealistically high apparent digestibility of all nutrients analyzed) of two animals when fed 3 days per week, apparent digestibility of cellulose in tortoises fed 7 (n=18) compared to 3 (n=16) days per week was lower, but no differences were detected in DM, OM, GE, or any other fiber fractions analyzed. Transit time (TT1) was shorter and indigestible fill was higher in tortoises (n=18) fed 7 compared to 3 days per week, regardless of percent Cr marker recovered. With four animals removed due to <50% Cr marker recovery, tortoises fed 7 compared to 3 days per week exhibited shorter mean retention time (RGIT), with no differences in digesta transit or indigestible fill. Longer digesta retention when food availability included short periods of fasting may have allowed tortoises to extract more energy from cellulose.

Thesis (M.S.)--East Tennessee State University, 2004.
Title from electronic submission form. ETSU ETD database URN: etd-0309104-192944. Includes bibliographical references. Also available via Internet at the UMI web site.

Thesis (MSc Food Sc)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: The aim of this study was to determine the proximate composition of five individual body sites of the Mustelus mustelus shark in order to evaluate the cross carcass variation of the individual proximate components (moisture, protein, lipid, ash) of the meat. This variation was determined in order to find a representative sample of the edible part of the shark (fillet and body flap). Secondly, this sample representing the entire shark fillet was used to investigate the endogenous factors (gender, size and life cycle stage) and their effects on the individual proximate components and other meat components (amino acids, fatty acids, minerals, histamine and mercury contents). Finally, all this data was combined to describe the average chemical composition and nutritional value of M. mustelus meat. None of the proximate components showed any variation between the different fillet positions. This indicated that the fillet is homogenous and samples for chemical analyses can be taken anywhere on the fillet as representative of the entire fillet. It was found that all three main effects (gender, size and life cycle stage) did not have major influences on most of the components of the chemical composition of M. mustelus meat analysed. Higher fatty acid levels (SFA, MUFA and PUFA) were observed in large females than in large males as well as in non-pregnant large females compared to pregnant large females. According to statistical analysis, large males had higher total mercury levels than large females. The only component affected by size variation was the fatty acids, showing a trend to decrease in quantity before maturity was reached. Variation due to life cycle stages was mostly evident in the fatty acid component with some small effects on two mineral components, aluminium and copper, which had slightly higher levels in pregnant large females than in non-pregnant large females. M. mustelus meat has an average proximate composition of 75% moisture, 23% protein, 1.6% lipids and 1.4% ash (weight per wet weight). The protein is, however, an over-estimation of the true protein value as the meat contains significant amounts of non-protein nitrogen (NPN) in the form of urea which contributes to the N concentration. M. mustelus meat is a good source of some essential amino acids, especially lysine and threonine (78% of the daily requirements for an adult in a 100g portion), but low in minerals. The meat has a healthy lipid content with a good ratio (>0.45) of PUFA:SFA (0.83) as well as a healthy (<4) n-6:n-3 fatty acid ratio of 0.39. The histamine content was very low or not detectable but some samples contained total mercury values above the maximum safe limit. Although further research is needed for some meat components, these results are a valuable contribution to the new South African Food Composition Tables being compiled.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die proksimale samestelling van die vleis vanaf vyf afsonderlike posisies op die liggaam van die Mustelus mustelus haai te bepaal. Sodoende is die variasie, met betrekking tot die verskillende proksimale komponente (vog, proteïen, lipiede en as), in terme van die totale karkas, bepaal. Die proksimale variasie is bepaal om vas te stel hoe ʼn verteenwoordigende monster van die totale karkas geneem kan word. Gevolglik is hierdie verteenwoordigende monster gebruik om die effek van geslag, grootte en die verskillende fases van die lewens-siklus op die afsonderlike proksimale komponente asook ander vleis komponente (aminosure, vetsure, minerale, histamien en kwik inhoud) te ondersoek. Laastens is al hierdie inligting gebruik om die algemene samestelling en voedingswaarde van M. mustelus vleis te bespreek. Geen van die proksimale komponente het enige variasie getoon tussen afsonderlike liggaamsposisies nie. Hierdie resultaat dui daarop dat die vleis van ʼn M. mustelus haai homogeen is regoor die karkas en dat ʼn vleis monster vanaf enige posisie op die karkas geneem kan word as ʼn verteenwoordigende monster. Daar is gevind dat geslag, grootte en fase van die lewens-siklus geen merkwaardige invloed het op die vleis se samestelling nie. Hoër vetsuur konsentrasies (versadigde, monoonversadigde en poli-onversadigde vetsure) is gevind in groot vroulike haaie en nie-dragtige vroulike haaie as in groot manlike haaie en dragtige vroulike haaie onderskeidelik. Statisties, het groot manlike haaie hoër vlakke van totale kwik as groot vroulike haaie. Die enigste vleis komponent wat beïnvloed is deur die grootte van die haai, is die vetsure, wat verminder het voor volwassenheid bereik is en dan weer vermeerder soos die haai groter word. Variasie as gevolg van die verskillende fases van die lewens-siklus is meestal gevind in die vetsuursamestelling, en die minimale het ook gevarieer ten opsigte van die elemente aluminium en boor wat effense hoër vlakke getoon het in dragtige haaie as in nie-dragtige haaie. M. mustelus vleis het ʼn gemiddelde proksimale samestelling van 75% vog, 23% proteïen, 1.6% lipiede en 1.4% as (nat massa). Die proteïen waarde is ʼn oorskatting van die ware proteïen waarde as gevolg van hoë nie-proteïen stikstof in die vorm van ureum wat bydra tot die totale stikstof inhoud. M. mustelus vleis blyk ʼn goeie bron van sommige essensiële aminosure soos lisien en treonien (78% van die daaglikse aanbevole dosis), maar laag in mineraal inhoud. Die vleis het ʼn gesonde vet inhoud met ʼn goeie (>0.045) poli-onversadigde:versadigde vetsuur verhouding (0.83) asook ʼn gesonde (<4) omega 6 tot omega 3 vetsuur verhouding van 0.39. Die histamien inhoud van die vleis was baie laag of onder die meetbare limiet, maar sekere monsters het ʼn totale kwik inhoud getoon wat bo die maksimum veilige limiet is. Hoewel verdere navorsing ten opsigte van sekere van die vleis komponente vereis word, lewer hierdie resultate ʼn waardevolle bydrae tot die nuwe Suid-Afrikaanse voedsel samestellings tabelle wat tans opgestel word.

Poultry-related salmonellosis is an on-going problem that the poultry industry must continue to address. To address these challenges, Salmonella populations present on litter and fecal samples of brooder and grow-out turkey farms were assessed using a quantitative procedure. Furthermore, serotyping, genotyping by pulsed-field gel electrophoresis and antibiotic resistance-susceptibility analyses were used to investigate the diversity of the Salmonella serotypes present on these farms. Additionally, alternative on-farm pathogen intervention strategies including feeding whole or coarsely ground grains, increasing insoluble fiber content of the diet and use of an alternative non-litter cage-based housing design (Broilermatic System) were evaluated. Salmonella litter populations averaged 2 logs higher in 3-wk turkey samples compared to samples from 19-wk birds. Turkey age also influenced Salmonella serotypes, genotypes and antibiotic resistance profiles. Only serovars Javiana and Mbandaka were common between 3 and 19-wk old turkeys. A higher frequency of multidrug resistance was observed in Salmonella isolates recovered from samples of 3-wk birds, on average isolates were resistant to >4 antibiotics tested. Supplementing coarse ground corn and increased insoluble fiber (wood fiber) content into the turkey diet did not adversely impact body weights. However, the treatments did not influence Salmonella colonization or fecal shedding of turkeys. To examine the impact of housing design and addition of whole or coarsely ground grains on performance, intestinal microbial diversity and Salmonella colonization, broilers were reared on four diets consisting of finely or coarsely ground corn and finely ground or whole triticale to market age and Salmonella populations measured. Whole grain supplementation decreased Salmonella cecal populations while rearing broilers on litter floor as opposed to the Broilermatic System resulted in significant reductions in Salmonella cecal populations. Moreover, feeding whole triticale presumably encouraged the proliferation of bacterial populations which may have competitively excluded Salmonella in the ceca of broilers. In conclusion, highly variable Salmonella populations and serotypes were detected across all commercial turkey farms and the use of alternative feed ingredients such as triticale may help to reduce Salmonella colonization in poultry. Moreover, diet composition and grain coarseness as well as housing design can influence the diversity of the commensal intestinal microflora which may help in the control of Salmonella colonization in broiler intestines.

Estimating nutrient and energy requirements of exotic animals is a necessary component of nutrition management in zoos and other wildlife facilities. In the absence of species-specific data, domestic animal models are often referenced. Herbivorous hindgut fermenters, such as horses, zebra, and rhinoceros, rely on microbial fermentation in the cecum and colon to utilize dietary structural carbohydrates. The study objective was to measure the digestible energy of two (LOW, HIGH) complete pelleted diets by the horse as a model for nondomestic hindgut fermenters. Seven, individually housed, adult Quarter Horse (Equus caballus) geldings were assigned to one of two diets as 100% of intake in a randomized crossover design. Experimental diets both contained similar ingredients including soybean oil as an added source of supplemental fat (LOW 1.7%, HIGH 6.9%). Diets differed in predicted digestible energy (LOW 2.29 Mcal/kg, HIGH 2.85 Mcal/kg, DE), ether extract (LOW 4.00%, HIGH 7.41%, EE), and acid detergent fiber (LOW 33.7%, HIGH 26.2%, ADF). Daily feed quantities were offered at 33.3 kcal DE BWkg-1 equally distributed over three meals to maintain target BW. Daily feed intake was quantified. Horses had ab libitum access to water. Horses were transitioned from all forage to 100% test diet over 14 d, acclimated to the test feed for 19 d prior to 4 d acclimation and 6 d total fecal collection using hygiene collection harnesses (Equi-San Marketing Pty Ltd). Diet transition between periods occurred over 8 d. Total fecal output was quantified every 8 h, thoroughly mixed and 10% of measured mass output was subsampled for further analysis. Body weights (BW) recorded weekly did not change significantly throughout the trial (P = 0.420). Apparent digestibility of diet within horse and day was evaluated by a nested ANOVA (Minitab 16). The apparent digestibility of EE (P < 0.000), neutral detergent fiber (P = 0.008), and ADF (P = 0.002) differed between the two diets. Apparent digestibility of DM (P = 0.137), OM (P = 0.140), and GE (P = 0.418) were not different. Excess fat not digested and absorbed in the small intestine (by-pass fat) will enter the hindgut and may cause disruption of normal microbial activity. Additionally soybean oil, when consumed in quantities that allow by-pass to occur, has been shown to have a negative effect on fiber digestibility in hindgut fermenters. A negative effect on fiber digestibility in the higher fat diet could result in diets closer in DM, OM, and GE digestibility than initially predicted. The NRC (2007) recommends that no more than 0.7 g/kg BW/d of soybean oil be fed to the horse. The HIGH diet provided 0.91 g/kg BW/d soybean oil. Feeds that contain concentrations higher than recommended may not be appropriate as the sole dietary ingredient of hindgut fermenters. Further studies are needed to evaluate the use of soybean oil and to determine the threshold at which soybean oil will begin to suppress hindgut fiber digestion. In vivo measurements of digestibility in model species may provide useful benchmarks from which diets for nondomestic hindgut fermenters, as well as horses, may be formulated.

Background: College students experience food insecurity at a rate 3.5 times higher than the U.S. general population, affecting 43% of students. Furthermore, college students consume high amounts of ultra-processed products. NOVA, a food classification system, takes into account food processing and is thought to better fit the modern food environment. Purpose: The purpose of this research project was to examine the impact of CalFresh enrollment on food security status. This study also evaluated the impact of two different nutrition education interventions (MyPlate and MyPlate+NOVA) on participants’ dietary habits and nutrition knowledge. Methods: Food security, dietary habits, and nutrition knowledge were assessed at baseline, three-month, and at six months follow-up. Food security status was measured using the USDA 6-item Short Form Food Security Assessment Module. A 12-week mobile nutrition education intervention providing MyPlate or MyPlate+NOVA nutrition messages was implemented, and dietary habits were assessed using an adapted NHANES 2009-2010 dietary screener questionnaire, while nutrition knowledge questions were created from the nutrition education messages. Results: Food insecurity decreased by approximately 63% among CalFresh participants. There were no differences in dietary habits or nutrition knowledge among any of the intervention groups or the control group.

This experiment evaluated rumen protein:energy synchronization in steers fed either gamagrass (Tripsacum dactyloides) or orchardgrass (Dactylis glomerata) hays with or without a soybean hull/corn supplement. A N balance trial was conducted to compare the effects of the supplement and hay on N intake, N digestion, and N metabolism. The supplement consisted of 50:50 corn: soybean hulls mix with 50 g molasses per kg of corn: soybean hulls mixture. The supplement contained 11.3% CP, 34.2% NDF, 22.9% ADF, and 0.87 kg was fed at 0830 and 1600 followed by hay offered in two equal portions. Steers had ad libitum access to water and a trace mineralized salt block throughout the study. Hay compositions were 8.3% CP, 71.8% NDF, and 37.8% ADF for gamagrass and were 11.9% CP, 70.5% NDF, and 36.6% ADF for orchardgrass. Steers were individually fed, blocked into two weight groups, and randomly assigned to either gamagrass or orchardgrass hay (4 steers per hay). Within hays, steers were assigned to receive supplement or no supplement in a crossover design. Ad libitum DM intake for each steer was equal to their intake during the last 8d of the 21-d ad libitum period. Steers were then placed in metabolism crates for an 8-d adjustment followed by a 5-d balance trial. During the balance trial, steers were fed 90% of ad libitum intake. Compared with gamagrass, orchardgrass had similar true IVDMD (64.2 vs 62.2%), similar leaf true IVDMD (58.2 vs 63.2%), and similar stem true IVDMD (46.7 vs 51.7%). Effects were significant at P < 0.10. Compared with gamagrass, orchardgrass had a lower ad libitum DM intake (4.62 vs 5.37 kg/d), higher N intake (96.6 vs 81.1 g/d), similar fecal N (36.1 vs 34.5 g/d), higher N digestibility (62.4 vs 57.4 %), similar N retained (27.2 vs 27.7 g/d), and lower digestible DMI (3.20 vs 3.53 kg/d). Compared with no supplement, supplement increased digestible DM intake (3.70 vs 3.03 kg/d), total DM intake (5.87 vs 5.07 kg/d), N intake (96.9 vs 80.8 g/d), fecal N (39.4 vs 31.1 g/d) and N retained (31.7 vs 23.2 g/d). Supplement (1.74 kg/d) decreased hay ad libitum intake by 0.73 kg/d. Supplement decreased, blood urea N, urine urea N and urine urea N as a percentage of urine N more for orchardgrass than for gamagrass. Supplement tended (P < 0.11) to improve N retained as a percentage of N intake or percentage of N digested more for orchardgrass than for gamagrass hay. Blood urea N was reduced (2.21 vs 0.14 mM)more for steers fed orchardgrass hay than for steers fed gamagrass. We believe that the increase in digestible OM intake is due in part to the presence of soybean hulls in the supplement.

Thesis (PhD(Agric) (Animal Sciences))--University of Stellenbosch, 2006.
This project consisted of five studies. The objectives were to determine the essential amino acid (AA) requirements of growing woolled lambs (Merino and Dohne Merino) and the essential AA profile of duodenal digesta pre-dominantly derived from microbial protein. The limiting essential AA`s in high rumen degradable protein (RDP) diets to growing lambs, where microbial protein is the primary source of AA`s, were also identified. The first study determined the essential AA profile of duodenal protein on a high rumen degradable diet and evaluated the impact of dietary RDP concentration and source [true RDP vs. non-protein nitrogen (NPN)] on the AA composition of supplied in the duodenum. The first trial in this study evaluated the effects of increasing true RDP levels on the essential AA composition of duodenal protein primarily derived from rumen microbes. The lambs had free access to wheat straw and fresh water. The daily RDP supplements were administered in two equal doses into the rumens through rumen cannulas at 07:00 and 19:00. Duodenal digesta was extracted with 6h intervals through T-type cannulas, inserted proximally to the common bile duct. Sampling time was advanced 2h every day to obtain duodenal samples on every even hour of a 24h period after three days. As expected, deficient RDP limited the supply of essential AA`s in the iv duodenum. When the true RDP supplements increased, the duodenal flow of essential AA`s also increased concomitantly, but appeared to level off at the higher RDP levels. Despite the positive quantitative effects of true RDP supplementation on AA supply to the duodenum, the AA profile in the duodenum was unaltered. Consequently, the essential AA profile of duodenal protein of sheep receiving high RDP diets, where microbial protein is the primary source of AA`s in the duodenum, is relatively constant and insensitive to dietary RDP concentration. In the second trial the effects of RDP source (true RDP vs. NPN) on the essential AA profile of duodenal protein on high RDP diets were evaluated by substituting increasing amounts of urea for true RDP in isonitrogenous teatments. Higher NPN increments reduced the daily supply of essential AA`s in the duodenum. In corroboration of the first trial, the AA profile of the duodenal protein was very constant, irrespective of the RDP source. Since microbial protein is the major source of duodenal AA`s on high RDP diets, this study supports the view that microbial protein has a relatively constant AA profile, but microbial protein yield varies according to several rate limiting factors in the rumen. A constant microbial AA profile allows accurate estimates of microbial essential AA supply in the small intestine if microbial protein production and fluid and particulate outflow rates from the rumen can be accurately predicted. This allows the development of more accurate undegradable protein (UDP) supplementation strategies, based on the essential AA requirements of animals. In the second study growing male Merino and Dohne Merino lambs were slaughtered at different weights and body condition scores. The digesta was removed from the stomachs and intestines and every organ or body part were weighed to determine the whole empty body (WEB) composition. The WEB was partitioned into the carcass, internall offal (stomachs, intestines, organs and blood) and external offal (head, feet, skin and wool). No differences were apparent in the proportional weight distribution of similar body components of the same breed at different ages. In a comparison between breeds, the proportional weight contributions of the carcasses from both breeds to the WEB weight were remarkably similar at both slaughtering stages. The Dohne Merino lambs had proportionally larger internal offals and smaller external offals than the Merino lambs at both slaughters. Unless the essential amino acid compositions of the internal and external offals were identical to the carcass, the dissimilarities in weight and protein allocation to these two components within the WEB`s of Merino and Dohne Merino lambs imply a distinct WEB essential AA composition for each breed. The apparent digestibilities of dry matter (DM), crude protein (CP), energy, acid detergent fibre (ADF), neutral detergent fibre (NDF), fat and ash did not differ between Merino and Dohne Merino lambs. Energy retention was also similar for the two breeds, but the Merino lambs retained considerably more N than the Dohne Merino lambs. This may also impact on the respective amino acid requirements of the lambs. Since the Merino lambs utilise N more efficiently, they may have potentially lower essential amino acid requirements to achieve a similar growth rate. The WEB essential AA compositions of growing Merino and Dohne Merino lambs were determined in the third study. Based on the ideal protein concept, the WEB essential AA profile was accepted as representative of the AA requirements for growth. The use of a single body part as a representation of the WEB AA profile was also evaluated. Differences in the proportional weight and protein contribution of the three body components (carcass, internal offal and external offal) of the two breeds strongly suggested that the WEB AA composition of the breeds would differ, because of likely differences in the AA profiles of these components. The essential AA profiles of the carcasses from the two breeds were surprisingly similar. However, the essential AA compositions of the internal offal and external offal differed substantially from each other, as well as from the carcass. In addition, the internal offal and external offals of each breed had characteristic essential AA profiles. Inevitably, the WEB essential AA profiles of Merino and Dohne Merino lambs differed considerably. Only the leucine and phenylalanine concentrations in the WEB`s of Merino and Dohne Merino lambs did not differ. Significant differences in the concentrations of eight essential AA`s implied that the two breeds have different AA requirements for growth. The different AA compositions of the internal and external offal within each breed also illustrated that the use of a single body component, like the carcass, as a predictor of WEB essential AA composition contains considerable inaccuracies. The essential AA index indicated that the duodenal protein, primarily derived from rumen microbes, provided approximately 81 % of the qualitative AA requirements of growing lambs. During periods of sufficient availability of very low-quality forage, as the diet in this study simulated, microbial protein is not able to support maximum growth. The first two limiting AA`s (histidine and methionine) could not even support daily growth rates of 100 g/d. This is very low and stresses the need for effective undegradable AA supplementation under these conditions. Chemical scores identified histidine as the first limiting AA in high RDP diets (predominantly microbial protein), followed by methionine, leucine, arginine and phenylalanine. However, the requirements for histidine and arginine are frequently over estimated and these AA`s should actually be considered semi-essential, which could render methionine, leucine and phenylalanine the first three limiting AA`s to growing lambs receiving high RDP diets. Because of the limitations of static measurement systems for the determination of AA requirements, a more comprehensive evaluation method was introduced for determination of the limiting AA`s in duodenal protein of lambs on high RDP diets, in the fourth study. The fourth study focused on the identification of limiting AA`s to growing lambs being limit-fed a high RDP diet. The diet consisted primarily of soybean hulls, for its’ low rumen UDP content. Microbial protein production was calculated as 13 % of total digestible nutrient intake and complementary AA supplements prepared to simulate the WEB AA profile, determined in the previous study, in the small intestine. To eliminate the influence of the rumen on the AA supplements, the latter were infused into the abomasums via flexible tubing. Each essential AA was in turn removed from the control treatment (simulating the WEB composition) and the effect on N retention measured. When methionine or the branched-chain amino acids (BCAA`s) were removed from the infusate, N retention of the lambs was reduced. Consequently, methionine and at least one of the BCAA`s limited growth performance of young lambs when microbial protein was the predominant source of AA`s. The concomitant increased plasma concentrations of total AA`s when methionine or the BCAA`s were removed from the infusate corroborates the effects on N retention, since it indicates that AA utilisation was reduced when these AA imbalances were introduced. Amino acid imbalances had no effect on apparent DM, organic matter (OM) or NDF digestion, but N digestibility was reduced. The final study verified whether the BCAA’s were co-limiting the growth of lambs, or if any single BCAA was responsible for the limitation. Again the WEB AA profile of growing lambs was simulated in the small intestine via abomasal infusions to lambs receiving a soybean hull-based diet. Leucine, isoleucine and valine were individually or simultaneously removed from the infusate and the impact on N retention measured. On an individual basis valine had the largest negative impact on the efficiency of N utilisation. However, the simultaneous removal of the BCAA`s resulted in the lowest N retention, suggesting that valine might be limiting, but the three BCAA`s are more likely to be co-limiting in diets to growing lambs where microbial protein is the primary source of AA`s. Once again, neither DM, OM or NDF digestibility were affected by the AA imbalances. Nitrogen digestibility was, however, negatively affected by AA imbalances. This project succeeded in establishing the essential AA profile of duodenal protein in sheep receiving high RDP diets. The WEB essential AA compositions of growing lambs from two prominent sheep breeds in South Afica were then determined and the duodenal essential AA profile evaluated against the calculated AA requirements. Finally, the AA`s that limit growth in diets where microbial protein is the predominant source thereof were identified. These results contribute to the current knowledge of AA requirements in growing lambs, and highlight areas for future research, as discussed in the General Conclusion.

A healthy diet has been established as a key component contributing to an individual’s quality of life. Statistics show that the diet of Americans needs improvement (Guenther et al., 2007) indicating possible lack knowledge of what healthy eating behaviors are. There is an abundance of nutrition misinformation available to the consumer (American Dietetic Association, 2002a). Dietary interventions that provide credible education based on readiness to change behaviors and goal setting have been successful in increasing awareness of what healthy eating behaviors are and changing existing behaviors over time (Ammerman et al., 2002; Evans & Sawyer-Morse, 2002; Gambera et al., 1995; Hebert et al., 1999; Oenema & Brug, 2003; Proper, et al., 2003). In an effort to provide a college community with credible nutrition education based on dietary analysis and stage of change, a nutrition assessment and consultation program was developed and implemented at a college campus during the fall 2003 quarter. It was integrated into the existing fitness testing and prescription program, polyFIT. Seven students, referred to as fitness consultants, majoring in Nutrition or Kinesiology were recruited and trained to distribute appropriate education based on individual clients’ dietary analysis, a stage of change assessment and personal goals. Intervention materials were constructed using a variety of resources focusing on areas of nutrition. Thirty clients participated during the fall 2003 quarter; all were freshman and sophomores enrolled in a Healthy Living course. Separate survey questionnaires were designed for the consultants and the clients to gather their perceptions of the program components. PolyFIT continued to offer the program, modifying it over time, for at least 4 years after the initial implementation.

Thesis (MScAgric)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: The objective of this study was to determine the effect of extrusion, as a method of heat treatment, on the dry matter (DM) and crude protein (CP) degradability parameters of various vegetable protein sources commonly used in the Western Cape Province, South Africa. The feedstuffs used were lupins (LUP), full fat soybeans (SB), full fat canola seeds (FCS), soybean meal (SBM), canola meal (CM) and sunflower meal (SFM). In the first trial, the degradability parameters were determined according to an in sacco degradability procedure. Four non-lactating Holstein cows, fitted with rumen cannulae, were used in the trial and all cows received the same basal lactation diet. The samples were incubated in dacron bags and bags were removed at intervals of 0, 2, 4, 8, 16, 24 and 48 hours. Dry matter and CP disappearance values were determined and fitted to a onecompartment model by means of an iterative least-square procedure in order to determine the DM and CP degradability parameters. Results indicated that extrusion significantly lowered the effective degradability of the DM-fraction (20.1% on average) of all the feedstuffs, except LUP, and the effective degradability of CP in all the raw materials (27% on average). The second trial was an in vitro degradability trial that ran parallel with the in sacco degradability trial and was done with the aid of a DaisyII Incubator (ANKOM Technology Corp., Fairport, NY). The same feedstuffs were tested in both trials. A composited sample of rumen liquor from two of the cows used in the in sacco trial was used for in vitro incubation of the samples. The data obtained in this trial were analyzed in a similar way to that of the in sacco trial. Due to a limited amount of residue left after incubation, CP disappearance could not be calculated at each time interval for SB and SBM in the in vitro trial. In this case, actual disappearance values after 8h were used to compare treatments. Extrusion significantly lowered the effective degradability (as determined in vitro) of DM in all the feedstuffs tested (16.8% on average), as well as the effective degradability of CP in LUP, FCS, CM and SFM (21.8% on average). A comparison of the actual disappearance values after 8 hours incubation indicated that extrusion also lowered the rate of CP disappearance for SB and SBM. The values obtained in the in vitro trial and those from the in sacco trial, for the same feedstuffs, were compared. It appeared as if the in vitro determined values were overestimations of the in sacco determined values. A regression analysis showed a high correlation between the actual in vitro CP disappearance values after 8h incubation and in sacco determined effective degradability values. The third part of this study was a set of chemical analysis to determine the effect of extrusion on certain nitrogen fractions of the feedstuffs tested in the above mentioned trials. Solubility in a mineral buffer solution was determined to estimate the potential rumen degradability of the protein. The buffer insoluble nitrogen (BIN) fraction of all the feedstuffs, except FCS, was significantly increased by extrusion. Extrusion lowered the acid detergent insoluble nitrogen (ADIN) content of all feedstuffs, except FCS, which could imply that the temperature reached during extrusion (115°C - 120°C) was not high enough to cause damage to the protein. The neutral detergent insoluble nitrogen (NDIN) fraction of extruded SB, SBM, CM and SFM was significantly higher than that of the raw feedstuffs. Extrusion left the NDIN-fraction of FCS and LUP unaltered. Comparison of the NDIN : ADIN ratio of extruded with that of the raw feedstuffs provided reason to believe that extrusion had a positive effect on all feedstuffs (except FCS). Extrusion appears to be a useful method to decrease rumen degradation of vegetable protein sources, without causing heat damage. Furthermore, this means that protein sources of which the use have been limited due to its high rumen degradable protein (RDP) content, could be included in diets at higher levels following extrusion. The protein sources mentioned are also good sources of energy and the combination of energy and rumen undegradable protein (RUP) in the diet of the high-producing dairy cow could only be beneficial.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die effek van ekstrusie op die droëmateriaal (DM) en ruproteïen (RP)-degradeerbaarheidsparameters van verskeie plantaardige proteïenbronne wat algemeen in die Wes-Kaap (RSA), gebruik word, te bepaal. Ekstrusie is ‘n metode van hitteprosessering wat algemeen gebruik word deur plaaslike en internasionale veevoervervaardigers. Die volgende grondstowwe is geëvalueer: lupiene, volvet sojabone, volvet canolasaad, sojaboon-oliekoekmeel, canola-oliekoekmeel en sonneblom-oliekoekmeel. In die eerste proef is die degradeerbaarheidsparameters met behulp van ‘n in sacco studie bepaal. Vier droë Holstein koeie met rumen kannulas is in die studie gebruik en al vier koeie het dieselfde basale dieet ontvang. Monsters is in dacronsakkies geïnkubeer en die sakkies is uit die rumen verwyder na onderskeidelik 0, 2, 4, 8, 16, 24 en 48 uur intervalle. Die waardes van DM- en RP- verdwyning is bereken en dan met ‘n iteratiewe kleinste kwadraat prosedure op ‘n een-kompartement model gepas om die in sacco DM- en RPdegradeerbaarheidsparameters te bepaal. Die resultate van die studie het getoon dat ekstrusie die effektiewe degradeerbaarheid van die DM-fraksie van al die grondstowwe, behalwe lupiene, betekenisvol verlaag het (met gemiddeld 20.1%), asook die effektiewe degradeerbaarheid van die RP-fraksie van al die grondstowwe (met gemiddeld 27%). Die tweede proef was ‘n in vitro-degradeerbaarheidsstudie wat met behulp van ‘n ANKOM DaisyII Inkubeerder uitgevoer is en wat parallel met die in sacco-studie gedoen is. Dieselfde grondstowwe is in beide proewe geëvalueer. ‘n Saamgestelde monster van die rumenvloeistof van twee van die koeie wat vir die in sacco-studie gebruik is, is gebruik vir die in vitro-inkubasie van die monsters. Data-verwerking is op ‘n soortgelyke wyse as dié van die in sacco-studie uitgevoer. As gevolg van ‘n beperkte hoeveelheid residu na afloop van die inkubasies, kon die RP-verdwyning vir volvet sojabone en sojaboon oliekoekmeel nie bereken word nie. In hierdie geval is waargenome verdwyningswaardes na 8h gebruik om behandelings te vergelyk. Hierdie studie het getoon dat ekstrusie die effektiewe degradeerbaarheid van DM (soos in vitro bepaal) in al die getoetste grondstowwe betekenisvol verlaag het (met gemiddeld 16.8%). Die effektiewe degradeerbaarheid van RP in lupiene, volvet canola saad, canola oliekoekmeel en sonneblom oliekoekmeel is ook betekenisvol verlaag (met gemiddeld 21.8%). ‘n Vergelyking van die oorspronklike verdwyningswaardes van volvet sojabone en sojaboon oliekoekmeel na ‘n inkubasieperiode van 8 ure het ook getoon dat ekstrusie die tempo van RP-verdwyning uit die rumen vertraag het. Die in sacco- en in vitro-bepaalde waardes vir elke grondstof is vergelyk en dit kom voor asof die in vitro-waardes oorskattings van die in sacco-waardes is. ‘n Regressie-analise het verder getoon dat daar ‘n hoë korrelasie was tussen die waargenome in vitro RPverdwyningswaardes na 8 ure inkubasie en die beraamde effektiewe degradeerbaarheid, soos in sacco bepaal. Die derde deel van die studie was ‘n stel chemiese analises wat uitgevoer is om die effek van ekstrusie op sekere stikstof (N)-fraksies van die grondstowwe, wat in bogenoemde proewe gebruik is, te bepaal. Die oplosbaarheid van N in ‘n mineraal-bufferoplossing kan gebruik word as aanduiding van die potensiële rumendegradeerbaarheid van die proteïen. Die bufferonoplosbare N-fraksie van al die grondstowwe (behalwe volvet canolasaad) is betekenisvol verlaag deur ekstrusie. Ekstrusie het ook die suur-onoplosbare N-fraksie (ADIN) van al die grondstowwe (behalwe volvet canolasaad) betekenisvol verlaag. Dit kan moontlik daarop dui dat die temperatuur wat tydens ekstrusie (115°C - 120°C) bereik is, nie hoog genoeg was om die proteïen in die grondstowwe te beskadig nie. Ekstrusie het die N-fraksie wat onoplosbaar was in ‘n neutrale oplossing (NDIN) betekenisvol verhoog in volvet sojabone, sojaboonoliekoekmeel, canola-oliekoekmeel en sonneblom-oliekoekmeel en dit onveranderd gelaat in lupiene en volvet canolasaad). Die verhouding van NDIN : ADIN van die geëkstrueerde grondstowwe is vergelyk met dié van die rou grondstowwe. Dit blyk dat ekstrusie wel ‘n positiewe effek op al die grondstowwe (behalwe volvet canolasaad) gehad het. Dit wil dus voorkom asof ekstrusie wel aangewend kan word om die rumendegradeerbaarheid van plantaardige proteïenbronne te verlaag sonder om die protein te beskadig. Dit kan daartoe lei dat proteïenbronne waarvan die gebruik voorheen beperk was as gevolg van die hoë rumen-degradeerbare proteïen-inhoud daarvan nou wel in rantsoene ingesluit kan word na die ekstrusie daarvan. Die proteïenbronne, soos genoem, is ook redelike bronne van energie en die kombinasie van energie en rumen nie-degradeerbare proteïen in die rantsoen van die hoog-produserende melkkoei kan slegs voordelig wees.

Fruit split is the most important physiological disorder in pomegranate production, causing devastating crop losses worldwide. Foliar nutrient applications have been used experimentally to mitigate pomegranate fruit split but none have been conducted using the industry standard cultivar, Wonderful, and little is known about the effects of foliar nutrient applications on pomegranate. Additionally, investigations into putative health benefits of pomegranate fruit have increased interest in its production but limited evidence exists regarding effects of agricultural practices such as foliar fertilizer applications on internal fruit quality. ‘Wonderful’ pomegranate trees at 2 commercial orchards were treated with foliar applications of ZnSO4 (3000 mg∙L-1, 4000 mg∙L-1, or 5000 mg∙L-1), MgSO4 (1%, 2%, or 3%), KNO3 (1%, 2%, or 3%), or deionized (DI) water (control). Fruit were analyzed for fruit split incidence, yield, fruit number per tree, fruit diameter, fruit mass, mass of all arils in fruit, mass of 100 arils, total soluble solids (TSS), titratable acidity (TA), antioxidant activity (AA), total phenolics (TP), and mineral nutrient concentrations of leaves and fruit. Foliar applications of MgSO4 and ZnSO4 resulted in significantly lower fruit split incidence. Treatments had no significant effect on fruit number per tree, fruit diameter, and mass, mass of all arils in fruit, or mass of 100 arils. Leaf N, K, S, Mn, and Zn were significantly affected by the treatments. TSS and TA were not affected significantly by treatments. AA ranged from 77.8-84.3 percent inhibition of 2,2’-diphenyl-1-picrylhydrazyl and TP ranged from 2489-3046 mg·L-1 gallic acid equivalents, with some KNO3 treatments significantly affecting these parameters. Fruit mineral nutrient concentrations were characterized and Zn-treated trees had greater fruit Zn concentrations. The results suggest that foliar ZnSO4 or MgSO4 could be used to decrease fruit split incidence and increase nutritional content of ‘Wonderful’ pomegranate and any of the three tested foliar nutrients could be applied as a foliar fertilizer without negatively impacting fruit yield, size, internal quality, bioactivity, or mineral nutrient concentration.