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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

The effect of feeding canola meal on growth performance and nutrient digestibility in pigs

Sanjayan, Nijitha 23 April 2013 (has links)
Three experiments were conducted to determine the nutritive value of black Brassica napus (BBN), yellow Brassica juncea (YBJ) and yellow Brassica napus (YBN) in pig diets. In experiment 1, effect of multi-carbohydrase supplementation on SID of AA in BBN, YBJ and YBN was evaluated in growing pigs. The YBJ had similar SID of AA to BBN and enzyme did not affect SID of most of AA. The second and third experiments investigated the effect of high dietary inclusion of BBN and YBJ on weaned pig performance and nutrient digestibility with enzyme supplementation. The studies showed that weaned pigs can be fed diets containing up to 250 g/kg of either BBN or YBJ. Enzyme supplementation improved the nutrient digestibility. In conclusion, BBN and YBJ had similar digestible nutrient contents and there were no detrimental effects detected when pigs were fed up to 250 g/kg of BBN and YBJ in weaned pigs.
82

mRNA Destabilizing Factor TTP Expression at the Porcine Maternal-Fetal Interface

Khalaj, Kasra 07 September 2013 (has links)
The tristetraprolin family consists of mRNA destabilizing genes that bind to target mRNA and degrade them. In this context, TIS11 gene family is of primary interest in the spontaneous fetal loss seen in pigs. I hypothesized that the tristetraprolin family regulates these genes in this model. Higher levels of the TIS11 family transcripts in endometrium and trophoblast samples from healthy conceptuses at gd20 were found than in tissues from arresting conceptus attachment sites and significantly higher levels of TIS11 family transcripts were expressed in trophoblast samples associated with arresting conceptuses at gd50 compared to healthy endometrium and trophoblast. TIS11 proteins were expressed and localized at both maternal and fetal sides of maternal-fetal interface. These results provide a basis for understanding some aspects of gene regulation by mRNA destabilizing factors such as tristetraprolin at the maternal-fetal interface and how these factors may play a role in porcine pregnancy and fetal loss. / Department of Biomedical Sciences, NSERC, Ontario Pork, Bioniche Life Sciences Inc.
83

The effect of feeding canola meal on growth performance and nutrient digestibility in pigs

Sanjayan, Nijitha 23 April 2013 (has links)
Three experiments were conducted to determine the nutritive value of black Brassica napus (BBN), yellow Brassica juncea (YBJ) and yellow Brassica napus (YBN) in pig diets. In experiment 1, effect of multi-carbohydrase supplementation on SID of AA in BBN, YBJ and YBN was evaluated in growing pigs. The YBJ had similar SID of AA to BBN and enzyme did not affect SID of most of AA. The second and third experiments investigated the effect of high dietary inclusion of BBN and YBJ on weaned pig performance and nutrient digestibility with enzyme supplementation. The studies showed that weaned pigs can be fed diets containing up to 250 g/kg of either BBN or YBJ. Enzyme supplementation improved the nutrient digestibility. In conclusion, BBN and YBJ had similar digestible nutrient contents and there were no detrimental effects detected when pigs were fed up to 250 g/kg of BBN and YBJ in weaned pigs.
84

Long-term effects of dietary high protein on renal health in the pig model

Jia, Yong 16 September 2008 (has links)
The impact of habitually consuming a high protein (HP) diet at the upper limit of the acceptable macronutrient distribution range (AMDR) on kidney health is unknown. The current study was designed to test the hypothesis that long-term consumption of a diet providing 35% of energy as protein will have negative consequences on renal health, as assessed in a pig model. Methods: Adult female, non-pregnant, commercial pigs (Genesus) were randomized to receive either NP (15% energy from protein) or HP (35% energy from protein) isocaloric diets for either 4 or 8 months. Diets contained whole protein sources with an animal: plant ratio of 2:1 in the NP diet to mimic the average Canadian diet. The increased protein in the HP diet was achieved by increasing egg and dairy protein sources. Body composition was measured by dual-energy X-ray absorptiometry. Glomerular volume and kidney fibrosis were evaluated on kidney sections by quantitative image analysis. The inflammatory marker monocyte chemoattractant protein-1 (MCP-1) and the growth factor transforming growth factor beta-1(TGFβ1) were assessed in renal tissue using commercial ELISA kits. Results: Pigs given the HP diet had lower body weights and percentage of body fat. Pigs consuming the HP diet had significantly higher glomerular filtration rates (GFR) and larger kidneys. Renal MCP-1 levels and renal fibrosis also were significantly higher in pigs given the HP diet, while proteinuria and renal TGFβ1 expression did not differ. Conclusion: These findings suggest that, despite the potential benefit of the HP diet on body composition, long-term intakes of protein at the upper limit of the AMDR may compromise renal health in healthy female pigs.
85

An investigation of novel therapeutic and prophylactic tools for Streptococcus suis

Fletcher, Michael John January 2011 (has links)
No description available.
86

Long-term effects of dietary high protein on renal health in the pig model

Jia, Yong 16 September 2008 (has links)
The impact of habitually consuming a high protein (HP) diet at the upper limit of the acceptable macronutrient distribution range (AMDR) on kidney health is unknown. The current study was designed to test the hypothesis that long-term consumption of a diet providing 35% of energy as protein will have negative consequences on renal health, as assessed in a pig model. Methods: Adult female, non-pregnant, commercial pigs (Genesus) were randomized to receive either NP (15% energy from protein) or HP (35% energy from protein) isocaloric diets for either 4 or 8 months. Diets contained whole protein sources with an animal: plant ratio of 2:1 in the NP diet to mimic the average Canadian diet. The increased protein in the HP diet was achieved by increasing egg and dairy protein sources. Body composition was measured by dual-energy X-ray absorptiometry. Glomerular volume and kidney fibrosis were evaluated on kidney sections by quantitative image analysis. The inflammatory marker monocyte chemoattractant protein-1 (MCP-1) and the growth factor transforming growth factor beta-1(TGFβ1) were assessed in renal tissue using commercial ELISA kits. Results: Pigs given the HP diet had lower body weights and percentage of body fat. Pigs consuming the HP diet had significantly higher glomerular filtration rates (GFR) and larger kidneys. Renal MCP-1 levels and renal fibrosis also were significantly higher in pigs given the HP diet, while proteinuria and renal TGFβ1 expression did not differ. Conclusion: These findings suggest that, despite the potential benefit of the HP diet on body composition, long-term intakes of protein at the upper limit of the AMDR may compromise renal health in healthy female pigs.
87

Studies on the cryopreservation of boar spermatozoa and its integration into assisted reproductive technologies

Bathgate, Roslyn Anne January 2004 (has links)
PhD / The aim of this thesis was to investigate the possibility of integrating frozen-thawed boar semen into reproductive technologies and into commercial production of pigs in Australia. This was to be achieved by establishing a semen freezing and AI regime that was of a standard acceptable to industry, and integrating the resultant frozen-thawed sperm into other reproductive technologies, such as flow cytometric sperm sorting and IVF. Initially, a protocol for freezing and thawing boar semen was established, based on the method described by Westendorf et al. (1975) and attempts were made to modify this protocol to improve the post-thaw sperm quality, as determined by in vitro assessment of motility, acrosome integrity and longevity. First, the egg yolk used in the freezing extenders was investigated, and the chicken yolk was replaced with either duck or quail yolk. It was shown that there was no benefit in substituting yolk from duck or quail for the chicken yolk traditionally used in freezing extender. Second, the effect of seminal plasma addition to the freezing extender, or seminal plasma addition to resuspension medium post-thaw was tested. Incorporating whole seminal plasma into the freezing extender at levels above 50% was found to be detrimental to post-thaw sperm quality. Reducing levels to 20% of the final volume improved acrosome integrity, but adversely affected motility of sperm. However, adding 20% seminal plasma to the resuspension medium used after thawing of boar semen had no significant influence on sperm quality compared with resuspension in medium without seminal plasma. The antioxidant catalase, and the iron chelator desferal added to the freezing extender, did not improve post-thaw sperm quality, nor was any benefit seen with addition of these substrates to the resuspension medium post-thaw. However, the bioactive phospholipid PAF and its regulating enzyme PAF:AH appeared to enhance post-thaw motility and acrosome integrity of sperm, respectively, when added to the semen pre-freezing. Unfortunately, due to the restrictions imposed on rPAF:AH as a research drug, it was not possible to test the in vivo effects at this time. After the in vitro experiments were completed, the in vivo fertility of frozen-thawed sperm was tested using the optimal freezing protocol and a novel technology, enabling non-surgical deep intrauterine insemination of sows. The aim was to establish the lowest possible dose of frozen-thawed sperm that could be used, without compromising fertility. Successful pregnancies were achieved with doses as low as 62.5 x 106 frozen-thawed sperm but the farrowing rates were too low to be practicable on a commercial scale. This is the first report of litters born after insemination of such a low dose of frozen-thawed sperm and using the novel DIU insemination technique. However, it was concluded that a double dose of 250 x 106 frozen-thawed sperm was the minimum dose required for maintaining acceptable fertility. Reduction in sperm numbers to such an extent made it possible to consider non-surgical insemination of sex-sorted, frozen-thawed semen. Previously, pregnancies had been achieved only after surgical insemination of sex-sorted boar sperm, or with DIU insemination of unfrozen sperm, immediately after sex-sorting. The low numbers of sex-sorted sperm available restricted the inseminate dose used here to 50 x106 motile sperm. A litter of 5 piglets was born after a low-dose, DIU insemination of sex-sorted, frozen-thawed sperm. This is the first report of piglets born after insemination with sex-sorted frozen-thawed sperm and non-surgical insemination. The low farrowing rate achieved in this experiment prompted the investigation of integrating sex-sorted, frozen-thawed boar sperm into IVF. Morulae were produced after IVF with sex-sorted, frozen-thawed sperm and successfully transferred using non-surgical techniques. This is the first report of pregnancy achieved with non-surgical transfer of embryos produced after IVF and IVC of IVM oocytes with sex-sorted, frozen-thawed boar sperm. Unfortunately, the pregnancy did not hold, and the embryos were lost prior to Day 32, but PCR of non-transferred embryos confirmed successful pre-selection of sex. Overall, this thesis demonstrated that it is still not economically feasible to incorporate frozen-thawed boar semen into the commercial production of pigs although it has considerable application in breeding programmes. However, the development of novel techniques enabling reduction in sperm dose, and for non-surgical transfer of embryos into recipient sows and incorporation of frozen-thawed semen into these technologies means that progress is being made with the integration of reproductive technologies and frozen-thawed semen into the pig industry.
88

Structuring of breeding objectives in the pork supply chain in South Africa

Visser, Daniel Pieter. January 2004 (has links)
Thesis (Ph. D.) (Agricultural Economics)--University of Pretoria, 2004. / Summaries in English and Afrikaans. Title from opening screen (viewed March 14, 2005). Includes bibliographical references.
89

Efeitos do uso de programas de luz e de triptofano suplementar na dieta sobre o desempenho, comportamento e parâmetros de estresse de leitões recém-desmamados / Different light programs and diet supplementary triptophan of weanling piglets

Gomes, Lívea Maria [UNESP] 11 December 2015 (has links)
Submitted by LIVEA MARIA GOMES (livea_pitti@hotmail.com) on 2016-02-02T12:14:18Z No. of bitstreams: 1 Dissertação Lívea M Gomes final com ficha (3).pdf: 1791851 bytes, checksum: eeb7f3ff7c0cffdcdb1eeb86397ed634 (MD5) / Approved for entry into archive by Sandra Manzano de Almeida (smanzano@marilia.unesp.br) on 2016-02-02T13:24:27Z (GMT) No. of bitstreams: 1 gomes_lm_me_bot.pdf: 1791851 bytes, checksum: eeb7f3ff7c0cffdcdb1eeb86397ed634 (MD5) / Made available in DSpace on 2016-02-02T13:24:27Z (GMT). No. of bitstreams: 1 gomes_lm_me_bot.pdf: 1791851 bytes, checksum: eeb7f3ff7c0cffdcdb1eeb86397ed634 (MD5) Previous issue date: 2015-12-11 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O objetivo do presente estudo foi avaliar os efeitos do aumento do nível de triptofano na dieta de leitões desmamados submetidos a diferentes programas de luz. Foram utilizados 72 leitões desmamados aos 21 dias de idade (peso inicial de 6,6+ 2,33 kg). O delineamento experimental foi o de blocos casualisados com 24 dias de duração em esquema fatorial 2 x 2 (PL: 12 ou 23h de luz/dia e dois NT digestível: 2,6 ou 5,2 g de L-Trp / kg de ração pré-inicial 1 (0-14 dias) e de 2,4 ou 4,8 g de L-Trp / kg na dieta pré-inicial 2 (15-24 dias), com 6 repetições e 3 animais por parcela. Foram avaliados o desempenho, glicemia, perfil plasmático do cortisol e comportamento dos animais. A glicose no sangue foi determinada nos dias 0 e 24, e o cortisol nos dias 0 e 8. O comportamento foi observado nos dias 2, 9, 16 e 23. Não houve interação entre PL e NT sobre desempenho e glicose. Nos períodos de 0-14 e 0-24 dias, os tratamentos não influenciaram o ganho diário de peso, consumo diário de ração e glicose no sangue, enquanto que a conversão alimentar melhorou (P<0,05) apenas no período de 0-14 dias para os animais que receberam 12 horas de luz/dia. Os tratamentos não influenciaram a frequência do comportamento “em movimento”, entretanto houve interação entre PL e NT para o cortisol plasmático, frequência dos comportamentos “ócio” e “alimentar”. Leitões que receberam o maior NT apresentaram menor nível de cortisol plasmático (P<0,05), menor comportamento “alimentar” (P<0,05) e maior comportamento “ócio” (P<0,05) em relação aos animais que receberam NT normal quando submetidos ao PL de 23 horas de luz/dia. O uso de PL de 23h de luz/dia não é indicado, entretanto, quando este manejo for adotado o maior nível de triptofano na dieta é recomendado. / The objective of the present study was to avaluate the effects of light programs (LP) and tryptophan levels (TL) in the diet on performance, blood glucose, plasma profile of cortisol and behavior. A total of 72 piglets weaned at 21 days of age (starting weight 2.33 kg 6,6±) was used. The experimental design was randomized blocks with 24 days duration in a factorial 2 x 2 (LP 12 or 23h light / day and two digestible TL: 2.6 or 5.2 g of L-Trp / kg diet on pre-starter 1 (0-14 days) and 2.4 or 4.8 g of L-Trp / kg diet on prestarter 2 (15-24 days), with 6 repetitions and 3 animals per pen. Glucose blood was determined on d 0 and 24, and cortisol on d 0 and 8. The behavior was observed on d 2, 9, 16 and 23. No effects of PL and NT interaction were observed on performance and blood glucose. In periods of 0- 14 and 0-24 days, the treatments did not influence the daily weight gain, daily feed intake and blood glucose, while feed conversion improved (P <0.05) only in the period of 0-14 days for piglets receiving PL 12h light / day. Treatments did not influence the frequency of “moving” behavior, however there was interaction between PL and NT for plasma cortisol, frequency of “feeding” and “lying” behavior. Piglets that received high NT had lower plasma cortisol level (P <0.05), lower “feeding” behavior (P <0 .05) and increased “lying” behavior (P <0.05) compared to animals that received normal NT when subjected to PL 23 hours light / day. The PL 23h light / day isn’t indicated for piglets, but when this happen, highest tryptophan level in the diet is recommended.
90

Effects of sodium, chloride, and sodium metabisulfite in nursery and grow-finish pig diets

Shawk, Dwight Jay January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Robert D. Goodband / Michael D. Tokach / A total of 12,229 pigs were used in nine experiments to determine the effects of Na, Cl, and sodium metabisulfite-based feed additives on pig growth performance. Experiments 1, 2, and 3 were conducted to determine the effects of added dietary salt on growth performance of pigs weighing 7 to 10, 11 to 30, and 27 to 65 kg. The BLL models suggested the optimal dietary added salt concentration to maximize ADG for pigs weighing 7 to 10 and 11 to 30 kg was 0.59% (0.34% Na and 0.58% Cl) and 0.51% added salt (0.22% Na and 0.42% Cl), respectively. There was no evidence to indicate that growth of 27 to 65 kg pigs was improved beyond a 0.10% added salt inclusion (0.11% Na and 0.26% Cl). Experiments 4, 5, and 6 were conducted to determine the effects of source and concentration of Na and Cl on the growth performance of pigs weighing 7 to 12 kg. In Exp. 4, pigs fed an added salt diet that contains a Na and Cl concentration of 0.35% and 0.60% had greater growth performance compared to pigs fed a deficient Na concentration of 0.18%. In Exp. 5, pigs fed a Na concentration of 0.35%, regardless of ion source, had improved ADG compared to pigs fed a Na concentration of 0.13% or 0.57%. In Exp. 6, maximum ADG and G:F could be obtained with a Cl concentration of 0.38% based on the BLL and QP models. Experiments 7, 8, and 9 were conducted to evaluate the effects of Product 1 (Provimi, Brooksville, OH), Product 2 (Nutriquest, Mason City, IA), and sodium metabisulfite (SMB) on the growth performance of nursery pigs weighing approximately 6 to 25 kg. In Exp. 7, pigs fed Product 1 had higher ADG compared to pigs fed the control. In Exp. 8, pigs fed either Product 1 or 2 at the highest concentration and for the longest period of time had greater ADG compared to pigs fed the control diet. In Exp. 9, pigs fed SMB or Product 1 had greater ADG compared to pigs fed a lower concentration of SMB and the control.

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