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271.
272.
Salmonella enterica serovar enteritidis burden in broiler breeder chicks genetically associated with vaccine antibody response 总被引:3,自引:0,他引:3
The relationship between antibody response to Salmonella enteritidis vaccine and internal organ burden of S. enteritidis is not fully understood. The genetic relationship, therefore, between postchallenge S. enteritidis burden and antibody response to S. enteritidis vaccine was determined in broiler breeder chicks. Sibling chicks from a broiler breeder male line were either inoculated with a pathogenic S. enteritidis or vaccinated with a commercial S. enteritidis vaccine. Spleen, liver, cecal wall, and cecal content samples from S. enteritidis-challenged chicks (n = 120) were cultured for enumeration of bacteria. Unchallenged chicks (n = 314) were vaccinated at 11 days of age, and serum samples were taken at 10 days postvaccination. Antibody response to vaccination and number of S. enteritidis in cecal content cultures were negatively correlated (-0.772), demonstrating that genetic potential for greater antibody response to S. enteritidis vaccine is associated with lesser S. enteritidis bacterial burden in cecal content of broiler breeder chicks. The findings suggest that genetic selection for vaccine antibody responsiveness can lower bacterial burden in the gut lumenal content and, thus, potentially reduce contamination of poultry products at processing. 相似文献
273.
274.
Differential induction of superoxide dismutase in downy mildew-resistant and -susceptible genotypes of pearl millet 总被引:9,自引:0,他引:9
Differential induction of superoxide dismutase (SOD) in downy mildew-resistant and -susceptible genotypes of pearl millet ( Pennisetum glaucum ) was observed on inoculation with Sclerospora graminicola . SOD activity was studied in resistant (IP18292) and susceptible (23B) pearl millet seedlings inoculated with S. graminicola . SOD activity increased by 2·3-fold in resistant seedlings upon inoculation. SOD activity was greatest in roots, with a specific activity of 3182 U per mg protein, after inoculation. SOD activity increased in all the resistant genotypes upon inoculation with S. graminicola . Native PAGE analysis showed four isozymes of SOD, three of which (SOD-1, -2 and -4) were Cu/Zn-SOD, whereas isozyme SOD-3 was Mn-SOD. This study also revealed increased intensity of all four isozymes of SOD in the resistant genotype upon inoculation. The involvement of SOD in pearl millet (host)–downy mildew pathogen interaction is discussed. 相似文献
275.
Ultrastructural Studies of conidiogenesis ofAscochyta rabiei, the causal Organism of chickpea blight
Studies employing transmission (TEM) and scanning (SEM) electron microscopy revealed that conidiogenous cells of the chickpea blight fungus,Ascochyta rabiei (Pass.) Labr., resembled phialides in most of their features. The phialides were generally of a simple type, but occasionally they proliferated in a percurrent fashion. There is enough evidence to suggest that the fungus is better placed in genusPhoma. SEM has been employed for the first time to study internal details of fructifications of a closed type in coelomycete fungi. 相似文献
276.
277.
Rama Rao S. V. Prakash B. Rajkumar U. Raju M. V. L. N. Srilatha T. Reddy E. P. K. 《Tropical animal health and production》2018,50(5):1147-1154
Tropical Animal Health and Production - An experiment was conducted to study the effects of supplementing sprouts of pulses on performance, carcass variables, immune responses, and anti-oxidant... 相似文献
278.
Sarkar M Chakraborty P Sharma BC Deka BC Duttaborah BK Mohanty TK Prakash BS 《Research in veterinary science》2008,85(2):233-237
Plasma progesterone profiles were used to assess superovulatory responses in cyclic yaks (n=10) in terms of the number of ovulations and the number of embryos recovered. The animals were synchronized into oestrus following Ovsynch treatment. All the animals received a total of 200 mg Folltropin divided into morning and evening and spread over 4 days, beginning on day 10 of the oestrus cycle (day of expected oestrus=day 0). Plasma samples for progesterone estimation were collected daily starting from the day of expected synchronized oestrus to the day of flushing. All the animals were palpated per rectum on the day of flushing in order to record the number of corpora lutea. Of an estimated 27 ovulations from the nine yaks, only 16 embryos were recovered. Plasma progesterone profiles from individual yaks suggested that a poor superovulatory response in terms of embryo recovery in some animals was caused by the lysis of corpora lutea before flushing which was carried out 7 days after superovulatory oestrus. It was suggested that flushing 5 days post superovulatory oestrus could improve the superovulatory response in this species. 相似文献
279.
M. Sarkar U.A. Nandankar B.K. Duttaborah S. Das M. Bhattacharya B.S. Prakash 《Livestock Science》2008,115(2-3):313-318
The role of growth hormone (GH) in postnatal growth is well established. Its basal level and relation to growth performance in different age group yaks has not been characterized until now. To estimate the normal blood GH level in yaks, a total of eighty five female yaks were divided in to thirteen age groups. BW of all animals was recorded on two consecutive days per week and average of weekly BW was considered for growth rate calculation. Blood samples collected twice weekly for four consecutive weeks were assayed for GH by a direct, simple and highly sensitive enzyme immunoassay (EIA) on microtitre plates using the biotin–streptavidin amplification system and the second antibody coating technique developed for the first time in this species. The EIA was carried out directly in 100 μL of yak plasma. The sensitivity of EIA procedure was 20 pg/well GH, which corresponds to 0.2 ng/mL plasma For the biological validation of assay, 2 mature yaks were administered (10 μg, iv) with a synthetic analogue of GHRH and blood samples were collected at 15-min interval using indwelling jugular catheter beginning 2 h prior to GHRH injection till 8 h thereafter. In both the animals, sharp increases in GH concentrations were recorded 75 min post GHRH administration, which confirms the biological validation of the EIA. It was found that mean GH among the age groups differ (p < 0.05). With increasing age and BW, GH level decreased. The age groups with higher plasma GH showed higher growth rates (r = 0.73). In conclusion, a highly sensitive enzymeimmunoassay procedure has been developed for the first time to determine plasma GH levels in bovine (yak) plasma. A close relationship of plasma GH concentration with age, BW and growth rates was found in yaks. 相似文献
280.
Now, it is well known that in bovines HDL-C act as substrate for ovarian steroidogenesis. The restriction of entry of other lipoprotein parameters is due to ovarian blood barrier, which restricts the entry of other lipoproteins, which are bigger in size. In vitro studies have indicated their role in mediating proliferation of cells. Besides gonadotropin, Growth Hormone (GH) is also gaining importance in the field of reproduction. GH receptors have been localized on the ovaries and follicle of bovines. Further it has been suggested that it can be the direct role of the hormone or it can be mediated through IGF-I. It has been assigned various roles in mediating follicle development, ovulation and corpus luteum maintenance. The river buffaloes are capable of breeding throughout the year, but during certain period of time were found to be more favourable than the others. It has been found that, winter season and hot humid season exhibit two extreme conditions of temperature variation; Hot humid season being unfavourable than the winter season because of high humidity and reasonably high temperature. It has been observed that during June to August months, conception rate and exhibition of estrus behaviour is low. This study was undertaken to analyze different lipoprotein cholesterol parameters namely Total cholesterol (TC), High-density lipoprotein cholesterol (HDL-C), Triglycerides (TG) and Low density lipoprotein cholesterol (LDL-C) in the plasma of cyclic Murrah buffaloes throughout the estrous cycle. The mean plasma concentration (μg/ml) of different lipoproteins during hot humid season were TC 592 ± 40, HDL-C 229 ± 42, TG 345 ± 95, LDL-C 285 ± 94.Where as in winter season their concentrations were 1381.0 ± 31.0, 1793.0 ± 110.0, 511.0 ± 21.0, 608.0 ± 94.0 respectively.
The mean ± SEM circulatory level of GH was low during HH season than during winter (6 ± 2 ng/ml vs. 17 ± 2 ng/ml). During estrous cycle only one peak of GH was exhibited during hot humid season where as three peaks were exhibited during winter season. It can be concluded that winter season is favourable for maintaining physiological levels of hormones and metabolic parameters, which in turn may increase the reproductive efficiency of bovines. During winter season average temperature was 15 ±5 °C. During hot humid season average temperature was 34 ± 3 °C. THI was more than 75%. 相似文献