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排序方式： 共有307条查询结果，搜索用时 15 毫秒
61.
E Teller M Vanbelle P Kamatali G Collignon B Page B Matatu 《Journal of animal science》1990,68(11):3897-3904
Four primiparous Holstein-Friesian cows (518 kg average BW) with ruminal and duodenal cannulas were used to examine voluntary intake of direct cut (DC) or wilted (W) grass silage in relation to ruminal characteristics and chewing behavior. Dry matter content of the silages was 17.0 and 38.1%, concentrate DM intake was restricted to 5.0 and 5.3 kg/d, and voluntary DM intake from silages averaged 7.4 and 9.5 kg/d (P = .008), respectively. The acetate/propionate ratio in ruminal fluid decreased from 4.0 on DC to 3.3 on W silage (P = .021). The protein content in milk increased from 26.3 to 27.5 g/liter (P = .042) and the protein yield from 469 to 574 g/d (P = .038). The distribution of concentrates (38% of DM intake) with a mean particle size of .04 cm reduced differences in fecal mean particle size between diets. There was a shift from eating to ruminating on W silage with regard to daily duration (min/d) and number of jaw movements (no./d). However, ruminating index (no./kg DM intake) remained unchanged, irrespective of wilting and chop length of the silages or physiological state of the animals. These results are interpreted to indicate that the time lag for functional density of feed particles in the reticulorumen to increase, as affected by ruminating activity, not rate of reduction of the particle size, limits voluntary intake of grass silage by cattle. 相似文献
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Erik H. Hofmeister DVM Brian F. Thompson MS Benjamin M. Brainard VMD DACVECC DACVA Samantha Kegge DVM Stephanie Kube DVM DACVIM Christine M. Egger DVM MVSc DACVA CVA Carl Jehn DVM Brad Green DVM 《Journal of Veterinary Emergency and Critical Care》2008,18(2):142-152
Objective: To document the clinical practice of cardiopulmonary–cerebral resuscitation (CPCR) among academic veterinarians. Design: Survey. Setting: Eight colleges of veterinary medicine in the United States. Subjects: Two hundred and one academic veterinarians. Interventions: The survey was distributed by hand by the authors into the mailboxes of small animal faculty, residents, and interns. Demographic variables, questions regarding number of cardiopulmonary arrests (CPA) supervised and number successful, do not attempt resuscitation discussions, and Likert‐style questions about client presence during CPCR, appropriateness of CPCR, and CPCR decision‐making were included. Multiple linear regression models were constructed to determine the effect of multiple questions on different target variables of interest. Measurements and main results: Numerous differences were noted based on institution, gender, specialty, and position. Most institutions did not have a standard resuscitation consent form. Most respondents believed the client, house officer, and senior clinician should determine whether to perform resuscitation or not. Quality of life was the most significant determinant of whether to resuscitate or not, followed by long‐term prognosis, then short‐term prognosis. Conclusions: Veterinarians differ in many aspects of their approach to CPA and resuscitation. Creating consensus within the veterinary profession would benefit client service and patient care. 相似文献
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Sam Rivera Brad Lock 《Veterinary Clinics of North America: Exotic Animal Practice》2008,11(1):163-75, viii
The field of reptilian clinical endocrinology is still in its infancy. The thyroid and parathyroid glands are intimately involved with many basic metabolic functions. These glands have been the subject of extensive research studies in reptilian species; however, the effects of abnormal gland function have been poorly documented in clinical cases. These glands play a major role in maintaining physiologic homeostasis in all vertebrates. With the advent of more sensitive assays, it should be possible to measure the small amounts of hormones found in reptilian species. The purpose of this article is to review the literature regarding clinical endocrinology of the thyroid and parathyroid glands in reptiles. 相似文献
66.
Prabhu Balan Yuan H. Brad Kim Adam D. Stuart Robert Kemp Maryaan Staincliffe Cameron Craigie Mustafa M. Farouk 《Animal Science Journal》2019,90(8):1060-1069
The objective of this study was to determine the effect of two different freezing rate then thaw‐aging regimens on the quality attributes of lamb loins. The loins were randomly allocated to one of five different freezing/thawing/aging regimes: fast‐(FF1A0) and slow‐(SF1A0) frozen only; fast‐(FF1A2) and slow‐(SF1A2) frozen then thaw‐aged for 14 days; aged for 14 days never frozen (A2). FF1A2 samples had a significantly higher water‐holding capacity compared to the slow frozen regardless of further aging periods. FF1A2 samples had lower (p < 0.05) shear force values than A2 and higher (p < 0.05) water‐holding capacity compared to the SF1A2. Fast freezing resulted in more intracellular cryo‐damage, whereas slow freezing resulted in extracellular cryo‐damage. FF1A0 and SF1A0 samples had lower (p < 0.05) myofibrillar proteins degradation. This study demonstrated that fast freezing then thaw‐aging can result in an improved water‐holding capacity and tenderness through the minimization of extracellular ice crystal formation, reduction in purge and drip losses, and improved proteolysis in thawed lamb. 相似文献
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Brad Leuwerke Pravina Kitikoon Richard Evans Eileen Thacker 《Journal of veterinary diagnostic investigation》2008,20(4):426-432
Swine influenza virus is an economically important pathogen to the U.S. swine industry. New influenza subtypes and isolates within subtypes with different genetic and antigenic makeup have recently emerged in U.S. swineherds. As a result of the emergence of these new viruses, diagnosticians' ability to accurately diagnose influenza infection in pigs and develop appropriate vaccine strategies has become increasingly difficult. The current study compares the ability of subtype-specific commercial enzyme-linked immunosorbent assays (ELISA), hemagglutination inhibition (HI), and serum neutralization (SN) assays to detect antibodies elicited by multiple isolates within different subtypes of influenza virus. Pigs were infected with genetically and antigenically different isolates of the 3 major circulating subtypes within populations of swine (H1N1, H1N2, and H3N2). Serum was collected when all pigs within a group collectively reached HI reciprocal titers >or=160 against that group's homologous challenge virus. The antibody cross-reactivity of the sera between isolates was determined using ELISA, HI, and SN assays. In addition, the correlation between the 3 assays was determined. The assays differed in their ability to detect antibodies produced by the viruses used in the study. The results provide important information to diagnostic laboratories, veterinarians, and swine producers on the ability of 3 common serological assays used in identifying infection with influenza in pigs. 相似文献
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