Browsing by Subject "Pigs"

Now showing 1 - 9 of 9
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    Abstract of Fourteenth Annual Animal Nutrition Short Course, September 14-15, 1953.
    (University of Minnesota, Institute of Agriculture., 1953-09)
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    Dietary evaluation of low-oligosaccharide soybean meal in pigs
    (2012-10) Pangeni, Devi P.
    To evaluate the potential benefit of low oligosaccharide soybean meal (LOSBM) in the diets of early-weaned pigs, three experiments were performed by replacing conventional soybean meal (cSBM) with LOSBM. Low oligosaccharide soybean meal has a higher CP content than SBM. The interaction between LOSBM and the use of fishmeal and spray dried porcine plasma (FM/SDPP) was also evaluated during the nursery phase of the study. The objective of study 1 was to evaluate the effect of LOSBM on growth performance, viscosity of intestinal content, intestinal morphology, organ weights and blood urea nitrogen (BUN) in early-weaned pigs during 14 d post weaning. Four phase 1 diets used were corn-SBM or corn-LOSBM with or without supplementation of FM/SDPP in a 2 × 2 factorial arrangement. There was no interaction between FM/SDPP and the sources of soybean meal for the parameters studied. Treatments had no effect on growth performance, organ weight and intestinal length. No effect of treatment was observed for ileal crypt depth, jejunal crypt depth and ileal villi height. However, jejunal villi height was greater (P = 0.01) in pigs with cSBM diet. Levels of BUN were higher (P = 0.01) in pigs fed LOSBM diet and replacing cSBM with LOSBM reduced (P = 0.01) the viscosity of intestinal content. The objective of study 2 was to determine the apparent total tract digestibility (ATTD) and apparent ileal digestibility (AID) of DM, energy, N, ADF and NDF by grower pigs fed corn-LOSBM and corn-SBM diets in two different adaptation periods (5d and 7d). Grower pigs cannulated at ileo-cecal junction were randomly allotted to one of two dietary treatments. Treatment 1 consisted of conventional corn-SBM diet and treatment 2 consisted of corn-LOSBM. Replacing SBM with LOSBM improved percent AID of DM (P < 0.01), energy (P < 0.01) and ADF (P < 0.01). Similarly pigs fed LOSBM had improved ATTD of DM (P < 0.01), energy (P < 0.01) and ADF (P < 0.01). Study 3 was conducted to determine the effect of replacing cSBM with LOSBM on growth performance and carcass characteristics of pigs from wean to finish. Dietary treatments were fed in 6 phases based on a 2 × 3 factorial arrangement with 2 levels of FM/SDPP (none or phases 1 to 3) and 3 levels of LOSBM inclusion (none, phases 1 to 3, or phases 1 to 6). There was no interaction between FM/SDPP in nursery and LOSBM in any phase for ADG, ADFI or G:F. Replacing SBM with LOSBM resulted in gains in piglets feed efficiency (phase 1 and 2, P< 0.01) and piglets fed FM/SDPP had improved ADG (P < 0.01) and feed efficiency (P < 0.05) only in phase 2. Neither treatment factor affected live weight, carcass weight, fat or loin depth, percent lean, percent yield, grade or value. The early improvements did not affect overall performance from wean to finish, nor did they affect the final carcass characteristics. In summary, replacing cSBM with LOSBM did not affect the performance of the pigs. It seems that young pigs can better tolerate LOSBM as it decreased the viscosity of intestinal content. Improved ileal digestibility of nutrients in LOSBM in compared to cSBM may be beneficial for pigs. Key words:
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    Effects of dietary Peroxidized lipids on the growth performance and metabolic oxidative status of nursery pigs
    (2014-06) Hanson, Andrea R.
    Supplemental lipids and lipid rich ingredients with high concentrations of polyunsaturated fatty acids may peroxidize during processing and storage. Exposure to heat, air, moisture, and other pro-oxidants accelerate peroxidation, and peroxidation is impeded by antioxidants. Metabolic oxidative stress occurs when pro-oxidants overload the antioxidant capacity of an animal. This dissertation explores the impact of lipid peroxidation in DDGS and corn oil on the growth performance, health, and metabolic oxidative status of young pigs. An extensive summary of published research revealed that feeding peroxidized lipids to pigs and broilers reduced growth, feed intake, and gain efficiency by 11.2, 7.5, and 4.3%, respectively, and resulted in metabolic oxidative stress. Similar, negative effects were confirmed in 2 additional experiments which evaluated increasing dietary levels of peroxidized corn oil. Our findings suggest the magnitude of reduction in growth depends on the conditions used to peroxidize corn oil. However, in a separate experiment, the dietary inclusion of a highly peroxidized source of DDGS did not affect the growth performance of nursery pigs. Numerous compounds are produced and degraded during peroxidation, and some of these products have been associated negatively animal health and performance. The dynamic nature of peroxidation creates a challenge for nutritionists and formulators assessing the feeding value of dietary lipids. An in vitro experiment was conducted to compare several indicators of peroxidation when heating refined corn oil at either 185°C or 95°C. Results suggest that thermal processing and storage conditions should be considered when selecting indicators of peroxidation, but this information is seldom available. An additional experiment was conducted to assess peroxidation in distillers corn oil and DDGS during storage in the presence or absence of antioxidants. Peroxidation increased during 28 d of storage at 38°C and 90% relative humidity. However, peroxidation was attenuated partially by antioxidants. Our results clearly demonstrate negative effects of dietary peroxidized lipids on the growth performance and metabolic oxidative status of nursery pigs. Future research is necessary to develop an accurate model for predicting reductions in growth performance and metabolic oxidative status when feeding diets containing peroxidized lipids.
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    Monitoring of phenotypic and genotypic changes in antimicrobial resistance in clinical swine bacterial isolates circulating in the U.S.
    (2019-08) Hayer, Shivdeep Singh
    Starting 2017, a Veterinary Feed Directive was implemented in food animal production in the U.S. This directive prohibits the extra-label use and use of medically important antimicrobials for growth promotion. Analysis of long-term trends of antimicrobial resistance (AMR) can help in evaluating the success of such policies. The objectives of this dissertation were to monitor phenotypic and genotypic changes in antimicrobial resistance in clinical swine bacterial isolates (Escherichia coli, Streptococcus suis, Actinobacillus suis, Pasteurella multocida and Haemophilus parasuis) circulating in the U.S. between 2006 to 2016. For E. coli, the prevalence of resistance to most of the antimicrobials remained constant or changed only modestly, with the exception of enrofloxacin resistance which increased from nearly 0% in 2006 to 21% in 2016. For S. suis and P. multocida, prevalence of resistance did not change drastically except for a few antimicrobials. For A. suis and H. parasuis, statistically significant changes were estimated for several antimicrobials. However, a lack of clinical breakpoints or epidemiological cut-offs hindered in the making any clinical or epidemiological inferences. E. coli isolates resistant to ceftiofur and enrofloxacin were selected and whole genome sequencing was conducted on these isolates. Nearly 25% of the ceftiofur resistant E. coli isolates carried ESBL genes and 24% of enrofloxacin resistant isolates carried qnr genes. These genes have been reported only rarely in food animals in USA. Select plasmids carrying ESBL genes were assembled and these were similar to ESBL plasmids present globally. Additionally, these isolates were also found to be carrying mcr-9 and fosA7 genes, which have not been reported in food animals in USA previously. In addition to these studies, a systematic review on global prevalence of AMR in E. coli of swine origin is also presented. This review highlights the disparity between AMR prevalence in high income versus lower-middle income countries and a clear lack of harmonization in studies conducted worldwide.
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    A pilot study of the epidemiology of Staphylococcus aureus in multiple site swine production
    (2013-08) Linhares, Leticia Caldas Monteiro
    Staphylococcus aureus (S. aureus) is a common colonizer of both humans and pigs (Lowy, 1998; Frana, 2012). The ability of S. aureus to acquire genes that confer resistance to multiple drugs has further elevated its importance to public health (Cuny and Witte, 2008a). In particular, clones of S. aureus that are resistant to methicillin and other beta-lactam antimicrobials (MRSA) are a major clinical problem, and the discovery of MRSA in livestock populations has raised concerns about the potential importance of livestock as reservoirs of MRSA (Voss et al., 2005).However, the importance of pigs in S. aureus transmission to humans and clinical disease is yet to be determined (Cuny and Witte, 2008b). Most recent studies of pigs have focused on MRSA, and there have been no comprehensive studies of the epidemiology of S. aureus (MSSA and MRSA) in pigs. Despite being considered ubiquitous in production animal facilities (Frana, 2012), S. aureus ecology in livestock production farms is poorly documented. Most recent research has used selective enrichment methods to study MRSA in swine populations, rather than generic S. aureus. S. aureus can be isolated from several anatomic sites of pigs, as well as from air, environmental samples and persons having contact with pigs. In fact, isolation of S. aureus in air samples from swine barns suggests this is likely an important route of exposure for people working in livestock facilities (Gibbs et al., 2006; Oppliger et al., 2012). Overall, the limited information on the ecology of S. aureus in the pork production chain limits the ability of the swine industry to understand and communicate the risks to public health in an informed manner.The core rationale for this thesis was that there has been no prior systematic effort to describe the occurrence of S. aureus in swine production systems. The vast majority of studies have focused on MRSA strains using selective culture methods, and/or focused on a limited number of matrices. The objective was therefore to obtain preliminary data on the occurrence of S. aureus in pigs, people, environmental and air samples on pig farms and some insight into the distribution of the organism in the swine farm milieu. Thus, a pilot study of the epidemiology of S. aureus in multiple site swine production was conducted.
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    Senecavirus A in pigs: Epidemiology, Transmission, and Diagnosis
    (2022-11) Milanez Preis, Guilherme
    Senecavirus A (SVA) has been linked to several swine vesicular disease outbreaks worldwide. Several countries have already reported the presence of the virus, and the risk of new cases is constant due to the movement of animals, people, and materials, among other potential SVA-carrying agents, between pig herds. Despite the disruptions and confusion that SVA can cause due to its clinical similarities to high-consequence foreign animal diseases, such as foot-and-mouth disease, little is known about its epidemiology and control. The main objective of this thesis was to provide new information on the epidemiology, transmission, and detection of this virus.Understanding the extent of SVA spread within a country and the risk factors associated with its exposure are the first steps toward building control strategies. Therefore, a study was designed to estimate the seroprevalence of the virus in the United States (U.S.). The seroprevalence of SVA in breeding and growing pig farms was relatively low, with 17.3% of breeding and 7.4% of growing pig farms being classified as positive. Among sow farms, the disposal of dead animal carcasses through rendering was associated with SVA seropositivity. The information about how SVA transmits between farms is scarce. Therefore, another study was conducted to evaluate the role of fomites in the indirect transmission of SVA between pig populations. Study personnel carrying fomites had direct contact with SVA-infected pigs and moved to different rooms housing SVA-naïve animals under low, medium, and high biosecurity standards. The virus was successfully transmitted to the rooms under low biosecurity standards, evidencing the role of fomites in the indirect transmission of SVA between pig populations. A third study focused on understanding the methods to detect the virus at different stages of infection, which is crucial for developing control and surveillance efforts. It is known that SVA-infected pigs shed the virus for approximately 21 to 28 days after infection. The study was designed to compare the results from oral swabs, rectal swabs, tonsil swabs, and tonsil scrapings in diagnosing SVA in experimentally-inoculated animals up to 48 days after infection. Tonsil scrapings were the only sample type where SVA was found at the late stages of the infection. At the same time, other sample types, such as rectal swabs, were easier to collect and had higher chances of SVA detection at earlier stages of infection. Developing an alternative aggregate sampling method would facilitate the detection of SVA at the population level. The fourth study in this chapter aimed to estimate the average number of SVA-positive weeks in processing fluids (PF) after an SVA outbreak. After longitudinally sampling 10 breeding farms, PF samples were estimated to remain positive on average for 11.8 weeks after an outbreak. Testing of PF may be a cost-effective method to detect SVA presence in breeding farms. In summary, this thesis has uncovered and provided novel information on the epidemiology of SVA and the knowledge gaps that remain. The information generated will serve as the foundation work for the development of further studies as well as monitoring, surveillance, and control strategies.
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    Sow lameness and claw lesions evaluation.
    (2010-07) De Pita, Alejandrina Da Silva
    Abstract summary not available
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    The Use of Novel High Protein Distillers Dried Grains in Swine Diets
    (2018-08) Yang, Zhaohui
    Innovative processing technologies have been developed and implemented in some dry-grind ethanol plants in the U.S. ethanol industry. Some of these technologies have resulted in the production of novel high protein corn co-products. However, there are limited data on the metabolizable energy and standardized ileal digestibility of amino acids of these new high protein co-products for swine. In addition, these novel high protein ingredients have unique characteristics, such as high fiber and high leucine concentrations that might limit their use in swine diets. Results from this thesis indicated that novel high protein corn co-products added at up to 30% of nursery and growing-finishing pig diets may reduce pig growth performance and compromise carcass composition. Further studies are needed to investigate the strategies to optimize the use of novel high protein corn co-products in swine diets.
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    Transmission and control of influenza virus in pig populations
    (2013-09) Allerson, Matthew William
    Influenza A virus (IAV) is a common cause of respiratory disease in pigs and has been detected in pigs in most pig producing regions of the world. Influenza A viruses are able to infect many different animal species, including pigs, humans, and birds. In addition, influenza A viruses may be transmitted between pigs and other species, including humans. Following the first clinical description of influenza virus infection in pigs in the United States in 1918, research targeting influenza A viruses in pigs and other animal species has intensified quite rapidly. At the same time, control of influenza in swine farms has become increasingly challenging as there are many diverse influenza virus lineages present in the United States. Influenza control is further hindered by the relatively small amount of information assessing influenza virus transmission and within herd infection dynamics as compared to other research disciplines. This thesis aimed to 1) describe within herd influenza virus infection dynamics and temporal patterns of infection in breeding and grow-finish herds, 2) assess the prevalence and temporal patterns of influenza virus infection in weaning-age pigs on commercial swine breeding herds, 3) evaluate influenza virus transmission via indirect routes, and 4) determine the impact of vaccination and maternally derived immunity on influenza virus transmission in weaning-age pigs. The findings of this thesis have advanced the understanding of influenza virus transmission and epidemiology in swine. Researchers, veterinarians and swine producers may utilize this information to investigate influenza virus infections within herds and to help mitigate influenza virus infections.