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31.
R. C. Hill K. Haynes K. C. Scott S. J. Tucker J. K. Levy P. C. Crawford 《Journal of animal physiology and animal nutrition》2008,92(2):220-220
Upper respiratory infection (URI) is an important cause of morbidity and mortality in shelter cats. Malnutrition, specifically vitamin A deficiency, has been associated with respiratory tract infections in humans in developing countries. The purpose of this study was to determine whether feral cats and cats in shelters have lower serum vitamin A concentrations than pet cats, because it was surmised that a vitamin A deficiency may predispose these cats to develop URI. This was a cross-sectional study in which serum retinol, α-tocopherol, γ-tocopherol and beta carotene concentrations were measured from 48 shelter cats, 56 feral cats, and 42 pet cats, using HPLC. Retinol, α-tocopherol, and γ-tocopherol concentrations were found to be significantly lower in the shelter and feral cat populations than in pet cats (p ≤ 0.0001). There was no evidence of an effect of sex or neuter status on vitamin concentrations. Sick feral cats had a higher beta carotene level than did healthy feral cats. Within shelter and feral populations, no other effect of health status was found. The lower mean serum retinol and tocopherol concentrations in the feral and shelter cat groups could be due to oxidative or other forms of stress, the amount of vitamin consumed, or combinations of these. Further studies are needed to determine whether supplementation of fat-soluble vitamins improves the health status of feral or shelter cats. 相似文献
32.
To examine ovarian follicular response to low-dose injections of luteinizing hormone-releasing hormone (LHRH), 32 anovulatory, suckled beef cows were allotted to one of four treatment groups and injected with either saline or 500 ng LHRH every 2 h for 48 or 96 h, starting 21.4 +/- .4 d after parturition. Two hours after the last injection of LHRH, cows were ovariectomized and 10 to 15 ovarian follicles per pair of ovaries were removed and categorized by diameter as small (1.0 to 3.9 mm), medium (4.0 to 7.9 mm) or large (greater than or equal to 8.0 mm). Injections of LHRH did not affect (P greater than .10) steroid levels in small follicles or numbers of gonadotropin receptors in small and medium follicles. Concentrations of progesterone in fluid of medium follicles increased 1.5-fold (P less than .05) after 96 h of LHRH, whereas concentrations of estradiol and androstenedione were unchanged. In fluid of large follicles, concentrations of progesterone were fourfold greater (P less than .05) in LHRH-treated than in control cows at 48 h, but by 96 h progesterone was twofold greater (P less than .05) in control than LHRH-treated cows. In large follicles, concentrations of estradiol were unchanged (P greater than .10) after 48 h of LHRH injections but after 96 h estradiol was twofold greater (P less than .05) in LHRH-treated than control cows. Increased concentrations of estradiol in large follicles coincided with increased numbers of binding sites for human chorionic gonadotropin (hCG) but not follicle stimulating hormone (FSH) in granulosa and theca.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Nathalie C. Newby Cassandra B. Tucker David L. Pearl Stephen J. LeBlanc Ken E. Leslie Marina A.G. von Keyserlingk Todd F. Duffield 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(5):442-448
Post-operative pain management following rumen surgery is not common practice. We examined the effect of providing the pain medication ketoprofen to dairy cattle following the first stage of a rumen cannulation surgery, which involves an incision in the body wall and exteriorizing and clamping the rumen. The results of this study provide clear evidence that the first stage of the surgery was painful and ketoprofen at the time of and 24 h following surgery, alleviated some, but not all, of the post-surgical pain. Pain mitigation should be included when performing flank surgery in cattle. 相似文献
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36.
Oxygen transfer rate, power requirement and fuel consumption were determined for three paddlewheel aerators used for emergency aeration of channel catfish ponds. The power requirement of the tractor-powered units was directly related to the diameter of the paddlewheel drum and the paddle immersion depth. Oxygen transfer rates ranged from 6·9 to 41 kg h?1 and increased linearly with the power requirement. The largest paddlewheel aerator, operated at the maximum paddle depth, produced the highest oxygen transfer rate (41 kg h?1). Oxygen transfer efficiencies ranged from 1·29 to 1·97 kg kWh?1. 相似文献
37.
Craig S Tucker 《Aquaculture Research》2006,37(3):209-214
Silver carp Hypophthalmichthys molitrix (Valenciennes) were co‐cultured with channel catfish Ictalurus punctatus (Rafinesque) in 0.4 ha earthen ponds to determine the impacts of carp grazing on pond phytoplankton communities and cyanobacterial off‐flavours in catfish. Carp were stocked at densities of 0, 75, or 250 fish ha?1 in seven replicate ponds per treatment. The mean chlorophyll a concentrations (a measure of phytoplankton standing crop) steadily increased in all treatments from about 100 μg L?1 in April to more than 400 μg L?1 by mid‐October. Silver carp had no affect (P>0.1) on chlorophyll a concentrations across all sampling dates (April though October) or for sampling dates late in the growing season (August–October) when the prevalence of cyanobacterial off‐flavours among catfish populations is usually greatest. Silver carp did not eliminate odour‐producing cyanobacteria from pond phytoplankton communities: on sampling dates in September and October, three to six ponds in all treatments contained populations of the odour‐producing cyanobacteria Oscillatoria perornata, Anabaena spp., or both. Failure of silver carp to eliminate odour‐producing cyanobacteria resulted in a relatively high incidence in all treatments of ponds with off‐flavoured catfish. On sampling dates in September and October, catfish in three to five ponds in each treatment were tainted with either musty (2‐methylisoborneol) or earthy (geosmin) off‐flavours. The presence of silver carp had no obvious effect on off‐flavour intensity: on each sampling date, at least three ponds in each treatment contained catfish described as distinctly to extremely off‐flavored. Apparently, hypertrophic conditions in catfish ponds overwhelm the effect of silver carp grazing at the low carp densities used in this study. 相似文献
38.
39.
R P Radcliff K J Lookingland L T Chapin H A Tucker 《Domestic animal endocrinology》2001,21(3):187-196
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a hypothalamic neuropeptide that stimulates release of growth hormone (GH) from cultured bovine anterior pituitary gland cells, but the role of PACAP on the regulation of in vivo secretion of GH in cattle is not known. To test the hypothesis that PACAP induces secretion of GH in cattle, meal-fed Holstein steers were injected with incremental doses of PACAP (0, 0.1, 0.3, 1, 3, and 10 microg/kg BW) before feeding and concentrations of GH in serum were quantified. Compared with saline, injection of 3 and 10 microg PACAP/kg BW increased peak concentrations of GH in serum from 11.2 ng/ml to 23.7 and 21.8 ng/ml, respectively (P < 0.01). Peak concentrations of GH in serum were similar in steers injected with 3 or 10 microg PACAP/kg BW. Meal-fed Holstein steers were then injected with 3 microg/PACAP/kg BW either 1 hr before feeding or 1 hr after feeding to determine if PACAP-induced secretion of GH was suppressed after feeding. Feeding suppressed basal concentrations of GH in serum. Injection of PACAP before feeding induced greater peak concentrations of GH in serum (19.2 +/- 2.6 vs. 11.7 +/- 2.6 ng/ml) and area under the response curve (391 +/- 47 vs. 255 +/- 52 ng. ml(-1) min) than injection of PACAP after feeding, suggesting somatotropes become refractory to PACAP after feeding similar to that observed by us and others with growth hormone-releasing hormone (GHRH). We concluded that PACAP induces secretion of GH and could play a role in regulating endogenous secretion of GH in cattle, perhaps in concert with GHRH. 相似文献
40.
Folate Polyglutamylation is Required for Rice Seed Development 总被引:1,自引:0,他引:1