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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.
251

Studies on the epidemiology of Dictyocaulus viviparus (Bloch, 1782) infection in cattle.

Gupta, Ramesh Prasad. January 1971 (has links)
No description available.
252

Physiological effects of sudden ration changes in dairy cattle /

Vandersall, John Henry January 1959 (has links)
No description available.
253

Genetic and phenotypic associations of various physiological measurements in cattle and their usefulness in the comparative evaluation of sires.

Richardson, Don Orland January 1961 (has links)
No description available.
254

Some physico-chemical, immunological and electrophoretic properties of bovine seminal plasma and their implications in the reproductive process /

Wilson, Edward Matthew January 1969 (has links)
No description available.
255

Comparison of selection indexes for economic merit in dairy cattle /

Lin, Ching-Yonn January 1976 (has links)
No description available.
256

The effect of insecticide impregnated ear tags on cattle weight gain and fly population

Lynch, Gary L January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
257

PUT OPTIONS ON LIVE CATTLE FUTURES CONTRACTS AND ALTERNATIVE MARKETING STRATEGIES

Shuaibi, Abdulaziz Mohamed, 1960- January 1987 (has links)
The main objective of this study was to evaluate alternative marketing strategies involving options on live cattle futures contracts during the period of 1966-85. To predict the option premiums that would have occurred at various points in this period of time, the study did research on market premiums of options on live cattle futures contracts from October 30, 1984, to November 22, 1985. The research showed that actual premiums conform closely to the premiums estimated by the Black model of option pricing. The generalized stochastic dominance with absolute risk aversion function intervals is demonstrated in the study in order to make the evaluation. The results showed that under different risk preferences, the commodity options provide the dominant alternative for cattle producers. Options provided protection from losses resulting from falling cash price and in some cases raised average income of hedgers.
258

Studies on the incidence of bovine parasitic bronchitis in Quebec.

Gupta, Ramesh Prasad. January 1968 (has links)
No description available.
259

The rational development of improved in vitro maturation of bovine oocytes

McDowall, Melanie Lisa January 2004 (has links)
In vitro embryo production has vastly improved over the past decade through the study of the in vivo environment and the metabolic requirements of embryos. In contrast, in vitro oocyte maturation ( IVM ) culture conditions have remained relatively unchanged and are suboptimal. The aim of this thesis was to create improved systems for bovine IVM by studying the metabolic profiles and requirements of intact cumulus oocyte complexes ( COCs ) during IVM and determining the ion and energy substrate composition of bovine follicular fluid ( FF ). Glucose, pyruvate and oxygen consumption of bovine COCs increased 2 - fold over the 24 h IVM period, with glucose being the preferred energy substrate. While initially the majority of glucose consumed by COCs is metabolised via glycolysis ( Llactate production ), a considerable proportion of glucose is used as a substrate for extracellular matrix ( ECM ) synthesis towards the end of IVM. Glucosamine ( an intermediate substrate of hyaluronic acid ) supplementation of IVM media lead to decreased glucose consumption and incorporation into ECM during FSH - stimulated expansion. Biochemical analyses of bovine FF demonstrated that the concentration of some ions and energy substrates varied with follicle size. Although follicular glucose concentrations increased with follicle size, levels were ~ 2 - fold lower than that found in Tissue Culture Medium ( TCM199 ), the most commonly employed medium for bovine IVM. Synthetic Follicular Fluid Medium ( SFFM ) was created, based on the FF data and also contained glucosamine. Two different glucose concentrations were examined, 2.3 mM glucose to represent physiological concentrations and 5.6 mM glucose, the same concentration as is in TCM199. Culturing COCs in different glucose concentrations manipulated the completion of nuclear maturation and this was dependant on concentration, gonadotrophin supplementation and the timing of media changes, demonstrating the importance of this substrate to meiotic competence. Although glucosamine had no effect on oocyte nuclear maturation, supplementation during IVM led to a dose - dependent decrease in blastocyst rates. The detrimental effects of glucosamine manifested during early cleavage and were associated with a 0.6 - fold decrease in protein synthesis levels within the oocyte compared to oocytes cultured in media with no glucosamine, suggesting a detrimental effect on developmental competence. Interestingly oocytes cultured in media containing glucosamine and EGF had significantly higher protein synthesis compared to the control group. The biochemical profiles of COCs during IVM and FF were determined and used to create new media that allowed manipulation of oocyte nuclear maturation but compromised cytoplasmic maturation. Further research is required to optimise SFFM and to investigate the detrimental effects of glucosamine on developmental competence. / Thesis (Ph.D.)--Medical School, 2004.
260

Transovarial transmission efficiency of Babesia bovis by Rhipicephalus (boophilus) microplus

Howell, Jeanne Marie, January 2007 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, May 2007. / Includes bibliographical references.

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