<p>HASTY, JENNIFER. EFFECTS OF VITAMIN E SUPPLEMENTATION ON PORK QUALITY CHARACTERISTICS OF HAMPSHIRE CROSSES AND BERKSHIRE CROSSES. (Under the direction of Eric van Heugten). An experiment was conducted to investigate whether pork quality characteristics could be improved by feeding supra-nutritional levels of vitamin E (as a-tocopheryl acetate) to Berkshire x PIC and Hampshire x PIC finishing pigs. Diets contained 0, 75, 150, 300 or 600 mg a-tocopheryl acetate/kg and were fed ad libitum for six weeks. Pigs were biopsied on 0, 21 and 42 d to evaluate potential pork quality. After the six-week feeding period, pigs were humanely slaughtered at a commercial facility and the right loin was taken from previously biopsied pigs for pork quality measurements. Chops were packaged and placed in refrigerated illuminated conditions and displayed for 0, 2, 4, 6 and 8 d. Loin sections were vacuum packaged, refrigerated and stored for 25, 35, 45 and 55 d. Supplemental vitamin E had no effect on improving average daily gain and tended to increase average daily feed intake. Average daily gain and gain:feed were greater for the Hampshire crosses and average daily feed intake was greater for the Berkshire crosses over the six-week feeding period. Supplemental vitamin E had no effect on carcass characteristics but there were differences between the two genotypes with Berkshire crosses having greater back fat and a lower percent yield, loin eye area, and lean percent. Supplemental vitamin E had no effect on biopsy fluid loss or pH. Hampshire crosses had greater fluid loss measured on day 42 than Berkshire crosses. There was no effect of supplemental vitamin E on initial (taken 45 min after slaughter) or ultimate (taken 24 hrs after slaughter) pH or temperature of the carcasses. There were no differences between genotype for initial pH and initial or ultimate temperature; however, ultimate pH was greater for Berkshire crosses. Serum and tissue vitamin E levels both increased with increasing levels of vitamin E in the diet and tissue vitamin E levels were greater for Hampshire crosses. Drip loss taken 24 hrs after slaughter was not affected by supplemental vitamin E and was lower in Berkshire crosses. However, there was a tendency for increasing level of vitamin E to decrease drip loss for the display chops of Hampshire crosses. Drip loss for the vacuum packaged loin sections was not affected by supplemental vitamin E and was lower in Berkshire crosses. Minolta L* values, taken 24 hours after slaughter, were not influenced by vitamin E. There was a trend for increasing levels of vitamin E to linearly increase a* and b* values. Hampshire crosses had greater a* values than Berkshire crosses, indicating redder meat. Supplemental vitamin E had no effect on any of the Minolta color values for the display chops or chops from the vacuum packaged loin sections. Berkshire crosses had lower L* and b* values and Hampshire crosses had greater a* values for both the display chops and chops from the vacuum packaged loin sections. TBARS values measured for samples collected 24 hrs after slaughter were not affected by supplementation of vitamin E but were greater for Hampshire crosses. TBARS values for Hampshire crosses were consistently greater over the display period. For day 4, 6, and 8, TBARS values decreased with increasing levels of vitamin E in the diet. No differences were seen in 0 or 2 d samples. TBARS values for Hampshire crosses decreased linearly with increasing levels of vitamin E in the diet but no effects were seen for Berkshire crosses. TBARS for chops from vacuum packaged loin sections were not affected by supplemental vitamin E and did not differ between genotype.<P>

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

<p>PALA, AKIN. Effects of Three Twice-a-Year Breeding Schedules in Four Breeds of Sheep. (Under the direction of ODIS WAYNE ROBISON and ROGER LEE McCRAW).Straightbred populations of Dorset, Finnsheep, Composite I (50% Finnsheep, 25% Dorset, and 25% Rambouillet), and Composite II (50% Finnsheep, 25% Suffolk, and 25% Targhee) sheep were evaluated under three different twice-a-year breeding schedules. Ewes were exposed for 32 d starting on August 13 and February 5 for schedule I, on September 15 and March 10 for schedule II, and on October 22 and April 11 for schedule III. Approximately 100 ewes of each breed were exposed to rams during each breeding season. The experiment was conducted for five complete cycles starting with matings in the fall of 1984 and ending with matings in the spring of 1989. Data were obtained on 9419 lambs produced from 2334 ewes and 257 rams. Traits of primary interest were conception rate, litter size at birth, weaning weight, weaning weight adjusted for conception rate, litter weaning weight and litter weaning weight per ewe exposed. Lactation status had a significant effect on conception rate and litter size while number of lambs suckling did not have a significant effect on conception rate. Composite I ewes had the highest conception rates and litter size (P 0.10), both had larger litters (P < 0.01) than the other two breeds. Ewes giving birth in spring had the highest conception rate and heaviest lambs (P < 0.01). Animals bred in schedule I had the heaviest and largest litters, highest conception rate, heaviest lambs and highest litter weaning weight per ewe exposed (P < 0.01). Efficiency of twice-a-year lambing systems is greatly affected by breeds, breeding schedules and seasons. Twice-a-year lambing programs must use the correct breeding schedule. Further, using composite breeds can be of great benefit.Genetic parameters for conception rate, litter size at birth, weaning weight, weaning weight adjusted for conception rate, litter weaning weight and litter weaning weight per ewe exposed were estimated using REML with animal models. Heritability estimates for conception rate were adjusted to a normal scale. Standard errors of heritabilities for conception rate were calculated using three methods, including bootstrapping. Heritabilities were estimated overall and within breed. Estimates of heritability for conception rate ranged from 0.17 &#177 0.01 (Dorset) to 0.27 &#177 0.01 (Composite I). Heritability estimates for litter size were 0.08 &#177 0.01, 0.19 &#177 0.01, 0.14 &#177 0.01 and 0.13 &#177 0.01 for Dorset, Finnsheep, Composite I and Composite II, respectively. Heritabilities for litter weaning weight and litter weaning weight per ewe exposed were similar across breeds and ranged from 0.31 &#177 0.01 to 0.36 &#177 0.01. Heritability for weaning weight was higher for Dorset (0.65 &#177 0.01) than for Composite I (0.57 &#177 0.01). Finnsheep and Composite II had similar heritabilities (0.41 &#177 0.01). Overall heritabilities for litter weaning weight, litter weaning weight per ewe exposed, weaning weight, weaning weight adjusted for conception rate, conception rate and litter size were 0.33 &#177 0.02, 0.35 &#177 0.01, 0.64 &#177 0.01, 0.64 &#177 0.01, 0.24 &#177 0.01 and 0.16 &#177 0.01, respectively. Overall Spearman rank-order correlations of litter weight traits with conception rate or litter size ranged from 0.81 to 0.88. Correlations within breed were generally high and positive. Genetic correlations between dry and lactating ewes for conception rate and litter size were small (0.009 and 0.108, respectively), indicating that rank of sires was inconsistent under different environments (lactation status). Selection should be practiced among lactating animals for conception rate and litter size in twice-a-year lambing systems.Heritability estimates were moderate to high for weight traits and low to moderate for reproduction traits, indicating that selection in twice-a-year lambing programs is feasible. There was no substantial evidence that heritabilities and rank correlations were different among the four breeds. Litter weaning weight may be increased along with conception rate and litter size in a selection program based on twice-a-year lambing. Small genetic correlation between dry and lactating ewes indicated that grouping sires according to the lactation status of the ewes is necessary in a selection program.<P>

Introduction: The Tennessee Valley Authority is vitally interested in the effect of phosphorous on crop yields and the nutritional value of these crops on livestock. They manufacture different phosphatic fertilizers and test them on farms and in laboratories. Financial assistance is given by the Tennessee Valley Authority to the Tennessee Experiment Station in this study of the feeding value of clover hays of varying phosphorous contents for growing beef calves. This experiment was originated to (1) study growth of calves fed rations differing only in the phosphorous content of the red clover hay; and (2) to study the availability to growing beef calves of the phosphorous in the red clover hays having a different phosphorous content.

The honeybees Apis cerana and Apis mellifera are derived from the same ancestral base about two million years ago. With speciation and evolution, they have acquired many advanced living skills in common, but have also evolved very different living strategies due to different distributions. This thesis is an intensive study of the biology of the mixed-species colonies of these species, the aims of which were to investigate their behavioural relationships and uncover the evolutionary conserved features of their behaviours subsequent to speciation. The results show that the two species can form a stable society to perform normal tasks. First, workers of both species in the mixed-colonies could form the typical retinue behaviour to hetero-species queens, thus indicating that queen pheromones could be spread to and by both species. Secondly, both species did not show significantly different ovarian activation under hetero-species queens, suggesting that the queen pheromones more likely play a role of ―honest signal‖ rather than a ―repression‖ substance in the honeybee colonies. Thirdly, both species could mutually decode each other‘s waggle dances, with unexpectedly low misunderstanding; revealing that the dance language in a dark environment is quite adaptive for cavity-nesting honeybees. Fourthly, workers of both species could cooperate with each other in comb construction, although the combs they built contain many irregular cells. Interestingly, A. cerana workers could be stimulated by A. mellifera workers to perform this task, thus confirming self-organization theory in the colony. Fifthly, A. mellifera workers behaved more ―defectively‖ in thermoregulation, but perhaps because A. cerana workers are more sensitive to changes in hive temperature. Given these differences in strategy, A. mellifera workers‘ performance might in fact reduce conflicts. Lastly, when faced with threats of predatory wasps, both species engaged in aggressive defence. Although they did not learn from each other‘s responses, species-specific strategies were adopted by each of them so that the defence of the mixed-colonies is very effective. I conclude that the two species can adapt to each other‘s efforts and task allocation is reasonably organized allowing mixed-species colonies to reach stability. These results suggest that all of the social behaviours discussed here were highly conserved following speciation. This thesis could provide some clues for the study of honeybee evolution from open-nesting to the transition of cavity-nesting.

Studies were conducted to investigate the prevalence and potential for transfer of class 1 integrons and antimicrobial resistance in bacteria of broiler chickens and swine from the US and Thailand. Antibiograms were characterized and integron sequences were detected using standard methods. To determine if transfer of integrons occurred between bacterial species the location of the integrons (plasmid versus chromosome) was determined, and when integron-positive E. coli and Salmonella isolates possessed identical amplicon patterns, PCR products were sequenced to determine homology. Class 1 integrons were detected in 1,732 of 3,824 isolates from broiler chickens and 1,782 of 4,253 isolates from swine. Simultaneous presence of three conserved class 1 integron genes was found in 1,044 and 215 of isolates from chickens and swine, respectively. A high proportion of bacterial isolates from chickens demonstrated resistance to tetracycline, sulfamethoxazole, cephalothin, and ampicillin. A high proportion of isolates from swine demonstrated resistance to tetracycline, sulfamethoxazole, streptomycin, and ampicillin. Nine integron amplicons, with sizes ranging from 0.5 to 2.5 kb, were found, and we discovered a single swine farm on which similar integrons were observed in both E. coli and Salmonella. Sequence analysis revealed that a 1.0 kb amplicon found in both bacterial species contained an aadA1 gene cassette encoding aminoglycosides 3’-adenyltransferase, confering resistance to streptomycin and spectinomycin. A 2.0 kb amplicon was also found in both types of bacteria containing the aadA5 gene encoding aminoglycosides 3’-adenyltransferase, an additional reading frame with unknown function, orfD, as well as a dfrA17 gene encoding dihydrofolate reductase, conferring resistance to trimethoprim. Our results indicate that class 1 integrons are common in commensal and foodborne bacteria in broiler chickens and swine, and that some, but not all antibiotic resistances are associated with the presence of class 1 integrons. Identical integrons found in Salmonella and E. coli from a single farm likely indicate transfer between these two organisms occurs via exchange of plasmids. This work provides additional knowledge regarding the complex nature of antibiotic resistance gene acquisition, reservoirs, and transfer that should aid in development of courses of action and strategies for control of these potential foodborne and zoonotic hazards.

The overall aim of the studies described herein was to evaluate bovine spermatogonial cell dynamics under various conditions. Results from these experiments will provide the basis for potential production of offspring following spermatogonial stem cell transfer. Experiment 1 evaluated gonadotropin administration effects at initiation of inhibin passive immunization in Jersey bull calves on testicular morphology and development. Primary treatments consisted of control (KLH) or immunization (INH) plus a combination of saline, FSH, or GnRH. Administration of FSH at the time of initial immunization against inhibin significantly increased number of germ cells (92.2 ± 9 x 106 cells) compared to INH-Saline bulls (54.9 ± 10 x 106 cells) with INH-GnRH bulls being intermediate (64.5 ± 9 x 106 cells; P < 0.05). These results suggested that gonadotropin administration at time of inhibin immunization increases number of germ cells in the testis. Experiment 2 evaluated transiently induced ischemia in testes of Jersey calves on morphology and development. Treatments consisted of control or banding for 2 h, 4 h, and 8 h periods. Transiently induced ischemia significantly decreased number of germ cells in 8 h (12.6 ± 5 x 106 cells) compared to 0 (38.1 ± 6 x 106 cells), 2 (31.9 ± 6 x 106 cells), and 4 h (33.4 ± 5 x 106 cells; P < 0.05). These results suggested that transiently-induced ischemia significantly decreases number of germ, Sertoli and Leydig cells in the testis. Experiment 3 evaluated spermatogonial stem cells (SSC) proliferation, isolated from prepubertal and adult bulls, during short term in vitro culture. Spermatogonia were cultured in the presence or absence of a feeder monolayer (FL or NF), FBS type (FBS-S or FBS-SF), and media type (ELSC or RSC) treatment combinations. Viable type A spermatogonia survived under in vitro conditions and were able to proliferate and form different types of colonies. Furthermore, co-culture spermatogonial cells with a feeder monolayer plus FBS-S enhanced colony number (may be due to increasing cell viability). At 15 days of culture, colonies from both types of bulls were positive to AP. Therefore, these finding provide the basis for potential production of offspring through in vitro genetic manipulation such as intracytoplasmic sperm injection (ICSI), round spermatid injection (ROSI), or following SSC transfer.

Heat-induced reductions in developmental competence after direct exposure of oocytes to 41ºC have been coincident with reduced protein synthesis. Since heat stress perturbs RNA integrity and polyadenylation in somatic cells, it was hypothesized that heat stress during meiotic maturation may alter RNA within oocytes and/or their surrounding cumulus to account for some of the reductions in development. Initial efforts utilized microcapillary electrophoresis to examine oocyte and cumulus RNA without heat stress as a first step toward transcriptome profile analysis. Size distribution of RNA, rRNA ratio, and other related endpoints differed for oocyte RNA compared to cumulus, and were conserved across other mammalian species. Size distribution of polyadenylated RNA after amplification was similar for oocytes and cumulus. Effects of heat stress on total and polyadenylated RNA, RNA size distribution, and individual transcripts important for meiotic maturation and response to heat stress were examined in oocytes and cumulus during maturation, and resultant embryos after fertilization. There was no impact of heat stress during the first 12 h of maturation to alter size distribution of RNA, rRNA ratio, and other endpoints in oocytes or cumulus. Heat stress perturbed the abundance of polyadenylated RNA in oocytes in one study. Abundance of eight examined transcripts was not altered after exposure to elevated temperature, suggesting that the impact of heat stress on oocyte RNA, if any, was subtle. Consequences of elevated temperature exposure during maturation on transcriptomes of oocytes and their surrounding cumulus vestment were investigated using microarray technology. Thousands of transcripts changed in oocytes and surrounding cumulus over meiotic maturation, some in a stage-specific and amplification-dependent manner. Culture at elevated temperature for the first 12 h of meiotic maturation impacted a small proportion of transcripts in matured oocytes and cumulus at 24 h. Alterations suggested perturbations in oocyte mitochondrial function, and intracellular signaling and extracellular matrix production in cumulus. Heat-induced alterations in oocyte mitochondria and cumulus expansion are supported by existing literature. The findings discussed here are informative of heat-induced molecular alterations in oocytes and cumulus and may prove useful for development of strategies to mitigate negative impacts of heat stress on fertility.

An experiment was conducted to determine effects of anti-Salmonella egg yolk antibodies (ASEYA) on shedding and antibiotic resistance of Salmonella enterica Typhimurium and E. coli, growth performance and immunological parameters. Weaned pigs in two replicate trials (n = 132) were randomly assigned to six dietary treatments, including a control diet without additives, apramycin followed by carbadox, oxytetracycline (OXY), egg yolk powder containing ASEYA, egg yolk powder lacking ASEYA, or spray dried plasma protein (SDPP). Treatments were given to pigs on day 3 of the trial and all pigs were intranasally and orally challenged with Salmonella Typhimurium containing a nalidixic acid resistance marker on day 7. Fecal samples were collected on day 0, 7, 8, 12, 14, 21, 58, 88, and 118 for detection of Salmonella and E. coli to determine shedding and antibiotic resistance. Blood samples were collected and rectal temperatures (RT) were measured on day 0, 7, 8, 12, 14, 21, and 28. Blood was analyzed for white blood cell (WBC) counts and serum was analyzed for Salmonella antibody and interleukin-1β (IL-1β). The percentage of pigs shedding Salmonella was lower (P<0.05) for antibiotic treatments compared to other diets; however, resistance was greater (P<0.05) in E. coli from pigs fed antibiotics. Weight gains did not differ between treatments. Pigs fed OXY had lower RT compared to pigs fed SDPP and ASEYA (P<0.05); however, pigs in all groups had higher RT 24 h after challenge (P<0.05) and had decreasing RT by day 12. Concentrations of anti-Salmonellaa antibodies and WBC counts did not differ between treatment groups. Salmonella antibody concentrations increased in all groups beginning on day 14 and continued to increase through day 28 (P<0.05). IL-1β was generally below detection limits. These studies indicate that in-feed ASEYA may not be effective in controlling shedding of Salmonella or improving the performance or health status of pigs challenged with Salmonella likely because ASEYA cannot reach invasive Salmonella that move through routes outside of the GI tract and/or because ASEYA lose activity as a result of animal digestive processes.

Thinning, herbicide release, and prescribed fire have been used to increase forage availability in pine forests for white-tailed deer, rivaling that available in warm-season food plots. Related data are lacking for hardwood forests. I measured forage availability following 7 silvicultural treatments, including controls (C), forest regeneration methods, and Timber Stand Improvement practices in 4 upland mixed hardwood stands, July–September 2007 and 2008. I also measured forage availability in 4 paired warm-season food plots, including soybeans, lablab, and iron-andclay cowpeas, July–September 2007, and three varieties of soybeans, July–October 2008. I compared nutritional carrying capacity (NCC) of selected species and species from the literature at 3 crude protein nutritional constraints (diet) between forest treatments and food plot plantings. For both years of the study, retention cut with fire (RF) and shelterwood with fire (SF) tended to have the greatest NCC, regardless of species list or diet constraint. Understory triclopyr applications killed woody species following retention cut with herbicide, but relative biomass contribution of woody and herbaceous species returned to original levels two years post treatment. Herbicide applications did not increase NCC. Production of forage plantings exceeded forest treatments in 2007, but RF production was similar to 4.6 and 5.6 soybeans in 2008. Lablab, cowpeas, and later-maturing varieties of soybeans maintained production longer than the early-maturing soybean. Lablab and late-maturing soybeans were the most cost effective plantings. Forage plantings were inexpensive compared to forest treatments (excluding shelterwood) in the short-term, but RF was comparable when using species from the literature after 2 years, and becomes more cost effective after 4 years. I encourage landowners interested in increasing available nutrition for white-tailed deer to manage upland hardwood forests using canopy reduction and prescribed fire. When coupled with population reduction, food plots can be an important management practice where deer exceed NCC.