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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.
101

Compara??o da toxicidade de Vicia villosa e Vicia sativa na alimenta??o de bovinos / Comparison of the toxicity of Vicia villosa and Vicia sativa in feed for cattle

VERONEZI, Luciane Orbem 27 July 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-01-24T19:09:14Z No. of bitstreams: 1 2016 - Luciane Orbem Veronezi.pdf: 3213369 bytes, checksum: 660b54c56b80e667f1e30d110c395df3 (MD5) / Made available in DSpace on 2018-01-24T19:09:14Z (GMT). No. of bitstreams: 1 2016 - Luciane Orbem Veronezi.pdf: 3213369 bytes, checksum: 660b54c56b80e667f1e30d110c395df3 (MD5) Previous issue date: 2016-07-27 / CAPES / In this study the epidemiology, clinical signs, macroscopic and microscopic lesions related to spontaneous and experimental intoxication by Vicia villosa and the evaluation of the possible toxicity of Vicia villosa in cattle were characterized. The systematic granulomatous disease (SGD associated with vetch) was verified in 7 localities distributed in Paran?, Santa Catarina and Rio Grande do Sul States, with main feed that includes oats and/or ryegrass in association and V. villosa and/or ryegrass associated with Vicia sativa, and in lower quantity. All cattle that developed the disease were cows, lactating and Dutch. The SGD associated with vetch was reproduced in six lactating Dutch cows, by supplying green V. villosa in the trough and V. villosa and ryegrass pasture. In the other experimental groups (group 3, V. villosa / V. sativa/cows, grazing; group 4, V. sativa/cows, grazing; group 5, V. villosa/V. sativa/heifers and group 6, V. villosa/heifers, grazing) do not verified clinical and pathological alterations related to the SGD associated with vetch. Six cows developed the SGD, one cow presented a leigh clinical condition (group 2/cow 6/V. villosa, pasture), four cows developed a moderated clinical condition (group 1, cows 1 and 2/V. villosa/trough and group 2, cows 4 and 5/V. villosa, grazing), and just one cow presented a severe clinical condition (group 2, cow 3/V. villosa/pasture. V. villosa was toxic to cattle and produced a chronic granulomatous disease when ingested in amounts greater than 38.2 g/kg/day for 71 days, or in direct grazing for a period of more than 28 days The main clinical signs consisted of alopecia and cutaneous crusts, pruritus, fever, conjunctivitis, diarrhea, reduction of milk production and weight loss. Macroscopically, multiple white-grayish nodules were observed, specifically in the lymph nodes, kidneys and heart, and histology revealed a granulomatous infiltrate composed of macrophages, lymphocytes, giant cells, epithelioid cells, plasma cells and eosinophils. When ingested by young cattle, the V. villosa pasture, for a period of 68 days, do not produce clinical modifications. When ingested by cows with high milk yield, the V. sativa pasture, for a period of 78 days, does not produce chronic granulomatous disease. Ingestion of V. villosa for a long time led to low production rates, such as low milk production, low reproduction rates and predisposition to infection diseases. In the bromatological analysis, the presence of phytate, in low levels, in the samples of Vicia used in experimental works, in different phases of the culture was determined. The biochemical blood and feces results showing lower amounts of serum sinc and loss of Ca and Zn feces in animals poisoned by V. villosa, that developed granulomatous disease in severe and moderate conditions, possibly indicated the presence of a metabolic disorder in the pathogen of the disease. / No presente estudo caracterizou-se a epidemiologia, os sinais cl?nicos, as les?es macrosc?picas e microsc?picas da intoxica??o espont?nea e experimental por Vicia villosa, bem como a avalia??o da poss?vel toxicidade de Vicia sativa em bovinos. A doen?a granulomatosa sist?mica (DGS ervilhaca-associada) foi verificada em 7 propriedades distribu?das nos Estados de Santa Catarina, Paran? e Rio Grande do Sul, onde a alimenta??o principal era aveia e/ou azev?m consorciados com V. villosa e/ou de azev?m consorciado com V. villosa e em menor quantidade V. sativa. Todos os bovinos que desenvolveram a doen?a eram vacas, em lacta??o e da ra?a Holand?s. A DGS ervilhaca-associada foi reproduzida em seis vacas holandesas em lacta??o, atrav?s do fornecimento de V. villosa verde no cocho e em pastagens de V. villosa e azev?m. Nos demais grupos experimentais (grupo 3, V. villosa/V. sativa/vacas, pastejo; grupo 4, V. sativa/vacas, pastejo; grupo 5, V. villosa/V. sativa/novilhas e grupo 6, V. villosa/novilhas, pastejo) n?o verificou-se altera??es cl?nicas e patol?gicas relacionadas a DGS ervilhaca-associada. Das seis vacas que desenvolveram a doen?a granulomatosa sist?mica, uma vaca apresentou quadro cl?nico leve (grupo 2/vaca 6/V.villosa, pastejo), quatro vacas desenvolveram o quadro moderado da doen?a (grupo 1, vacas 1 e 2/V. villosa/cocho e grupo 2, vacas 4 e 5/V.villosa/pastejo) e apenas em uma vaca verificou-se o quadro grave da doen?a (grupo 2, vaca 3/V.villosa/pastejo). V. villosa foi t?xica para bovinos, produzindo doen?a granulomatosa cr?nica quando ingerida em quantidades superiores a 38,2g/kg/dia, por um per?odo de 71 ou, em pastoreio direto por um per?odo superior a 28 dias. As principais manifesta??es cl?nicas consistiam em ?reas de alopecia e crostas na pele, coceira, febre, conjuntivite, diarreia, queda na produ??o de leite e perda de peso. Macroscopicamente verificaram-se m?ltiplos n?dulos branco-acinzentados principalmente em linfonodos, rins e cora??o, e na histologia estes caracterizavam um infiltrado granulomatoso composto por macr?fagos, linf?citos, c?lulas gigantes, c?lulas epitelioides, plasm?citos e eosin?filos. As pastagens de V. villosa quando ingerida por bovinos jovens, por um per?odo 68 dias n?o produziu altera??es cl?nicas. As pastagens de V. sativa quando ingerida por vacas de alta produ??o leiteira por um per?odo de 76 dias n?o produziu doen?a granulomatosa cr?nica. A ingest?o de V. villosa por per?odos prolongados conduziu a baixos ?ndices produtivos como: baixa produ??o leiteira, baixos ?ndices reprodutivos e pode predispor o surgimento de doen?as infeciosas. Na an?lise bromatol?gica determinou-se a presen?a de fitato, em pequenas quantidades, nas amostras de Vicia utilizadas na experimenta??o, em diferentes fases do seu crescimento. Os resultados das an?lises bioqu?micas de amostras de sangue e fezes evidenciaram baixas quantidades s?ricas de zinco e excessivas perdas fecais de Ca e Zn nos animais intoxicados por V. villosa que desenvolveram a doen?a granulomatosa na forma moderada e grave, indicando um poss?vel envolvimento de dist?rbios de ordem metab?lica na patogenia da doen?a.
102

The Energy Expenditure of Heifers Grazing Crested Wheatgrass Rangeland in West-Central Utah

Havstad, Kris M. 01 May 1981 (has links)
The free-roaming ruminant requires energy for the demands of vii grazing, traveling and thermoregulation that are not required by its confined counterpart. Literature estimates of these additional costs range from 10 to 170 percent above maintenance. The uncertain magnitude of this increased demand and the factors that contribute to it impede the ability of the rangeland ruminant nutritionist to establish guidelines for the energy requirements of the free-roaming herbivore. This study was designed to estimate the energy expenditure of yearling Angus heifers while grazing a declining supply of available crested wheatgrass forage (Agropyron cristatum) on rangeland in west-central Utah. Free-ranging energy expenditure was estimated twice for four heifers during each of five ten-day periods during June, July August and early September, 1979. These estimates were obtained using the carbon dioxide entry rate technique. In addition, total fecal output, dietary crude protein and dietary in vitro organic matter digestibility were estimated for animals grazing the 20- hectare crested wheatgrass pasture. From these data, daily forage intake was calculated. The level of available forage during each period was estimated using the ocular weight-estimate technique applied on forty 1 m2 circular plots. Energy expenditure was estimated as 161 (with a confidence interval of ±43) kcal·kg body weight-.75.d-1 (n=10), and was independent of the decline in available forage from 880 to 284 kg dry matter·hectare-1 that occurred over the course of the grazing season. Daily intake was 54.5 grams (organic matter basis) per unit body weight.75 for the 305 kg heifers. Daily intake was independent of the supply of available forage. During early July, 1980, crested wheatgrass was harvested as hay and fed to 260 kg yearling Angus heifers in metabolism stalls in a thermoneutral and constantly illuminated laboratory. Daily feeding levels were set at 54.5 grams (organic matter basis) per unit body weight.75. Energy expenditure under these conditions was estimated as 111 (±12) kcal·kg body weight-.75·day-1 , 6 kcal per unit body weight.75 greater than the mean estimate of the fasting metabolism rate. The latter estimate was obtained following a 48-hour fast. These estimates of maintenance and fasting metabolism were combined to provide a mean estimate of 110 (±10) kcal·kg body weight-.75·day-1 (n=14). Of the 45 percent (51 kcal·kg body weight-.75·day-1) increase in the estimated energy expenditures by heifers under free-roaming conditions, 50 percent was attributed to the energetic cost of grazing. A daily average 9.2 hours were spent in this activity. The energetic cost of grazing was assumed as 0.82 kcal·kg body weight-1·hour-1 spent grazing. Daily travel was estimated as 3.9 km at an assumed energetic cost of 0.58 kcal·kg body weight-1·km-1. This accounted for a 20 percent estimated increase in energy expenditure. Average daily temperatures were generally between 12°C and 30°C and thermoregulatory demands were not considered as a substantial energetic expense. The remaining 30 percent (12 kcal) of the additional increment due to free-roaming conditions could not be explained.
103

Chromosome Abnormalities as a possible Cause of Reduced Fertility in Dairy Heifers

Henderson, Stanley L. 01 May 1990 (has links)
Chromosome evaluations were made on leukocyte blood samples from 169 phenotypically normal nulliparous Holstein heifers. These were from three different reproduction groups collected in sets of threes from 10 different herds in the western United States. Group 1, the control group, consisted of heifers diagnosed pregnant after one or two breedings; Group 2 consisted of heifers diagnosed pregnant after three or four breedings; and Group 3 consisted of heifers diagnosed open after four or more breedings. Metaphase chromosome spreads used in these analyses were obtained through 72-hour leukocyte cultures from heparinized whole blood. Processed cells were dropped onto a slide, air-dried, and stained with Giemsa. Chromosomes were then counted and X chromosomes were identified. A total of 1, 597 cells was evaluated, with 1,439 cells having counts of 60 chromosomes each. Thirty cells had less than 58 chromosomes, 31 cells had 58 chromosomes, 75 cells had 59 chromosomes, 14 cells had 61 chromosomes, and 8 cells had more than 61 chromosomes (9 .98% were different than 60). All counts of other than 60 chromosomes were isolated cases and were not identified as abnormalities. Only two cells from two separate heifers contained what may have been sex chromosome abnormalities. No persistent chromosomal defects were observed among the 169 heifers.
104

Transforming shrimp and crab waste into dairy heifer feed

Evers, Dale J. 30 August 1994 (has links)
The goal of these experiments was to ensile combinations of shrimp or crab waste with perennial ryegrass straw and analyze it for silage quality and ruminal degradability. The rapid deterioration of seafood wastes required initial preservation prior to ensiling to minimize odor production and protein breakdown. Eight experiments were conducted to preserve, ensile and test the ruminal degradability of shrimp and crab waste. The first three experiments attempted to preserve crab waste with the addition of 0 to 15% molasses for 14 days or shrimp waste with molasses at 0 to 25% for 6 or 21 days. In all three experiments, the addition of molasses decreased crude protein, crude protein loss, and pH, and improved odors. Although a lactic acid fermentation began, the high pH and acetic and butyric acid concentrations indicate fermentation was not completed. The crude protein loss and odor production warrants a quicker method of preservation. In Experiments 4 and 5, shrimp or crab waste were combined with 6 levels of salt from 0 to 12.5% for 6 days. The addition of salt decreased crude protein percentage, crude protein loss and all volatile fatty acid concentrations while increasing the pH and improving the odors. The 7.5% salt-preserved shrimp and crab wastes had 29.9 and 30.7% crude protein, respectively. Experiments 6 and 7 ensiled the salt-preserved shrimp and crab waste with grass straw, molasses and an inoculant in 15 L mini-silos for 40 days. Shrimp waste was combined at 37, 47 or 52% dry matter while crab waste was combined at 43, 46 or 52% dry matter. Molasses at 0, 10, or 20% and an inoculant were added to both silages. The 47% dry matter, 20% molasses non-inoculated shrimp silage had the following analysis on a dry matter basis: crude protein, 16.1%, acid detergent fiber. 27.0%. acetic acid, 1.37%. butyric acid, .01%, lactic acid, 7.17%, and a pH of 7.0 and a good silage odor. The 46% dry matter, 10% molasses, inoculated crab silage had the following analysis on a dry matter basis: crude protein. 21.1%, acid detergent fiber, 19.6%, acetic acid, 1.68, butyric acid, .00%, lactic acid, 2.86% and a questionable odor score. In Experiment 8, the ruminal degradability of shrimp and crab waste and shrimp and crab silage were tested using two fistulated steers and sampled at nine time points ranging from 0 to 96 hr. Shrimp waste had a ruminally available DM%, CP%, ADF%, and %ADIN of 36.9, 43.0, 44.2, and 43.6% respectively. Crab waste had a ruminally available DM%, CP%, ADF%, and %ADIN of 38.9, 53.3, 41.0, and 33.0% respectively. Ensiling the shrimp and crab wastes improved the percentage of ruminally available DM and CP and lowered the percentage of ruminally available ADF and ADIN. This indicates that ensiling promotes the degradation of chitin and the release of nitrogen to the rumen. Effective preservation of shrimp and crab waste with salt and then adequate fermentation of the wastes with grass straw, molasses and inoculant has increased the ruminal degradability of the wastes and led to successful transformation of the waste into a dairy heifer feedstuff. / Graduation date: 1995
105

Determining biological sources of variation in residual feed intake in Brahman heifers during confinement feeding and on pasture

Dittmar (III), Robert Otto 15 May 2009 (has links)
Objectives were to characterize residual feed intake (RFI) and determine the phenotypic correlation between performance, feed efficiency, and other biological measurements in Brahman heifers, as well as the relationship between RFI determined in confinement and measurements of grazing activity on pasture. Three separate 70 d feeding trials were performed, and RFI was determined as the residual between actual and predicted dry matter intake (DMI) for a given level of production. Brahman heifers (n = 103; 5-to-9 mo of age) were individually limit-fed a pelleted 12% CP complete ration daily in Calan gates. Weekly body weight (BW) and DMI data were collected, and predicted DMI was determined by linear regression of actual DMI on mid-test metabolic BW. Ytterbium chloride was used to evaluate digestive kinetics, and fecal samples were collected to determine fecal volatile fatty acids (VFA) concentration and determine apparent dry matter digestibility (DMD) utilizing acid insoluble ash as an internal marker. Measurements of temperament were evaluated on all heifers at weaning. High (n = 6) and low (n = 6) RFI heifers (Exp. I) grazed fescue and ryegrass to determine variation in grazing behavior, DMI, and apparent DMD. Data from all three experiments were pooled, and RFI was not correlated with average daily gain (ADG), DMI, BW, partial efficiency of gain, feed conversion ration, fecal VFA concentration, or any measures of temperament. There were no significant differences in digestive kinetics between the RFI efficiency groups. Fecal samples taken for acid detergent insoluble ash (ADIA) determination were not collected at frequent enough intervals to account for weekly variation in fecal ADIA concentration. Pasture measurements were not different between the efficiency groups for heifers evaluated for grazing behavior, as well as estimated intake as a proportion of BW, or apparent DMD. Results of this study suggest that Bos indicus cattle appear to have similar efficiency traits as Bos taurus and Bos indicus influenced cattle, making this measure of efficiency equally as valid for use in both types of cattle. This indicates that selection based on RFI can be made to increase feed efficiency without affecting ADG or BW in Brahman cattle.
106

Determining biological sources of variation in residual feed intake in Brahman heifers during confinement feeding and on pasture

Dittmar (III), Robert Otto 10 October 2008 (has links)
Objectives were to characterize residual feed intake (RFI) and determine the phenotypic correlation between performance, feed efficiency, and other biological measurements in Brahman heifers, as well as the relationship between RFI determined in confinement and measurements of grazing activity on pasture. Three separate 70 d feeding trials were performed, and RFI was determined as the residual between actual and predicted dry matter intake (DMI) for a given level of production. Brahman heifers (n = 103; 5-to-9 mo of age) were individually limit-fed a pelleted 12% CP complete ration daily in Calan gates. Weekly body weight (BW) and DMI data were collected, and predicted DMI was determined by linear regression of actual DMI on mid-test metabolic BW. Ytterbium chloride was used to evaluate digestive kinetics, and fecal samples were collected to determine fecal volatile fatty acids (VFA) concentration and determine apparent dry matter digestibility (DMD) utilizing acid insoluble ash as an internal marker. Measurements of temperament were evaluated on all heifers at weaning. High (n = 6) and low (n = 6) RFI heifers (Exp. I) grazed fescue and ryegrass to determine variation in grazing behavior, DMI, and apparent DMD. Data from all three experiments were pooled, and RFI was not correlated with average daily gain (ADG), DMI, BW, partial efficiency of gain, feed conversion ration, fecal VFA concentration, or any measures of temperament. There were no significant differences in digestive kinetics between the RFI efficiency groups. Fecal samples taken for acid detergent insoluble ash (ADIA) determination were not collected at frequent enough intervals to account for weekly variation in fecal ADIA concentration. Pasture measurements were not different between the efficiency groups for heifers evaluated for grazing behavior, as well as estimated intake as a proportion of BW, or apparent DMD. Results of this study suggest that Bos indicus cattle appear to have similar efficiency traits as Bos taurus and Bos indicus influenced cattle, making this measure of efficiency equally as valid for use in both types of cattle. This indicates that selection based on RFI can be made to increase feed efficiency without affecting ADG or BW in Brahman cattle.
107

Galvijų masės ir amžiaus įtaka skerdenų išeigai ir kokybei / The influence of mass and age of cattle on the carcass meat yield and quality

Moleikaitienė, Sida 19 May 2014 (has links)
Rezultatai ir aptarimas: Darbas atliktas 2011-2014 metais LSMU Veterinarijos akademijos Gyvulininkystės katedroje ir X gyvulių skerdykloje. Darbui panaudota 2011-2012 metais gyvulių skerdykloje paskerstų galvijų duomenys: 423 buliai, 492 telyčios ir 3975 karvės. Duomenys statistiniam tyrimui buvo susisteminti: galvijų svoris suskirstytas 50 kg intervalais, amžius suskirstytas 2 mėn. intervalais. Tyrimo metu nustatėme, kad galvijų masės didėjimas didino skerdenų išeigą. Bulių grupėje koreliacinis ryšys tarp priešskerdiminės masės ir skerdenos išeigos buvo didžiausias r=0,4 (p<0,001), lyginant su telyčių (r=0,3; p<0,001) ir karvių (r=0,2; p<0,01) minėtais rodikliais. Galvijų masė įtakoja skerdenų kokybę. Didėjant gyvulio masei, didėja jų raumeningumas bei riebumas ir jie priskiriami aukštesnei skerdenų klasifikacijos klasei. Bulių, telyčių ir karvių grupėse riebumo ir raumeningumo klasės yra susijusios ir statistiškai reikšmingos (p<0,01-p<0,001). Didėjant galvijų amžiui didėja ir jų skerdenų išeigos. Bulių ir telyčių grupėse koreliacinis ryšys tarp jų amžiaus ir skerdenos išeigos yra silpnas (r=0,1; p<0,05), tačiau vis tiktai didėjant amžiui pastebimas skerdenos išeigos didėjimas (p<0,05). Analizuojant koreliacinius ryšius tarp karvių amžiaus ir skerdenos išeigos yra nustatytas neigiamas ryšys (r=-0,3; p<0,01). Tai rodo, kad didėjant karvių amžiui skerdenos išeiga mažėja. Galvijų amžius turi teigiamos įtakos bulių ir telyčių svoriui bei skerdenų kokybei. Esant didesnei gyvulio... [toliau žr. visą tekstą] / The outcomes and considerations: The paper was carried out from 2011 to 2014, in LSMU Veterinary Academy, Livestock Department and X cattle slaughterhouse. For the paper was used the data of slaughtered cattle in the slaughterhouse from 2011 to 2012 : 423 bulls, 492 heifers and 3975 cows. The data was systematised for the statistics research: the weight of the cattle was divided at 50 kg intervals, the age was divided at 2 month intervals. In the research was established that the increase of the mass of the cow increased the yield of the carcass meat. The correliation between the mass of the meat before the slaughter has taken place and the carcass meat was the greatest in the group of bulls r=0.4 (p<0.001), in comparison to the group of heifers (r=0.3; p<0.001) and cows (r=0.2; p<0.01) above the pointed out quality indicators. The mass of the cattle influences the quality of the carcass meat. The increase of cattle mass increases their muscularity and fatness and as a result they are attributed to the higher carcass meat classification class. In the groups of bulls, heifers and cows the fatness and muscularity classes are connected and significant for statistics (p<0.01; p<0.001). When cattle grow older the carcass meat yield increases. In the groups of bulls and hifers the correlation between their age and carcass meat yield is weak (r=0.1; p<0.05), however, when the cattle grow older there is observed an insignificant increase in the carcass meat yield (p<0.05). While... [to full text]
108

Peripartaler Energie- und Fettstoffwechsel sowie Insulinsensitivität von Färsen bei unterschiedlicher Aufzuchtintensität

Goerigk, Daniela Isabell 19 May 2011 (has links) (PDF)
In den vorliegenden Studien wurde der Fragestellung nachgegangen, wie sich unterschiedliche Fütterungsprotokolle während der Aufzuchtperiode auf den peripartalen Energie- und Fettstoffwechsel und die Insulinsensitivität von Färsen auswirken. Besonderes Augenmerk lag dabei auf der Frage, ob der „Revised Quantitative Insulin Sensitivity Check Index“ (RQUICKI) bei Färsen sinnvoll angewendet werden kann, um eine Aussage hinsichtlich der Insulinsensitivität zu treffen. Auch mögliche Auswirkungen auf das Konzeptionsalter, den Kalbeverlauf, die Milchleistung und die postpartale Morbidität wurden untersucht. Aus 46 Kälbern der Rasse Deutsche Holstein wurden drei Fütterungsgruppen gebildet. Gruppe 1 (n = 18) wurde gemäß den Richtlinien der GfE energetisch optimal gefüttert (Kontrollgruppe), Gruppe 2 (n = 14) wurde intensiv und Gruppe 3 (n = 14) restriktiv gefüttert. Im Abstand von zwei Wochen wurden die Tiere jeweils gewogen. Aus den vorliegenden Daten wurde die durchschnittliche tägliche Körpermassezunahme berechnet. Außerdem wurde zehn, sechs, drei und eine Woche vor der Kalbung sowie zwei Wochen nach der Kalbung die Rückenfettdicke (RFD) sonografisch bestimmt. Weiterhin wurden das Alter bei erfolgreicher Konzeption, Kalbeverlauf sowie Daten der Kälber, Milchleistungsprüfungsdaten und Rastzeit erfasst. Vor und nach der Kalbung wurde aus der Vena caudalis mediana Blut entnommen. Aus dem Serum wurden die Konzentrationen der folgenden Parameter bestimmt: Insulin, Insulin-like growth factor 1 (IGF-1), Glukose, freie Fettsäuren (FFS), Bilirubin, Cholesterol, Harnstoff, Betahydroxybutyrat (BHB) sowie Gesamteiweiß. Erkrankungen im postpartalen Zeitraum, wie Endometritis, Mastitis, Stoffwechselstörungen, Erkrankungen des Bewegungsapparates sowie Zyklusstörungen wurden ebenfalls in die Studien miteinbezogen. Zur Bestimmung der Insulinsensitivität wurde das Rechenmodell „Revised Quantitative Insulin Sensitivity Check Index“ (RQUICKI) verwendet. Unter Einbeziehung der Serumkonzentrationen von Glukose, Insulin und FFS lautete die Formel RQUICKI = 1/[log (Glukose) + log (Insulin) + log (FFS)]. Ein niedriger Index-Wert bedeutet eine verminderte Insulinsensitivität. Die intensiv aufgezogenen Tiere der Gruppe 2 zeigten mit 13,3 ± 1,0 Monaten ein signifikant (p = 0,003) früheres Konzeptionsalter im Gegensatz zu den Tieren der beiden anderen Gruppen (Gruppe 1: 16,0 ± 1,5 Monate; Gruppe 3: 17,7 ± 1,4 Monate). Eine Woche ante partum wiesen die Tiere der Gruppe 2 eine signifikant (p = 0,022) höhere RFD auf als die Tiere der beiden anderen Gruppen. Der RQUICKI korrelierte eine Woche ante partum signifikant negativ mit der RFD (r = -0,573; p = 0,003). RQUICKI war bei den Tieren der Gruppe 2 eine Woche ante partum signifikant (p < 0,05) niedriger als bei den Tieren der anderen Gruppen. In allen drei Gruppen konnten am dritten Tag post partum die niedrigsten Index-Werte nachgewiesen werden. Aus den errechneten Index-Werten lässt sich für Färsen für die Zeitpunkte eine Woche ante partum sowie vier Wochen post partum ein Referenzbereich von RQUICKI = 0,40 ± 0,04 ableiten. Um den dritten Laktationstag liegt bei Färsen der Referenzbereich von RQUICKI = 0,34 ± 0,02. Die intensiv aufgezogenen Färsen zeigten insgesamt mit 85,7 % die höchste Anzahl an Komplikationen bei der Kalbung, der Unterschied war statistisch allerdings nicht zu sichern. Die unterschiedliche Fütterung wirkte sich weder auf das Geschlecht der Kälber noch auf deren Geburtsgewicht aus. Signifikante Unterschiede (p < 0,05) ergaben sich bei den Serumkonzentrationen von Insulin, IGF-1, FFS und Cholesterol ante partum sowie den Bilirubin- und FFS-Konzentrationen 28 Tage post partum. Es konnten keine statistisch signifikanten Unterschiede bei den Konzentrationen von Glukose, Harnstoff, BHB und Totalprotein ermittelt werden (p > 0,05). Beim Vergleich der 305-Tage-Milchleistung wiesen die Tiere der Gruppe 2 die niedrigste Milchleistung auf. Eine signifikant (p = 0,039) höhere Inzidenz von postpartalen Zyklusstörungen war bei den Tieren der Gruppe 2 erkennbar. Eine Woche ante partum korrelierte RQUICKI signifikant negativ (r = -0,509, p = 0,008) mit dem Auftreten von Zyklusstörungen post partum. Die Untersuchungen haben gezeigt, dass durch die Fütterungsintensität während der Aufzuchtperiode die Zuchtreife, der peripartale Energie- und Fettstoffwechsel einschließlich der Insulinsensitivität, die Milchleistung sowie die postpartale Fertilität beeinflusst werden. Aus der intensiven Aufzucht resultieren eine frühere Zuchtreife, höhere Rückenfettdicken, eine gesteigerte peripartale Lipolyse einschließlich reduzierter Insulinsensitivität, eine verminderte Milchleistung und eine schlechtere Fertilität. / The aim of these studies was to investigate how different diets during the rearing period influence peripartal energy and fat metabolism as well as insulin sensitivity of heifers. Special attention was paid to the question if the „Revised Quantitative Insulin Sensitivity Check Index“ (RQUICKI) could be used to estimate insulin sensitivity in heifers. Possible influences on age at first breeding, calving, milk yield and postpartal morbidity were analysed as well. Furthermore, the aim of this investigation was to prove, if different diets at rearing influence the peripartal insulin sensitivity of heifers. 46 German Holstein calves were randomly divided in three groups. Group 1 (n = 18) was fed with an optimal diet (control group) based on recommendations of the German Society of Nutrition Physiology, group 2 (n = 14) was fed with a highly-concentrated diet and group 3 (n = 14) got a low-concentrated diet. In intervals of two weeks the heifers were weighed. With the obtained data the averaged daily weight gain was computed. In addition, ten, six, three and one week ante partum as well as two weeks post partum the backfat thickness (BFT) was measured ultrasonographically. Age at first breeding, calving, data of the calves, milk yield and interval to first service post partum were recorded, too. Before and after calving blood samples were taken from the Vena caudalis mediana. The concentrations of the following parameters were measured in blood serum: Insulin, insulin-like growth factor 1 (IGF-1), glucose, free fatty acids (FFA), bilirubin, cholesterol, urea, betahydroxybutyrat (BHB) as well as total protein. Furthermore, postpartal diseases like endometritis, mastitis, metabolic disorders, limb diseases and fertility disorders were included. To determine insulin sensitivity a mathematic model called “Revised Quantitative Insulin Sensitivity Check Index” (RQUICKI) was used. Serum concentrations of glucose, insulin and FFA were included in the formula RQUICKI = 1/[log (glucose) + log (insulin) + log (FFA)]. A low index value represents a decreased insulin sensitivity. Intensive reared heifers of group 2 reached age at first breeding (13.3 ± 1.0 months) significant (p = 0.003) earlier than heifers of the other both groups (group 1: 16.6 ± 1.5 months; group 3: 17.7 ± 1.4 months). One week ante partum heifers of group 2 showed significant (p = 0.022) higher BFT than heifers of the other groups. At the same timepoint, RQUICKI correlated significant negative with the BFT (r = -0.573; p = 0.003). In heifers of group 2, RQUICKI was significant lower (p < 0.05) one week ante partum than in heifers of the other groups. In all groups, the index values were lowest three days post partum. Based on the received index values reference ranges for RQUICKI in heifers can be proposed. One week ante partum as well as four weeks post partum the reference range for RQUICKI can be defined as RQUICKI = 0.40 ± 0.04. Three days after calving the reference range can be defined as RQUICKI = 0.34 ± 0.02. The intensive reared heifers show with an overall of 85.7 % the most difficulties at calving, but this was statistically not different. The different diets didn’t influence neither the sex of the calves nor their birth weight. Ante partum, serum concentrations of Insulin, IGF-1, FFA and cholesterol differed significantly (p < 0.05) as well as serum concentrations of bilirubin and FFA differed on day 28 post partum. No significant differences could be determined in serum concentrations of glucose, urea, BHB and total protein (p > 0.05). Heifers of group 2 showed the lowest 305-day milk yield. The incidence of postpartal ovarian diseases was significantly (p = 0.039) higher in heifers of group 2. A significant negative correlation (r = -0.509, p = 0.008) existed between RQUICKI ante partum and the incidence of postpartal ovarian diseases. In conclusion, different diets during the rearing period influence age at first breeding, peripartal energy and fat metabolism including insulin sensitivity, milk yield as well as postpartal fertility. An intensive rearing results in an earlier age at first breeding, increased BFT, enhanced peripartal lipolysis as well as reduced insulin sensitivity, decreased milk yield and poorer fertility.
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Reproductive and lactation performnace of dairy cattle in the Oromia Central Highlands of Ethiopia : with special emphasis on pregnancy period /

Lobago, Fikre, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
110

On repeat breeding in dairy heifers : with special focus on follicular dynamics, ovulation, and oocyte quality /

Båge, Renée, January 2002 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2002. / Härtill 5 uppsatser.

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