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141.
Magorzata Pomorska‐Ml Krzysztof Kwit Ewelina Czyewska‐Dors Zygmunt Pejsak 《Journal of veterinary pharmacology and therapeutics》2019,42(3):318-323
The effect of a standard, single dose therapy with tulathromycin was investigated on the postvaccinal humoral and cellular immune response in pigs vaccinated against swine influenza. Forty‐five pigs, divided into 3 groups, were used (control not vaccinated (C, n = 15), control vaccinated (CV, n = 15), and experimentally received tulathromycin (TUL, n = 15)). For vaccination of pigs, an inactivated, commercial vaccine was used. Pigs from TUL group received single dose of tulathromycin intramuscularly, at the recommended dose (2.5 mg/kg body weight). Pigs from TUL and CV groups were vaccinated at 8 and 10 weeks of age. The specific humoral and cellular immune response against swine influenza virus (SIV) was evaluated. The results of present study showed that humoral postvaccinal response after vaccination against SIV can be modulated by treatment with tulathromycin. In pigs from TUL group, the significantly higher titers of anti‐SIV‐specific antibodies were observed 4 and 6 weeks after booster dose of vaccine. Simultaneously, T‐cell‐mediated immune response against SIV was not affected by tulathromycin. Our recent study confirmed the importance of defining the modulatory activity of tulathromycin because of its influence on the immune response to vaccines. Since the antibodies against hemagglutinin are crucial for the protection against SIV, the present observations should prompt further studies on the practical significance of recent results in terms of clinical implications (postvaccinal protection) in the field conditions. 相似文献
142.
鲁西牛的染色体研究 总被引:1,自引:0,他引:1
研究了40头鲁西牛(♂37,♀3,2n=60)染色体的 G 带,R 带,C 带及Ag-NOR,着重分析了 y 染色体的形态及带型。在常规 Giemsa 染色的分裂相上,y染色体和小的常染色体形态相近。经常规—C 带连续染色,准确识别出 y 染色体之后测量了18条 y 染色体,臂比为3.19,属亚端着丝点染色体。y 染色体的着丝点区和短臂与常染色体的着丝点区和短臂在 G 带、C 带的带型上差别很大,表明构成它们 DNA的硷基成份有差别。统计的152个细胞的 Ag-NOR 中,平均每细胞 Ag-NOR 数为5.81±1.38,变化范围2—9。按染色体长度排列,NOR 位于2、3、4、11、22(或21)和28号常染色体末端。第22(或21)号染色体上存在 NOR 在其它牛种上尚未有过报道。 相似文献
143.
豆科牧草追施钾肥试验 总被引:5,自引:0,他引:5
试验结果表明,当旱地红壤养分中的速效钾含量在75.5ppm情况下,白三叶每公顷追施氯化钾225kg,结果施肥比对照每公顷增产鲜草7779kg,每公顷氯化立鲜草34.6kg,增产率达29%。按生物统计t测验,增产显著。当稻田速效钾含量在45ppm条件下,给紫云英每公顷施用氯化钾112.5kg,结果施肥比对照每公顷增产鲜草5000-7750kg,平均每公顷增产6750kg。每公斤钾肥可增产粮食23.5 相似文献
144.
Jianning He Qiuyue Liu Shunyu Yu Mengyuan Lei Jifeng Liu Ran Di Zhaojia Ge Wenping Hu Xiangyu Wang Nan Liu Mingxing Chu 《Reproduction in domestic animals》2021,56(3):427-436
Follistatin-like 3 (FSTL3) is a regulator of cellular apoptosis and was previously identified via RNA-Seq to be associated with follicular development in mammalian ovaries. However, the mechanism underlying the FSTL3 regulation of oestrus in sheep remained poorly understood. In this study, the oestrogen (E2) and progesterone (P4) concentrations in blood were detected, and the expression level and functional analysis of FSTL3 in the ovary were studied during the different reproductive stage in Aohan fine wool sheep (seasonal breeding breed in China). The concentrations of E2 and P4 at the anestrus were significantly lower compared to dioestrus, proestrus and oestrus stages. Higher expression levels of FSTL3 were observed in the sheep ovary, hypothalamus, and thyroid. During different reproductive stages, higher expression levels were found during the stages of dioestrus and proestrus, while lower levels were found during the oestrus and anestrus stages. Functional analysis of FSTL3 was performed in primary granulosa cells (GCs) of sheep. The concentration of E2 increased significantly after RNAi interference of FSTL3, while the P4 level decreased. FSTL3 can decrease P4 levels, which might be involved in mediating oestrous cycle in sheep. 相似文献
145.
146.
Yu-Xiong Lai Bao-Lei Jin Yu Xu Li-jie Huang Run-Qing Huang Yong Zhang Jimmy Kwang Jian-Guo He Jun-Feng Xie 《Veterinary immunology and immunopathology》2014,157(1-2):87-96
Betanodaviruses are the causative agents of viral nervous necrosis (VNN), a serious disease of cultured marine fish worldwide. Virus-like particles (VLPs) are one of the good novel vaccine candidates to control this disease. Until now, betanodavirus vaccine studies mainly focused on the humoral immune response and mortality after virus challenge. However, little is known about the activation of genes responsible for cellular and innate immunity by vaccines. In the present study, VLPs of orange-spotted grouper nervous necrosis virus (OGNNV) were produced in prokaryotes and their ability to enter Asian sea bass cells was the same as native virus, suggesting that they possess a similar structure to OGNNV. VLPs immunogenicity was then determined by intramuscularly vaccinating Epinephelus coioides at different concentrations (1.5 or 15 μg g?1 fish body weight, FBW) and immunizing frequencies (administration once, twice and thrice). A single vaccination with the dosage of 1.5 μg g?1 FBW is enough to provoke high titer antibodies (average 3 fold higher than that of negative control) with strong neutralizing antibody titer as early as 1 week post immunization. Furthermore, quantitative PCR analysis revealed that eleven genes associated with humoral, cellular and innate immunities were up-regulated in the liver, spleen and head kidney at 12 h post immunization, correlating with the early antibody response. In conclusion, we demonstrated that VLP vaccination induced humoral immune responses and activated genes associated with cellular and innate immunity against betanodavirus infection in orange-spotted grouper. 相似文献
147.
Z. P. Yu M. Xu K. Liu J. H. Yao H. X. Yu F. Wang 《Journal of animal physiology and animal nutrition》2014,98(1):169-177
Four goats (30.1 ± 1.3 kg) with common bile duct re‐entrant catheter and duodenal catheter were used to evaluate the effects of duodenal leucine infusion on pancreatic exocrine secretion and plasma parameters with two 4 × 4 Latin square design experiments. In the long‐term infusion experiment, goats were fed twice daily [700 g/day, dry matter (DM) basis] at 8:00 and 18:00 hours and were duodenally infused with 0, 3, 6, 9 g/day leucine for 14 days. Pancreatic juice and jugular blood samples were collected over 1‐h intervals for 6 h daily from d 11 to 14 days to encompass a 24‐h day. In the short‐term experiment, goats were infused leucine for 10 h continuously at the same infusion rate with Experiment 1 after feed deprivation for 24 h repeated every 10 days. Pancreatic juice and blood samples were collected at 0, 1, 2, 4, 6, 8 and 10 h of infusion. The results showed that the long‐term leucine infusion did not affect pancreatic juice secretion, protein output, trypsin and lipase secretion and plasma insulin concentration, but linearly increased α‐amylase secretion. No changes in pancreatic protein and lipase secretion were observed in the short‐term infusion. Pancreatic juice and α‐amylase secretion responded quadratically, with the greatest values observed in the 3 and 6 g/day leucine respectively. Trypsin secretion linearly decreased, while plasma insulin concentration increased linearly with increased leucine infusion. The results demonstrated that duodenal leucine infusion dose and time dependently regulated pancreatic enzyme secretion not associated with the change in plasma insulin concentration. 相似文献
148.
149.
Identification of lactic acid bacteria in the feces of dairy cows fed whole crop maize silage to assess the survival of silage bacteria in the gut 下载免费PDF全文
Hongyan Han Chao Wang Yanbing Li Zhu Yu Qingfang Xu Guangpeng Li Tang Thuy Minh Naoki Nishino 《Animal Science Journal》2018,89(1):97-104
In order to assess the survival of lactic acid bacteria (LAB) in whole crop maize silage in the gut of dairy cows, one representative silage sample and three different feces samples were collected from dairy cows on three dairy farms in Hua Bei, China and three dairy farms in Kyushu, Japan. The composition of the bacterial community was examined by denaturing gradient gel electrophoresis and quantitative polymerase chain reaction. Lactobacillus acetotolerans was detected in all bunker‐made maize silage samples, regardless of the dairy farm or sampling region from which they were sourced. A total of eight LAB species were detected in the maize silage samples, of which three (L. acetotolerans, L. pontis and L. casei) appeared to survive digestion. The populations of L. acetotolerans in silage and feces were 106–7 and 103–4 copies/g, respectively, indicating that, even for the LAB species showing potential survival in the gut, competition in this niche may be harsh and the population may substantially decrease during the digestion process. It may be difficult for silage LAB to survive in the gut of silage‐fed dairy cows, because marked decrease in population can take place during the digestion process, even for surviving species. 相似文献
150.