Browsing by Subject "Pig"
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Item 2013 Allen D. Leman Swine Research Abstracts September 14-17, 2013 Saint Paul, Minnesota, USA(Veterinary Continuing Education, College of Veterinary Medicine, 2013) College of Veterinary MedicineItem 2014 Allen D Leman Conference Recent Research Reports(College of Veterinary Medicine, 2014) College of Veterinary MedicineItem 2015 Allen D. Leman Swine Conference - Recent Research Reports(College of Veterinary Medicine - Veterinary Continuing Education, 2015) College of Veterinary MedicineItem 2017 Allen D Leman Conference Research Abstracts(College of Veterinary Medicine, 2017) College of Veterinary MedicineItem 2018 Allen D. Leman Swine Conference - Abstracts(College of Veterinary Medicine, 2018) College of Veterinary MedicineItem 2018 Allen D. Leman Swine Conference Proceedings 15 – 18 September, 2018 Saint Paul, Minnesota, USA(College of Veterinary Medicine, 2018) College of Veterinary MedicineItem 2019 Allen D. Leman Swine Conference - Abstracts(College of Veterinary Medicine, 2019) College of Veterinary MedicineItem 2020 Allen D. Leman Swine Conference Proceedings, September 19-22, Saint Paul, Minnesota, USA(College of Veterinary Medicine, 2020) College of Veterinary MedicineAllen D. Leman Swine ConferenceItem 2020 Allen D. Leman Swine Research Abstracts, September 19-22(College of Veterinary Medicine, 2020) College of Veterinary MedicineItem 2021 Allen D. Leman Swine Conference Research Abstracts, 18 – 21 September(College of Veterinary Medicine, 2021) College of Veterinary MedicineItem 2021 Allen D. Leman Swine Conference Proceedings, 18 – 21 September, Saint Paul, Minnesota, USA(College of Veterinary Medicine, 2021) College of Veterinary MedicineAllen D. Leman Swine ConferenceItem 2022 Allen D. Leman Swine Conference Proceedings 17 – 20 September, 2022 Saint Paul, Minnesota, USA(College of Veterinary Medicine, 2022) College of Veterinary MedicineItem 2023 Allen D. Leman Swine Conference Proceedings 16 – 19 September 2023 Saint Paul, Minnesota, USA(College of Veterinary Medicine, 2023)Item Allen D. Leman Swine Conference(College of Veterinary Medicine, 2018) College of Veterinary MedicineAllen D. Leman Swine ConferenceItem Allen D. Leman Swine Conference(College of Veterinary Medicine, 2019) College of Veterinary MedicineAllen D. Leman Swine ConferenceItem Allen D. Leman Swine Conference(College of Veterinary Medicine, 2013)Item Allen D. Leman Swine Conference Recent Research Reports(College of Veterinary Medicine, 2015)Item Antibody repertoire dynamics in the changing landscape of infection(2013-05) Schwartz, John CharlesAntibody responses are fundamentally important to effector and memory mechanisms of disease resistance. In order to respond to a nearly infinite array of possible antigens, the antibody repertoire must be suitably diverse. To achieve this necessary high level of diversity, the antibody repertoire has evolved a unique recombinatorial system consisting of a large number of gene segments that can recombine in different combinations to yield an astronomical array of potential antigen-binding structures. Understanding the antibody repertoire of swine (Sus scrofa) can inform about host genetic differences that may affect disease susceptibility and resistance. Also, it may allow identification of antibody molecules that are important in the host immune response against specific pathogens. Such knowledge could potentially be used in the future to develop selective breeding programs for animals that possess desirable immunological traits, and to screen for specific antibody molecules that are of either therapeutic or diagnostic importance. Knowledge of antibody repertoire diversity in swine has heretofore been lacking. While most previous studies have focused heavily on understanding the heavy chain repertoire by analyzing hundreds of cDNA clones, there have been few investigations of the porcine light chain repertoire. This study was designed to characterize the organization and complexity of both the kappa and lambda light chain loci in the pig genome. Findings revealed extensive allelic variation between both homologous pairs of chromosomes in a single sow and suggested non-crossover homologous recombination (i.e. gene conversion) as a potential evolutionary mechanism to explain at least part of that variation. Armed with this new information, and with that from the previously characterized heavy chain locus, antibody variable region amplicon libraries were generated from lymphoid tissues of pigs either infected (n=2) or mock-infected (heavy chain, n=2; light chain, n=3) with the major swine pathogen, porcine reproductive and respiratory syndrome virus (PRRSV). It is hypothesized that the major anti-PRRSV antibody responses would be detectible in infected animals compared to their control counterparts. Approximately a half-million reads for each heavy and light chain library were generated. From this data, diversity of the expressed antibody repertoire was assessed, including gene segment usage and allelic variability, and anti-PRRSV responses. As predicted, due to biological necessity, the heavy and light chain repertoires possessed a rich array of putatively functional antibody transcripts (heavy chain richness estimate, 3x105 molecules; kappa light chain, 1.5x105; lambda light chain, 2.3 x 105), despite being restricted in their germline to a small number of functional D and J gene segments, a single heavy chain V gene segment family and four light chain V gene families. Interestingly, a power-law distribution of antibody abundances was detected similar to what has previously been reported in zebrafish (Danio rerio), whereby a small number of antibody sequences are exceptionally common and the vast majority are exceptionally rare. Substantial allelic variation was also detected, most notably in the lambda locus. Four out of 5 pigs possessed a functional copy of a previously undescribed V gene segment (IGLV3-1-1) which substantially contributed to the expressed repertoire of the animals that possessed a copy. Importantly, a small number of antibody sequences were detected which were incredibly abundant (>1% of the entire repertoire) in PRRSV-infected pigs and rare in uninfected pigs. It is hypothesized that these highly abundant antibody molecules are PRRSV-specific. Using the knowledge obtained from these studies, future investigations will examine the repertoire for specific heavy and light chain pairs from PRRSV-infected pigs that can neutralize PRRSV using an antibody yeast-display system. In addition, specific heavy and light chain pairs identified in our expression analysis and deemed putatively PRRSV-specific are to be tested for epitopic specificity against labeled PRRSV as well as individual PRRSV recombinant antigens. This last method represents a potential novel and non-lethal means of generating antigen-specific recombinant antibodies derived from lymphoid tissue of immunized animals.Item Epidemiology of lameness in breeding female pigs.(2011-03) Sukumaran Nair, Santhakumari AnilA low level of sow retention in the herd is a cause for both economic as well as welfare concerns. The results of the study confirmed that a low lactation feed intake, incidence of lameness or health problems, as well as sow-level characteristics such as higher parity and fewer piglets born alive per litter may adversely affect sow longevity. Sows retained with periparturient health problems had reduced longevity and fewer live-born piglets, and fewer such sows had another farrowing. A prospective data analysis indicated that the overall performance of lame sows in terms of the number of pigs born alive during the period of the study was less, compared with that for non-lame sows. Retaining sows with less severe lameness may enable the producer to meet immediate production targets. The findings suggest that sow removal decisions should be judiciously evaluated after farrowing considering the potential long-term losses. Lameness in swine herds should be minimized and if treatment is not an option lame sows should be culled as soon as possible to reduce long-term losses. The results also confirmed the high prevalence of claw lesions in breeding female pigs and their association with lameness, specifically, white line and side wall lesions. The results indicate the possibility of nutritional intervention in minimizing claw lesions. However, there are other factors associated with claw lesion development in pigs. The quality of the floor as well as different bio-mechanical factors operating in lesion development are important here. The space between slats, roughness of the surface, and edge design are critical in claw lesion development. Those factors have not been addressed in this study. Further studies are required to understand the mechanism of lesion development in relation to the housing and management systems in place. This information is vital in formulating the appropriate intervention strategy to minimize the incidence of lameness and to improve sow longevity and performance. The studies in this thesis included data from single herds and therefore the generalization of the results may be restricted owing to the wide variations in management, housing and in genetic lines of sows.Item Evaluation of swine liquid feed system with corn - ethanol co-products(2014-09) Meried, WoldeabTwo experiments were conducted to evaluate the use of ethanol co-products, wet distillers grain (WDG) and condensed distillers soluble (CDS), in a swine liquid feeding system. The first experiment was conducted to evaluate the concentration of DE and ME and the apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of energy and nutrients in WDG and CDS fed to growing pigs. Six dietary treatments were studied by replacing 15% and 30% of a corn soybean meal basal diet with WDG or a mixture of WDG or CDS. The experiment consisted of 10 days of adaptation and 4 days of sample collection. Our results indicated that digestibility of 15% CDS diet was significantly higher (P < 0.05) compared to 30% WDG diet. DE and ME were higher in CDS compared to WDG. There was no significant difference in amino acid AID of diets. Lysine AID value of WDG was 75% which was higher than reported DDGS values. CDS lysine AID was 58%. Higher lysine AID could be because WDG was not exposed to drying, which reduces lysine digestibility in DDGS. The second experiment was conducted to determine the ratio of WDG to CDS on the performance of wean to finish pigs fed via a computer-based automatic liquid feeding system. Four dietary treatments were compared by replacing 20% DDGS in the basal diet with same percentage (20%) of WDG or combination of WDG and CDS. Treatment 1, 20% DDGS, Treatment 2, 20% WDG, Treatment 3, 17% WDG + 3% CDS, and Treatment 4, 14% WDG + 6% CDS. The experiment was conducted from 2 weeks post-weaning to finishing (126 days on trial), using a 5-phase feeding rogram. The overall ADG was 0.912, 0.934, 0.957, and 0.937 kg/d, ADFI on a dry matter basis 2.47, 2.2, 2.26, and 2.24 kg/d, and gain to feed ratio 0.33, 0.37, 0.38, and 0.37, for Treatments 1 to 4, respectively. Overall ADG was higher (P = 0.05) in Treatment 3 compared with the DDGS group. Overall, pigs fed diets containing WDG and/or CDS (Treatments 2, 3, and 4) had lower (P = 0.001) ADFI but higher G:F (P = 0.001) compared with animals fed the control diet containing 20% DDGS. Thus, WDG and the combinations of WDG and CDS have beneficial effect on growth performance compared with DDGS.