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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.
121

Influence of Feeding Pooled Colostrum or Colostrum Replacement on IgG Levels and Evaluation of Animal Plasma as a Milk Replacer Protein Source

Mowrey, Coleen Marie 12 May 2001 (has links)
Newborn Holstein (n = 48) and Jersey (n = 30) calves were studied to compare the absorption of immunoglobulin G (IgG) from maternal colostrum (n = 39) or a colostrum replacement product derived from bovine serum (n = 39). Calves were also fed milk replacer with (n = 38) or without (n = 40) animal plasma to 29 d of age to determine the effect of plasma protein on IgG status, health, and growth. Colostrum or colostrum replacement was fed at 1.05 and 13.5 h of age and provided a total of 250, 180, 249, or 186 g IgG for Holsteins and Jerseys fed replacement or colostrum, respectively. Milk replacer (12.5% DM) was fed at 31% of metabolic birth weight (2 feedings/d). Jugular blood was sampled at 0 h, 24 h, and weekly to determine plasma IgG. At blood collection calves were weighed and measured to determine growth. Health scores, fecal scores, and grain intake were measured daily. Mean plasma IgG at 24 h did not differ between calves fed colostrum (13.78 ± 0.39 g/L) and replacement (13.96 ± 0.38 g/L). Average daily gain, wither height, hip height, body length, heart girth, health, and incidence of diarrhea were not different between treatment groups. Plasma IgG and performance were not affected by addition of animal plasma to milk replacer. The colostrum substitute successfully replaced colostrum as the source of IgG for newborn calves. Animal plasma was an acceptable source of protein, but did not enhance growth or immunity. / Master of Science
122

Intensified Calf Feeding Programs for Purebred and Crossbred Calves

Phillips, Josette M. 30 August 2004 (has links)
In the first experiment, 132 Jersey calves were assigned to one of three diets on three farms. Diet 20/20, 28/25, and 28/20 were milk replacers (MR) consisting of 20%, 28%, and 28% CP, and 20%, 25%, and 20% fat, respectively. Diet 20/20 was reconstituted at 10% DM solids, whereas diets 28/25 and 28/20 were reconstituted at 12.5% DM solids. Body weight, body length, hip height, wither height, heart girth, and hip width were measured weekly. An initial plasma sample was analyzed for IgG concentration to test for passive immunity. Calves remained on study for 8 wk. Body weight gain, ADG, total weight gain, and stature measurements were greatest for calves fed 28/25 and lowest for calves fed diet 20/20, whereas calves fed 28/20 were intermediate. In the second experiment, 70 calves were assigned to one of two treatments. Calves included purebred Holsteins, Jerseys, and crossbred reciprocals. Calves were assigned to diet 20/20, which was reconstituted to 10% DM solids or diet 28/20, which was reconstituted to 13% DM solids. Body weight, body length, hip and wither heights, heart girth, and hip width were measured weekly. Plasma samples were collected weekly for analysis of PUN, glucose, and total proteins. Body weight gain, ADG, and total weight gain were greatest for calves fed 28/20 and least for calves fed diet 20/20. Therefore, feeding calves a 20/20 MR at 10-15% of their BW results in lower BW gain, ADG, total weight gain, and stature measurements. / Master of Science
123

Viability of waste milk pasteurization systems for calf feeding systems

Scott, Michael Chase 27 June 2006 (has links)
The objective of this study was to determine amount and composition of waste milk (WM) generated by 13 dairy farms and to measure effectiveness of on-farm pasteurizers. Waste milk was sampled bi-weekly from three farms located in North Carolina (NC) for 28 weeks and twice from ten farms in California (CA) in June 2005 and Jan. 2006. Amount of waste milk generated ranged from 2.48 – 9.84 L/calf/d. Standard plate count (SPC) of waste milk before pasteurization averaged 17 million cfu/ml on NC farms and 1.6 million cfu/ml on CA farms. Pasteurizers failed to deactivate alkaline phosphatase in 16%, and <5% of the time in NC and CA. California WM had lower post pasteurized SPC (13,000 cfu/ml) than NC farms (430,000 cfu/ml). A feeding trial was conducted to evaluate supplementing WM with 28% protein: 20% fat milk replacer (28:20) when WM is insufficient relative to calf demands. Treatment (TRT) 1 calves received M for 28d and then 28:20 until weaning at 56d. Treatment 2 calves received 28:20 for 28d and then milk until weaning. Treatment 3 calves received 28:20 for the entire period Four periods of time were evaluated; the total period, first four weeks (P1), transition period (TP), in which calves were switching diets, and until weaning (P2). Treatment 1 ADG was higher during TP as compared to TRT 2. Results demonstrated that similar growth rates through 8 weeks of age was achieved with either combination of M and 28:20 or only 28:20 fed on an isocaloric basis. / Master of Science
124

Economic analysis of early weaning for dairy calves using prestarter and varied milk sources in California, Kansas and Wisconsin

Nelson, Leiann Heid. January 1984 (has links)
Call number: LD2668 .T4 1984 N44 / Master of Science
125

Net Returns to Alternative Weaning Dates in Beef Cow-Calf Operations

Savage, Gregory Edward 01 May 2010 (has links)
There is sparse research literature in agricultural economics regarding early weaning as a potential alternative production/marketing strategy. The objective of this research is to estimate and analyze the impacts on net returns of alternative weaning dates for Tennessee cow-calf operations including alternative post-weaning treatments for calves. The Decision Evaluator for the Cattle Industry (DECI) simulation program was used for this study to produce outputs such as calf numbers, gender, and weights, other output including cow weights and body condition score, both at calving and at weaning, and pregnancy percentages. Forty-two simulations were run for average and summer drought weather, weaning at an average age of 135, 165, 195, 225, 255, and 285 days and selling at weaning or after a 60 or 90-day drylot backgrounding period. Prices for steers, heifers, and culled cows from 1995-2008 were taken from market reports. Costs were derived from University of Tennessee Extension Beef and Forage Budgets and USDA-NASS. The outputs from DECI were combined with prices to result in total revenues. Subtracting the costs of feed, interest, veterinary and medical, and marketing resulted in return to land, labor, management, and risk to the enterprise. The results of this study revealed that under average weather conditions in East Tennessee, marketing at weaning in November yielded the highest net return. Weaning in August and backgrounding for 60 days yielded the lowest net return with the base 90-cow herd. Under summer drought conditions, marketing at weaning in August resulted in the highest net return. Weaning in November and marketing after a 90-day backgrounding period yielded the lowest net return. Under the conditions used in this study, the only time early weaning makes economic sense is when herd size is increased for June or July weaning or under drought conditions when August (195 days) weaning and sale is optimal. Several limitations of this study imply that additional research is required on this topic before definite conclusions can be drawn.
126

Net Returns to Alternative Weaning Dates in Beef Cow-Calf Operations

Savage, Gregory Edward 01 May 2010 (has links)
There is sparse research literature in agricultural economics regarding early weaning as a potential alternative production/marketing strategy. The objective of this research is to estimate and analyze the impacts on net returns of alternative weaning dates for Tennessee cow-calf operations including alternative post-weaning treatments for calves.The Decision Evaluator for the Cattle Industry (DECI) simulation program was used for this study to produce outputs such as calf numbers, gender, and weights, other output including cow weights and body condition score, both at calving and at weaning, and pregnancy percentages. Forty-two simulations were run for average and summer drought weather, weaning at an average age of 135, 165, 195, 225, 255, and 285 days and selling at weaning or after a 60 or 90-day drylot backgrounding period. Prices for steers, heifers, and culled cows from 1995-2008 were taken from market reports. Costs were derived from University of Tennessee Extension Beef and Forage Budgets and USDA-NASS. The outputs from DECI were combined with prices to result in total revenues. Subtracting the costs of feed, interest, veterinary and medical, and marketing resulted in return to land, labor, management, and risk to the enterprise. The results of this study revealed that under average weather conditions in East Tennessee, marketing at weaning in November yielded the highest net return. Weaning in August and backgrounding for 60 days yielded the lowest net return with the base 90-cow herd.Under summer drought conditions, marketing at weaning in August resulted in the highest net return. Weaning in November and marketing after a 90-day backgrounding period yielded the lowest net return.Under the conditions used in this study, the only time early weaning makes economic sense is when herd size is increased for June or July weaning or under drought conditions when August (195 days) weaning and sale is optimal. Several limitations of this study imply that additional research is required on this topic before definite conclusions can be drawn.
127

Breed trends and effect of breed on sale price of lots of beef calves marketed via video auction

McCabe, Esther Dorice January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Karol Fike / The United States beef cattle industry is continuously evolving and changing to meet buyer demands while considering environment factors for production. Cow-calf producers make decisions within their herds that impact their profitability. Previous research shows producers can add value to beef calves through management and marketing decisions in areas such as genetics, herd health, and nutrition. It is well documented that there are numerous factors that influence the sale price of beef calves, no matter the venue through which they are sold. Historically, steer calves sold for a greater price compared to heifer calves. Apparent breed composition also influences value of lots of beef calves. Black-hided calves recently sold for a greater sale price than calves of other hide colors due to perceived differences in potential performance. Calves with Bos indicus influence usually sell for a lower price than other breed types. Marketing of beef calves through video auction allows sellers to market lots of calves to a buyer basis nationwide. A national market provides a basis for buyer preferences and potential national trends for changes in characteristics valued by buyers. Evaluation of national breed composition trends can indicate potential changes in the industry. The opportunity to evaluate if and how breed description as described by producers influenced calf sale price from 1995 through 2016 was available through a livestock video auction service. Chapter 1 is a review of the literature and an overview of the beef industry and factors affecting sale price of lots of beef calves. Chapter 2 is an analysis of breed composition influencing sale price for lots of steer calves and lots of heifer calves. Chapter 3 investigates national and regional breed description and sire breed trends over a 23-year period.
128

Use of Analgesic Combination Morphine-Lidocaine-Ketamine in Holstein Calves Undergoing Ventral Midline Herniorrhaphy

Hartnack, Amanda Katherine 09 September 2014 (has links)
No description available.
129

Linear body measurements and other birth observations on beef calves as predictors of preweaning growth rate and weaning type score

Flock, Dietmar K. 06 February 2013 (has links)
Since birth type showed only a low association with weaning type and preweaning gain, it is of no practical interest whether or not type at birth can be expressed by certain body proportions, which themselves are not high enough correlated with the two weaning traits to be of any predictive value. The high association between birth weight and the linear body measurements suggests that birth weight is as good a measure of a calf's merit at birth as any other birth observation. Birth weight should be considered a useful selection criterion for Angus and possibly Hereford calves, but not for Shorthorns, except that extremely small calves should not be kept as breeding stock. Neither body measurements nor type at birth can be recommended as selection criteria as their use would not be likely to result in an improvement of the more important weaning traits. / Master of Science
130

Évaluation des pratiques d’élevage des fermes laitières au Québec qui sont des facteurs de risque associés au prix des veaux laitiers lors de la vente à l’encan

Ferraro, Salvatore 12 1900 (has links)
Le terme veaux laitiers se réfère aux veaux mâles et femelles non retenus pour le remplacement et vendus en jeune âge. L’objectif de cette étude était d’évaluer l’association entre les caractéristiques et les pratiques de la ferme et le prix final de veaux laitiers lors de leurs mises en marche dans deux encans québécois. Les éleveurs des fermes d’origine des veaux ont été contactés pour répondre à un questionnaire sur les caractéristiques et les pratiques de leur ferme. L’association entre les caractéristiques et les pratiques de la ferme et le percentile de la médiane du prix des veaux a été évaluée via un modèle multivariable de régression linéaire. Un total de 509 éleveurs a été contacté, 433 ont accepté de participer et 409 questionnaires ont été retenus pour les analyses statistiques. Les fermes ont vendu en médiane deux veaux (entre 1 et 19) et la majorité (82%) était de race Holstein. Leur prix était positivement associé à une production moyenne par vache/an supérieure à 11 000 litres et à la présence sur la ferme de trois travailleurs et plus s’occupant des veaux. Leur prix était négativement associé à la vaccination des vaches pour la diarrhée néonatale, l’absence de désinfection du cordon ombilical des veaux, l’interdiction aux transporteurs d’entrer dans les bâtiments de la ferme et à l’utilisation de ripe de bois comme litière des veaux. Les résultats démontrent que les caractéristiques et les pratiques de la ferme d’origine sont associées au prix des veaux laitiers / The term surplus calf defines the male calves and heifers culled within two weeks of life. The objective of this study was to evaluate the associations between the characteristics and the practice of the dairy farms and the price of surplus calves. Their selling price (CAD/kg) were recorded in two-auction markets between 2019 and 2020. The farms who sold calves during the study were contacted to answer the survey. The possible association between the characteristics and the practices of the farms and the median percentile of surplus calves’ selling price per farm was assessed using a multivariable linear regression model. A total of 509 farmers were contacted, 433 of them have accepted to be enrolled and 409 questionnaires were retained for statistical analysis. The median of the surplus calves sold by the farm was two (between 1 and 19) and the majority were Holstein (82%). The covariates that were positively associated with the median percentile of surplus calves’ selling price per farm were an average milk production per cow/year superior to 11,000 liters and the presence of the farm of three or more workers available to take care of calves. Their selling price was negatively associated with vaccination of cows for neonatal calf diarrhea, no disinfection of the navel of newborn calves, no forbid transporters to entry in the farm’s buildings and use of wood shaving as bedding for surplus calves. The results show the association between the characteristics and practices of farms and the price of surplus calves.

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