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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.
41

The effects of parity and stage of gestation on whole body and maternal growth and feed efficiency of gestating sows

Thomas, Lori Lynn January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Robert D. Goodband / A study was conducted on a commercial sow farm to determine the effects of parity and stage of gestation on growth and feed efficiency of gestating sows. These data were also used to model changes in composition of maternal weight gain and products of conceptus throughout gestation. Feed intake and BW were measured daily from d 5 to 112 of gestation for 712 females. From d 5 to 39 of gestation, ADFI was lowest for parity 3+ sows compared to the other periods of gestation. Parity 2 sows, although provided the same feed allowance, had greater ADFI during the first period than parity 3+ sows. Average daily gain was lowest and G:F was the poorest from d 5 to 39 for each parity group compared with d 40 to 109 of gestation. Parity 1 and 2 sow ADG increased following d 39 of gestation but decreased from d 75 to 109. Parity 3+ sow ADG increased in each subsequent period of gestation. Parity 1 sows had the greatest ADG and G:F in comparison to parity 2 and 3+ sows in each period of gestation. Energy available for maternal growth was estimated after accounting for the energy needed to meet the sow’s maintenance requirement and the energy required for the growth of the conceptus. Following d 39 of gestation, energy available for maternal growth decreased at the expense of maintenance and conceptus requirements in each subsequent period of gestation for each parity group. After accounting for the weight of the conceptus, maternal ADG decreased from d 39 to 74, and increased d 74 to 109 of gestation, regardless of parity. Maternal G:F was greatest for parity 1 sows in most gestation periods. In conclusion, parity and stage of gestation impact sow feed efficiency and maternal growth with parity 1 sows having the greatest weight gain and best feed efficiency.
42

Effect of RU486, a progesterone antagonist, on uterine progesterone receptor, embryonic development and ovarian function during early pregnancy in pigs

Mathew, Daniel J., Lucy, Matthew C. Geisert, Rodney D. January 2009 (has links)
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on December 29, 2009). Thesis advisor: Dr. Matthew C. Lucy and Rodney D. Geisert. Vita. Includes bibliographical references.
43

Vitamin supplementation of sows

Shelton, Nicholas William January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / Jim Nelssen / A total of 701 pigs were used to evaluate effects of natural vitamin E relative to synthetic vitamin E in sow diets, late gestation feeding level on sow reproductive performance, dietary L-carnitine and chromium on sow reproductive performance, and experimental design on nursery pig trial interpretation. As D-α-tocopheryl acetate increased in the sow’s diet, concentrations of α-tocopherol increased (P < 0.03) in sow plasma, colostrum, milk, pig plasma, and pig heart. Regression analysis indicated that the bioavailability coefficients for D-α-tocopheryl acetate relative to DL-α-tocopheryl acetate ranged from 2.1 to 4.2 for sow and pig plasma α-tocopherol, 2.9 to 3.0 for colostrum α-tocopherol, 1.6 for milk α-tocopherol, 1.8 for heart α-tocopherol, and 2.0 for liver α-tocopherol. Overall, this study indicates that the relative bioavailability for D-α-tocopheryl acetate relative to DL-α-tocopheryl acetate varies depending on the response criteria but is greater than the standard potency value of 1.36. Increasing sow gestation feeding level by 0.9 kg from d 90 of gestation through farrowing reduced (P = 0.001) daily lactation feed intake in gilts, but also resulted in improved conception rate in gilts, whereas increasing late gestation feeding level decreased conception rate in sows (interaction; P = 0.03). Increasing late gestation feed intake in gilts also increased (P < 0.02) pig weaning weights during the second parity. Increasing late gestation feeding levels did not improve performance of older sows. Adding L-carnitine and chromium from chromium picolinate to sow gestation and lactation diets reduced (P = 0.01) the amount of sow weight loss during lactation, however, did not improve (P > 0.05) litter size, pig birth weight, or the variation in pig birth weight. Blocking pens of nursery pigs by BW in a randomized complete block design (RCBD) did not improve the estimates for σ2error compared to a completely randomized design (CRD) where all pens were allotted to have similar means and variations of body weight. Therefore, the added degrees of freedom for the error term in the CRD allowed more power to detect treatment differences for the CRD compared to the RCBD.
44

An investigation of the effects of cool dry breathing air on the respiration rate and rectal temperatures of farrowing sows

McGinty, Ralph Jerry. January 1960 (has links)
Call number: LD2668 .T4 1960 K63
45

Effects of increasing phytase in nursery pig diets and determining the impact of increasing lysine in lactating sows

Gourley, Kiah Marie January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Joel DeRouchey / Jason Woodworth / Two experiments using a total of 646 nursery pigs were used to determine the effects of increasing phytase on nursery pig growth performance and bone ash characteristics. Two experiments using a total of 821 sows were used to determine the impact of increasing standardized ileal digestible (SID) lysine (Lys) in lactating sows. Experiment 1 determined the available phosphorus (aP) release of Natuphos E 5,000 G phytase in nursery pigs. Increasing phytase from 0 to 1,000 FTU/kg in phosphorus deficient diets improved nursery pig performance and bone ash characteristics. Using percentage bone ash and formulated phytase concentrations, an equation was developed to predict aP release up to 1,000 FTU/kg of Natuphos E phytase. Experiment 2 was conducted to determine the effect of Superdosing Natuphos E 5,000 G phytase on nursery pig performance and bone ash characteristics. Increasing phytase in diets marginal in P improved pig performance and bone ash values. Increasing phytase in P sufficient diets improved bone ash percent and tended to improve feed efficiency. Experiments 3 and 4 determined the impacts of increasing SID Lys in primiparous and multiparous lactating sows and their litters. In Exp. 3, increasing SID Lys above 0.80% in primiparous sows decreased backfat loss, but had no effect on sow BW loss, ADFI or litter gain. Conception rate at d 30 and percentage born alive tended to improve at 0.95% SID Lys. In Exp. 4 with mixed parity sows, increasing SID Lys to 1.05% increased sow weaning BW, litter gain, and reduced weight loss in lactation. Sow backfat loss increased as SID Lys increased from 0.75 to 1.20%, however loin eye depth loss was reduced as SID Lys increased. Percentage of females bred by d 7 after weaning was improved in primiparous females with increasing SID Lys, however no difference was observed in multiparous sows.
46

Analýza reprodukčních vlastností prasnic ve vybraném chovu

KUČEROVÁ, Marie January 2019 (has links)
The aim of the thesis was to analyse the reproductive parameters of the CLW and CLWxCL sows group in selected breeding group (CLW - Czech Large White, CL - Czech Landrace). Sows, compared to gilts, had more all born piglets born after 100 services (by 118 piglets more after 1st insemination and 116 piglets more after all inseminations). The CLWxCL sows gave birth to 0.10 more all born piglets and 0.21 live piglets more. The highest number of piglets, all and live, was born in the 4th parity. The correlation coefficients between the age at the 1st service and the number of all resp. live-born piglets were low. Only 0.1 live piglets were born to CLW sows with weaning to service interval (WSI) from 5 days compared to WSI to 4 days. In CLWxCL sows, more live-born piglets showed sows with WSI to 4 days compared to sows with WSI from 5 days. The difference was higher, namely 0.8 piglet (P < 0.05). In the case of CLW and CLWxCL sows was confirmed a statistically significant difference in the number of live-born piglets between the sows with a gestation length from 116 days, up to 114 days and 115 days. Most of the piglets were born after AMD 74 boar and the lowest number after AMD 101 boar.
47

Parent-offspring conflict and its implications for maternal housing systems in domestic pigs

Pajor, Edmond A. January 1998 (has links)
No description available.
48

Simultaneous measurement of protein and energy metabolism and application to determine lysine requirements in sows

Samuel, Ryan 06 1900 (has links)
Simultaneous measurements of energy and protein metabolism can provide valuable information about their interactions. Dietary lysine is limiting in typical feedstuffs fed to swine and, therefore, limits protein synthesis. Current recommendations for dietary amino acid and energy intakes may not be reflective of the requirements for modern, highly productive sows and, therefore, invalidate requirement estimates determined according to the factorial approach. Current feeding recommendations suggest a constant amino acid intake throughout gestation. However, the demands for amino acids changes from maternal tissue accretion in early-gestation to fetal, conceptus, and mammary tissue development in late-gestation. This thesis reports the method development associated with simultaneous measurements of energy and protein metabolism and its application to determine dietary lysine requirements in non-pregnant and pregnant sows using the indicator amino acid oxidation method. Two indirect calorimetry systems and an experimental feeding regimen were tested and validated for use in studies of amino acid requirements by stable isotope dilution. Protein and energy balance studies were performed in non-pregnant sows fed two distinct levels of energy and protein intake. The systems reacted appropriately to changes in gas concentrations induced by sow respiration. Protein and energy balance studies were also performed in pregnant and lactating sows fed typical diets. Sows appeared more anabolic during mid-gestation and were catabolic by late-gestation and through lactation, where additional energy intake provided by ad libitum feed intake increased milk energy output. The dietary lysine requirement in non-pregnant sows at maintenance was determined as 49 mg/kg0.75, 30% greater than current recommendations. The dietary lysine requirement was determined to be 10.1 g/d and 16.5 g/d, in early- and late-gestation, respectively. These results suggest that a constant diet formulation for the entirety of gestation is not appropriate. In conclusion, simultaneous measurements of energy and protein metabolism combining indirect calorimetry and stable isotope techniques may be used to define requirements for dietary amino acids in sows. Basic assumptions of the factorial approach to estimate requirements require further investigation, including the dietary lysine requirement. Application of phase feeding for sows during gestation can more correctly meet the demands for amino acids and energy, improving sow longevity. / Animal Science
49

Lytinio ciklo ir patologinės anoestrus būklės metu vykstantys pokyčiai sutrikusios reprodukcijos paršavedžių gimdoje / Changes in the uterus of sows with disturbed reproductive cycle during sexual cycle and pathological anoestrus condition

Karvelienė, Birutė 29 November 2007 (has links)
Pirmą kartą buvo atlikti morfologiniai sutrikusios reprodukcijos paršavedžių endometriumo tyrimai, nustatyti endometriumo paviršinio ir liaukinio epitelio aukščio poky��iai, imuninių ląstelių infiltracija, PR-A ir ERα lokalizacija skirtingų lytinio ciklo stadijų ir patologinės anoestrus būklės metu. Nustatyta gonadotropinių hormonų (FSH, LH) poveikio įtaka progesterono (PR-A) ir estrogenų (ERα) receptorių kiekio ir lokalizacijos pokyčiams. Darbo tikslas: įvertinti įvairių veiksnių įtaką laikotarpio trukmei nuo paršelių atjunkymo iki paršavedžių rujos požymių pasireiškimo ir nustatyti morfologinius pakitimus bei estrogenų receptorių alfa (ERα) ir progesterono receptorių A (PR-A) pasiskirstymą sutrikusios reprodukcijos paršavedžių gimdoje lytinio ciklo ir patologinės anoestrus būklės metu. / Aim of the research: The aim of this research was to evaluate the effect of various factors on the duration of the period from piglets weaning to oestrus manifestation and to define morphological changes and distribution of estrogen receptors (ERα) and progesterone receptors A (PR-A) in the uterus of sows with disturbed reproduction during the oestrus cycle and pathological anoestrus condition. Novelty of the research: Morphological investigations of sows with disturbed reproduction endometrium were carried out for the first time, changes of luminar endometrial epithelium and glandular epithelium height, infiltration of the immune cells, PR-A and ERα localization during different stages of oestrus cycle and pathological anoestrus condition were studied. The effect of the number of gonadotropic hormones (FSH, LH), progesterone (PR-A) and estrogen (ERα) receptors and localization changes was studied.
50

Simultaneous measurement of protein and energy metabolism and application to determine lysine requirements in sows

Samuel, Ryan Unknown Date
No description available.

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