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31.
The objective of this study was to analyse the effects of different levels of rumen-degradable protein (RDP) on intake, digestibility and microbial protein synthesis by supplementing mustard oil cake (MOC) on rice straw-based diet of cattle (Bos indicus) in Bangladesh. A 4 × 4 Latin square design was applied. Four diets having constant energy (7.0 MJ/kg of dry matter (DM)) with varying levels of RDP (M 0 = 4.1 g/MJ (control), M 1 = 6.3 g/MJ, M 2 = 8.3 g/MJ and M 3 = 12.4 g/MJ of metabolizable energy (ME)) were received by each animal for a period of 28 days. A metabolism trial was conducted for 7 days. Results indicate that with increasing levels of RDP, crude protein (CP) and RDP intake increased significantly (P < 0.01). The significant (P < 0.01) increase in digestibility values are obtained for DM, organic matter, CP and digestible organic matter in the rumen. The digestibility of neutral detergent fibre and acid detergent fibre was also increased significantly (P < 0.05). The total nitrogen (N), ammonia-N and total volatile fatty acids increase significantly (P < 0.01) while the rumen pH increased from M 0 to M 2 and decreased thereafter. The efficiency microbial N intake increased significantly (P < 0.01) but showed a curvilinear response with higher RDP level (12.40 g/RDP/MJ ME). This study concludes that supplementation of RDP from MOC enhances the intake, digestibility and microbial protein synthesis which ultimately increases utilization of low-quality feed resources that can be used for developing cost-effective feeding systems on a straw-based diet in tropical regions.  相似文献   
32.
Twenty-four 10- to 16-week-old calves in a dairy herd in Birjand, Iran, inadvertently received an excessive dose of salinomycin mixed with barley grain. There was 58% mortality within 10 d. The calves had high serum AST, LDH, and CK activities; histopathologic lesions in myocardium, liver, and kidneys; and clinical signs associated with acute and congestive heart failure.  相似文献   
33.
Ovar-DRB1 is one of the most important response genes in the major histocompatibility complex (MHC) class II region of sheep. Gene polymorphism in the second exon of Ovar-DRB1 in three different Iranian fat-tailed sheep breeds (Lori-Bakhtiari, Shaul and Zandi) was analyzed by either restriction fragment length polymorphisms (RFLP) or direct sequencing. A total of 92 Lori-Bakhtiari, 40 Shaul, and 47 Zandi sheep were examined. PCR-RFLP identified 17 genotypes in Lori-Bakhtiari sheep, 12 in Shaul sheep and 11 in Zandi sheep. Collectively, 24 different genotypes could be found for Iranian fat-tailed sheep. Using direct sequencing, seven new sequences in exon 2 of the Ovar-DRB1 gene were identified. Generalized linear modeling with a multinomial error structure showed that the sheep populations had significantly different allele frequencies.  相似文献   
34.
Bovine isoleucyl-tRNA synthetase (IARS) disorder, a major cause of weak calf syndrome, is caused by a homozygous missense (c.235G>C) mutation in the bovine IARS gene of Japanese Black (JB) cattle, which was identified in 2013. However, the extent to which the carrier rate has changed at Kagoshima prefecture, Japan, and whether the carrier status is associated with any clinical or reproductive problems, have yet to be ascertained. In this study, using a real-time polymerase chain reaction-based genotyping assay, we determined the carrier rate in a regional JB cow population at Kagoshima prefecture. Comparative analyses were performed on the metabolic profile test (MPT) results and reproductive performance data obtained for heterozygous carrier and homozygous wild-type cows. In 2009 and 2018, DNA samples were collected from 130 and 462 clinically healthy JB cows, respectively, in Kagoshima prefecture. MPT results and reproductive performance data were evaluated for 62 cows, comprising four heterozygous carriers and 58 wild-type cows. Genotyping revealed that the carrier rate was 6.9% in 2009 and 1.5% in 2018, the difference of which was statistically significant (P<0.005). There were no statistically significant differences between the carrier and wild-type cows with respect to either MPT results or reproductive performance, indicating that the carrier cows have necessary IARS activity to maintain minimal health and reproductive potential.  相似文献   
35.
The use of morphine has been demonstrated to increase susceptibility to infections. Herpes simplex virus type 1 (HSV-1) is a highly successful pathogen among immunocompromised individuals. In the present study, due to the importance of HSV vaccination in morphine abusers, the effects of chronic morphine exposure on the host response to a HSV-1 gB DNA-based vaccine have been investigated. The study is addressing an important aspect of vaccine development among the susceptible (immunocompromised) hosts. BALB/c mice were exposed to morphine over 11 days. They were then vaccinated with DNA vaccine or KOS strain as a live vaccine. The findings showed that the morphine-treated animals failed to respond to DNA vaccination evaluated by the anti-HSV gB antibody titer, delayed type hypersensitivity (DTH) and lethal HSV-1 challenge. Under the same conditions, the KOS vaccine showed a reduced Ab titer and DTH response in morphine-treated mice, but could protect mice against the lethal challenge and was safe for vaccination of morphine-treated animals.  相似文献   
36.
Antibiotic resistance and ESBL constitute a risk to human and animal health. Birds residing close to humans could mirror the spectrum of human associated antibiotic resistance. Household pigeons were screened in Bangladesh to shed light on human associated, as well as, environmental antibiotic resistance. Escherichia coli from pigeons (n = 150) were tested against 11 antibiotics. 89% E. coli isolates were resistant to one or more critically important human antibiotics like ampicillin, cefadroxil, mecillinam, ciprofloxacin, gentamicin and tigecycline. No carbapenamase-producers were detected and the lower ESBL prevalence (5%) in pigeons. ESBL-producing E. coli isolates had blaCTX-M-15 genes. Pigeons shared some bacterial clones and had bird associated sequence types like E. coli ST1408. Fecal carriage of bacteria resistance of critically important human antibiotics, together with examples of shared genotypes among pigeons, indicate the human-birds and bird to bird transmissions are important in the epidemiology of antibiotic resistance.  相似文献   
37.
ObjectivesTo study the effect of pregnancy and lactation on echocardiographic parameters in Holstein dairy cows.AnimalsNine multiparous high milk producing (HMP) dairy cows (producing more than 40 kg of milk per day in peak production) and 9 low milk producing (LMP) cows (producing less than 30 kg or milk per day in peak production).MethodsEchocardiography was performed twice; one month before calving and two months after calving.ResultsThe heart rate of HMP cows in the early lactation period was significantly higher than in the dry period. In LMP cows, there was a significant increase in left ventricular dimension in the early lactation period as compared to the dry period, and the interventricular septum in systole (IVSs) in the dry period was significantly thicker than early lactation period. In HMP cows, there was an increase in the right ventricular diameter in systole in the early lactation period as compared to the dry period. Left ventricular and aortic dimensions in the dry period of HMP were significantly higher than those of LMP cows. When the data were corrected for body weight, comparison of values of the dry period of HMP and LMP cows showed that left ventricular volume in systole in HMP was significantly higher and that IVSs, left ventricular fractional shortening and ejection fraction were significantly lower than in LMP cows.ConclusionsThis study demonstrated that lactation influences the intracardiac dimensions. The amount of milk production can influence echocardiographic parameters in dairy cows.  相似文献   
38.
The isolation and NMR spectra of otosenine (1) and seneciphylline (2) from Senecio lorenthii are reported.  相似文献   
39.
2002年1月至6月对孟加拉涝原地区两个不同的宗教部落(印度教和穆斯林教)的传统家园森林进行了探索性研究,包括印度教和穆斯林教社团对树种(乔木和灌木)的偏爱度、类似性、造林材料及来源、植树地点和间距。研究发现Mangifera indica作为乔木树种,Ocimum sanctum作为灌木树种为印度教社团最喜爱的树种;Artocarpus heterophyllus和Lawsonia inermis分别为穆斯林社团最喜爱乔木树种和灌木树种。两中不同宗教社团选择乔木数种的相同性为86.57%,灌木树种为78.48%。两个宗教部落使用种子和苗木作为造林材料最多。乔木树种的造林材料主要来自家园(39%)灌木树种主要来自自然界(40%)。表3参27。  相似文献   
40.
采用多级采样的方法研究了孟加拉国农村耕作区内棕榈树的传统利用模式和当地的管理经验。农民管理棕榈主要为获取树液产品,生产以糖为主的次生品。树液可直接用作饮料,也可加工成糖蜜或酒精饮料。7块不同地块为棕榈提供生长环境,20.40%的棕榈种植在果园内。尽管中等级的农民拥有多数棕榈(33%),但是主要管理棕榈的是没有土地的农民,他们靠棕榈维持生计。这些农民将自己的智慧应用到棕榈管理当中,从种植到开孔取树液再到产品加工。如果能更科学地管理棕榈,加上农民的智慧,棕榈业将会对当地经济发展起到重要作用,也会丰富当地生物多样性。  相似文献   
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