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91.
Tropical Animal Health and Production - Broiler meat is the largest and cheapest protein source in Malaysia. Using the policy analysis matrix (PAM), this study examines the comparative advantage of...  相似文献   
92.
The immunohistochemical expression of topoisomerase IIbeta binding protein 1 (TopBP1) was examined in 123 feline mammary lesions (18 non-neoplastic lesions including six fibroadenomatous hyperplasia and 12 duct ectasia, 17 adenomas and 88 carcinomas) in relation to histological grade, oestrogen receptor alpha (ERalpha) status, proliferation index (Ki67) and p53 expression. There was positive staining for TopBP1 in 122 of 123 feline mammary lesions, although nine samples had fewer than 20% positive cells. The percentage of cells positive for TopBP1 increased with histological grade. Most staining was nuclear but both nuclear and cytoplasmic staining was observed as the degree of malignancy increased. TopBP1 is expressed in feline mammary tumours and its expression is correlated with histological grade. Many neoplasms which over-express p53 or are ERalpha negative show TopBP1 immunoreactivity.  相似文献   
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94.
The performance of a fluorescence polarization assay (FPA) that detects antibodies to Mycobacterium bovis in bovine sera is described. The FPA reported here is a direct binding primary screening assay using a small polypeptide derived from the M. bovis MPB70 protein. A secondary inhibition assay confirms suspect or presumed positive samples. Specificity studies involved five different veterinary laboratories testing 4461 presumed negative bovine samples. FPA specificity was 99.9%. The FPA was used to identify herd status as either M. bovis infected or non-infected. Herd surveillance studies (nine herds) were performed in Mexico and South Africa. The FPA had a specificity of 100% (two negative herds), and correctly identified six of seven infected herds. Finally, sera from 105 slaughter animals that had gross lesions in lymph nodes similar to those seen with bovine tuberculosis were tested by the FPA. Thin sections from the associated formalin-fixed paraffin-embedded samples of lymph nodes were stained using hematoxylin and eosin (H&E) for morphologic examination and using the Ziehl-Neelsen (ZN) method for detection of acid-fast bacilli. Of the 105 animals, 78 were classified as TB suspect based on lesion morphology, 21 were positive by ZN, 9 were positive by FPA and 13 were positive by PCR for the tuberculosis group of Mycobacterium. Among the 21 ZN positives, 11 (52.4%) were PCR positive. Among the 9 FPA positives, 8 (88.9%) were PCR positive. For the 13 PCR positives, 8 (61.5%) were FPA positive and 11 (84.6%) were ZN positives. These results show that use of the FPA for detection of M. bovis infection of cattle has value for bovine disease surveillance programs.  相似文献   
95.
Convolvulus arvensis is a toxic allelopathic weed that suppresses germination and growth of crops.The prime object of present study was to investigate effect of Convolvulus arvensis water extract on germination and performance of okra with different seed sizes.The seeds of okra variety pusa green were separated into three different sizes,viz large size(4.00-5.00 mm),medium size(3.00-3.50 mm)and small size(2.00-3.50 mm),and then soaked in allelopathic plant bindweed water extract and kept in patrisdishes for germination into the germinator at 15℃.The experiment was laid out using Complete Randomized Design(CRD)with three replications.The results showed that after sowing of 12 days the highest germination was observed in non-treated seeds as compared to seeds treated in Convolvulus arvensis water extract for 1 h,further non-treated large seeds produced maximum plants as compared to treated small seeds after sowing of 24 days.Meanwhile,root length,shoot length,root fresh and dry weight,shoot fresh and dry weight were recorded higher in non-treated large seeds as compared to small seeds soaked for 1 h in Convolvulus arvensis allelopthic water extract.It could be found that Convolvulus arvensis affected germination,seed growth and overall performance of okra,further presence Convolvulus arvensis in crops could cause negative impact on germination and integrity of okra crops.  相似文献   
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97.
Detection of infected poultry flocks is essential for controlling eggborne transmission of Salmonella enteritidis to humans. The present study evaluated the detection of antibodies in the sera of experimentally infected chickens by a fluorescence polarization assay with a tracer prepared from the O-polysaccharide of S. enteritidis and an enzyme-linked immunosorbent assay (ELISA) with an S. enteritidis flagellin antigen. In two trials, groups of specific-pathogen-free laying hens were infected orally with either 10(6) or 10(8) colony-forming units (CFU) of S. enteritidis (phage type 13a) or with 10(8) CFU of Salmonella typhimurium. Serum samples were collected before inoculation and at five subsequent weekly intervals. Both assays successfully detected the majority of hens infected with S. enteritidis at either dose level, but they also identified a substantial number of hens infected with S. typhimurium as seropositive. The fluorescence polarization test detected S. enteritidis infection significantly more often and cross-reacted with sera from hens infected with S. typhimurium significantly less often than the ELISA. The fluorescence polarization assay also offered advantages in terms of speed and methodologic simplicity.  相似文献   
98.
The aim of the study was to determine optimum dietary energy level during the last trimester of pregnancy for Sahiwal heifers in subtropical Pakistan. Sixteen Sahiwal heifers, 5–6 months pregnant, were assigned to four dietary treatments with four heifers on each treatment. Isonitrogenous (CP = 14.1%) diets having varying energy, namely, ME 88%, ME 100% (Control), ME 112% and ME 124% of NRC recommended level for pregnant heifers, were fed until calving. All were fed a similar diet after calving. Precalving weight gain was highest (P < 0.05) in heifers fed ME 112 and 124% (486 ± 13 and 497 ± 5 g/day, respectively) followed by ME 100% (444 ± 7 g/day), and the lowest weight gain was recorded for ME 88% (397 ± 8 g/day). A similar trend was observed for feed efficiency. Body condition score at calving in groups ME 124% and ME 112% was higher than ME 88% and ME 100%. Nutrient digestibility, birth weight of calves and milk composition except fat content were not influenced by energy levels. The highest daily milk yield was observed in heifers fed ME 100% followed by ME 112, 124, and 88%. We conclude that the NRC recommendation is applicable to the subtropical region.  相似文献   
99.
新疆杏品种(系)遗传多样性分析及DNA指纹图谱库构建   总被引:2,自引:0,他引:2  
【目的】从ISSR分子标记水平分析新疆主栽杏品种(系)的遗传多样性和亲缘关系,构建新疆杏品种(系)的DNA指纹图谱数据库,为杂交育种、品种鉴定和品种分类提供理论依据。【方法】从供试样品中选取表型差异较大的6份材料对100个ISSR引物进行筛选,最终筛选出条带清晰、主带明显、多态性丰富、能够稳定重复且对品种具有较高鉴别力的ISSR特征引物,对48个新疆杏品种(系)进行扩增,采用POPGENE version 1.32软件计算多态性位点数、多态性位点百分率、观测等位基因数(Na)、有效等位基因数(Ne)、Nei’s多样性指数(H)和Shannon信息指数(I),及各材料间的Nei’s遗传相似系数(GS)和遗传距离(GD),并利用NTSYS pc version 2.10e 软件根据Nei’s遗传相似系数采用UPGMA方法进行聚类,以此分析遗传多样性和亲缘关系;利用4个引物特异位点的不同组合及Gel2.0指纹图谱自动识别系统鉴别48个新疆主栽杏品种(系),并利用Gel2.0构建主栽杏品种(系)的DNA指纹图谱库。【结果】从100个ISSR引物中筛选到重复性好、多态性丰富的4个引物作为特征引物,分别为UBC809、UBC836、UBC844和UBC850,共扩增出78个位点,其中73个为多态性位点,平均多态性位点百分率为93.13%,其中引物UBC844多态性位点百分率最高,为100.00%;48个新疆主栽杏品种(系)的观测等位基因数、有效等位基因数、Nei’s基因多样性和Shannon信息指数的平均值分别为1.9313、1.4368、0.2622和0.4028,说明各品种(系)的遗传多样性相对较丰富。‘黄肉油杏’和‘大五月杏’的遗传相似系数为0.8846,遗传距离为0.1226;‘库曼提’和‘索格佳娜丽’的遗传相似系数为0.5641,遗传距离为0.5725。将4个引物两两组合起来,可快速、准确地鉴别46个杏品种(系),只有‘辣椒杏’和‘伊犁阿克玉吕克’需要3个引物组合才能鉴别出来,利用这4个ISSR特征引物通过Gel2.0指纹图谱自动识别系统构建了48个杏品种(系)的DNA标准指纹图谱数据库。【结论】新疆主栽杏品种(系)的遗传多样性较丰富,亲缘关系相对较近,‘黄肉油杏’和‘大五月杏’的亲缘关系最近,‘库曼提’和‘索格佳娜丽’的亲缘关系最远;且ISSR标记适于新疆主栽杏品种的遗传多样性、亲缘关系分析及构建DNA指纹图谱库;指纹图谱库的建立为杏品种(系)的鉴定及品种真实性和纯度奠定了基础,为新品种登记、注册和品种知识产权保护等提供科学依据。  相似文献   
100.
The current study evaluates the effects of early (8th week) and late (16th week of age) weaning of male goat kids on their body growth, testicular growth, sexual behavior, plasma testosterone concentration, and pubertal age. Early (n = 6) and late (n = 7) weaned Beetal bucks were weekly monitored from 18th to 38th week for their body weight, scrotal circumference, testicular volume, testicular echogenicity (via ultrasonography), sexual activities, and plasma testosterone concentration. In comparison to early-weaned, late-weaned bucks showed a marked increase (p < .05) in body weight (11.4 ± 0.8 vs. 13.7 ± 0.6kg), testicular volume (44.1 ± 7.2 vs. 79.8 ± 18.7cm3), scrotal circumference (10.7 ± 0.6 vs. 12.8 ± 0.7cm), and testicular echogenicity (28.3 ± 2.7 vs. 38.3 ± 2.1) from 18th, 28th, 21st, and 24th week onward, respectively. Sexual activities started earlier in late- than early-weaned bucks (22nd vs. 25th week, respectively). Moreover, the sexual behavior index was better (p < .05) after the 34th week in late than early-weaned bucks. The plasma concentration of testosterone (at 39 weeks of age) was relatively more and the onset of puberty was 2–3 weeks earlier (p < .05) in late than early-weaned bucks. In conclusion, age-based early weaning of male kids impairs their testicular growth, sexual behavior, and age at puberty compared to conventional weaning.  相似文献   
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