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Herrick GW 《Science (New York, N.Y.)》1928,68(1759):237-244
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1. White blood cell responses of broilers, turkeys and ducks were examined at regular intervals after being subjected to various degrees of food restriction. 2. Restricted-fed broilers showed increases in heterophil and basophil numbers, together with a corresponding decrease in lymphocytes. The heterophil/lymphocyte ratio was raised. There were no differences between broiler strains. 3. After only one week of feeding restricted diets, heterophils were significantly raised in selected and unselected 2-week-old ducks. At 21 weeks of age, those ducks receiving 50% of food required to achieve their ad libitum-fed body weight had raised heterophils. 4. Ducks receiving food to achieve 25% of ad libitum-fed birds produced a marked basophilia, but no heterophilia. 5. After two weeks of food restriction, turkeys responded with significant heterophil/lymphocyte ratios following two degrees of restricted feeding. 6. It was concluded that in some poultry, a heterophilia may be the response to mild to moderate stress but a basophilia may result after severely stressing birds. 相似文献
16.
Estrogen and progesterone receptor status of mammary carcinomas and correlation with clinical outcome in dogs. 总被引:3,自引:0,他引:3
E A Sartin S Barnes R P Kwapien L G Wolfe 《American journal of veterinary research》1992,53(11):2196-2200
Estrogen and progesterone receptors (ER, PR) were measured in cytosol fractions from 18 primary canine mammary carcinomas by use of biochemical assays. One or both receptors were detected (> 10 fmol/mg of cytosol protein) in 11 tumors: 5 ER and PR; 2 ER only; 4 PR only. Mean cytoplasmic receptor concentrations (fmol/mg of cytosol protein) were 22.8 +/- 2.9 (SEM) for ER and 51.0 +/- 10.3 for PR in tumors containing ER and PR, 28.8 +/- 12.1 for ER in tumors containing only ER and 13.2 +/- 1.5 for PR in tumors containing only PR. Estrogen or progesterone receptors or both were identified in 6 of 9 tubular adenocarcinomas, 4 of 5 papillary adenocarcinomas, and 1 of 1 squamous cell carcinoma. These receptors were not identified in solid carcinomas (n = 2) or a single spindle cell carcinoma. Although the number of cases was limited, survival times of dogs tended to be longest in those with tumors containing ER alone or in combination with PR, intermediate in those with tumors containing only PR, and shortest in those with tumors without ER or PR. A correlation was not apparent between receptor status and age, presence of ovaries, tumor size, or histologic classification of the tumor. In the analysis of this series, the extent of surgery (mastectomy of the involved gland vs unilateral or bilateral mastectomy) did not appear to influence the outcome of the disease, and metastasis to regional lymph nodes did not appear to be a reliable prognostic indicator. 相似文献
17.
A S Waldvogel G A Anderson D L Phillips B I Osburn 《Comparative immunology, microbiology and infectious diseases》1992,15(1):53-63
Bluetongue virus infection in sheep and cattle during fetal development causes neuropathology. Two strains of bluetongue virus serotype 11 designated as UC-2 and UC-8 have different virulence patterns in newborn mice. These viruses have distinctly different electropherotype patterns on polyacrylamide gel electrophoresis indicating a genetic difference in these two viruses of the same serotype. Four bovine fetuses each were inoculated intramuscularly with either UC-2 or UC-8, and one fetus was inoculated with placebo. The inoculation was made intramuscularly through the uterine wall at 120 days' gestation, and the bovine fetuses were recovered by cesarean section 12 or 20 days after inoculation. Fetal blood was collected for virus isolation and serology. Virus was reisolated from brain, blood, lung and liver. Both strains, UC-2 and UC-8, cause severe lesions in the 120 day fetuses. The encephalomalacic lesions occurred earlier and were more severe in fetuses inoculated with UC-8 as compared to those inoculated with UC-2. The subtle differences observed in the fetuses inoculated with the two different strains suggest that there is a difference in pathogenic potential of the two viruses. These differences do not appear to be completely dependent upon the host species. 相似文献
18.
Michael J. A. Young Arlo W. Fast Paul G. Olin 《Journal of the World Aquaculture Society》1989,20(1):7-11
Chinese catfish ( Clarias fuscus ) were successfully spawned in Hawaii using human chorionic gonadotropin (HCG) at dosage rates of two and four international units (IU) per gram body weight. Fish not injected with HCG did not produce viable eggs. Successful spawns with HCG occurred between May and October. Hatch rates of up to 80% were obtained during June, July, and August for those fish given either a 2 or 4 IU per gram body weight injection of HCG. Fish spawned in either May or October yielded significantly higher hatch rates when injected with 4 rather than 2 IU per gram body weight. Fish held at elevated temperatures (28 to 30 C) prior to the normal spawning season developed significantly larger oocyte diameters, 60 days earlier than fish held under ambient temperature conditions (21.5 to 24 C). Photoperiod manipulation at ambient temperature conditions was associated with earlier oocyte maturation, but photoperiod effects were much less important than temperature. 相似文献
19.
G W De Lisle D M Collins H F Huchzermeyer 《The Onderstepoort journal of veterinary research》1992,59(2):163-165
Restriction endonuclease analysis and DNA hybridization revealed five ovine strains of Mycobacterium paratuberculosis from South Africa had identical DNA patterns to an ovine strain from Canada. Genetically this strain type has features in common with the two major groups of M. paratuberculosis. 相似文献
20.
G. Power 《Ecology of Freshwater Fish》1992,1(1):12-25
Abstract– Juvenile chinook salmon in the Waitaki River, New Zealand and demonstration channels, living at about 16°C, increased in length by 0.32 mm day−1 between 4 November and 4 March. They gained weight quickly, accumulated large visceral fat deposits and had high conditions factors. At 1600 h, stomachs averaged half full. The number of prey tended to decline as the fish grew and consumed larger items. Initially the diet was based mainly on chironomid larvae, but by December it included a diversity of prey in more equal proportions. These included Deleatidium in the Waitaki; amphipods in the demonstration channels; various trichopterans, hemipterans, elmid beetles, zooplankton. terrestrial dipterans and a variety of other prey. There were significant differences between sites in numbers of prey consumed and these probably reflected differences in the benthos. Diets in the Waitaki differ from those in the Rakaia River and the food of juvenile salmon appears closely linked to the availability of a diverse range of possible prey. 相似文献