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11.
Timely onset of postpartum ovarian activity is vital for optimal reproductive performance of dairy cows. Much depends upon genetic constitution of an animal although several factors interplay to govern the onset of postpartum ovarian activity. South Asian zebu cattle have much longer service period when compared with other exotic or crossbred cattle reared in the same Asian environment, which suggests differences in their genetic makeup. However, the cows with same genetic configuration expressed better reproductive potential when reared under different environment, such as in Brazil and Mexico, which suggests the role of extrinsic factors such as management, nutrition, environment and disease conditions. Better management of animals (provision of proper shade, water and housing, efficient oestrous detection and timely insemination), good quality nutrition supplemented with appropriate minerals and vitamins, prevention of diseases (vaccination, deworming, suitable therapeutic interventions) and application of biotechnology have helped in improving postpartum ovarian activity and, therefore, reproductive performance of zebu cattle in Asia. No comprehensive study appears to have been carried out on the various aspects of reproduction in zebu cattle reared under South Asian socio-agro-climatic conditions. This paper is a modest effort to collect what ever information available and to critically review the postpartum ovarian activity in zebu cattle with special reference to the effect of the various managemental practices and pharmacological interventions.  相似文献   
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The present study was conducted with the main objective to optimize petal yield from important marigold cultivars in West Bengal, and to standardize isolation of lutein from petals because these dietary xanthophylls are known to reduce the risks of agerelated macular degeneration (AMD) and cataracts. Six cultivars were studied viz. African marigold-Double (AFM-D), African marigold-Single (AFM-S), African marigold-Orange (AFM-O), French marigold-Orange (FRM-O), French marigold-Double (FRMD), and LC (Local type), which withstand typical environmental conditions of northern West Bengal and produce flowers that do not vary in color and are relatively unaffected by pests and diseases. Lutein esters were extracted from milled marigold petals using nhexane. However, overall performance showed that LC is superior to the other cultivars. Pure lutein was obtained after saponification with 50% KOH. The re-crystallized lutein was characterized by UV-VIS, IR spectroscopy, and HPLC. A free-flowing lutein ester was also formulated. This free-flowing lutein ester was found to be suitable to undergo commercialization or subsequent processing. An economic method for petal yield and isolation of lutein was thus standardized.  相似文献   
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Lipopolysaccharides (LPS), the outer membrane of the Gram-negative bacteria, are reported to stimulate the immunity of different vertebrates including fish. However, their potency and spectrum of actions often differ among different bacteria. In this study, effect of crude LPS, derived from three species of smooth Gram-negative bacterial fish pathogens viz. Edwardsiella tarda, Escherichia coli, and Pseudomonas fluorescens, on certain innate immune parameters of Indian major carp, Labeo rohita was studied. L. rohita yearlings, when injected intraperitoneally with crude LPS extracted from these bacteria showed little variations in different innate immune parameters. Furthermore, LPS injected fish were protected against a virulent E. tarda challenge. Although, no significant difference (p>0.05) in most of the immune parameters were found with LPS of different bacteria, the E. coli LPS injected fish elucidated high resistivity during challenge study. Hence, there could be some variations in LPS with respect to the bacterial type which needs to be further explored.  相似文献   
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The hypophysis cerebri of the goat was studied from a histologic and micrometric point of view. The results of this study are compared with similar studies of other ruminants.  相似文献   
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Cystic ovarian disease in cows was treated either with a single intramuscular injection of 500 micrograms cloprostenol, a prostaglandin F2 alpha analogue, in 77 cases of luteal cysts or with 500 micrograms gonadorelin or 20 micrograms buserelin, gonadotrophin releasing hormone or its analogue (GnRH), in 116 cases of follicular cysts. Recovery was defined as the absence of cysts and the formation of a corpus luteum either with or without observed oestrus within 10 days after treatment with cloprostenol and 15 days after treatment with GnRH. Recovery occurred in 65 per cent and 52.6 per cent of cases, respectively, in average times of 4.9 and 19 days. Fifteen days after treatment with GnRH, 20 cows with luteinised cysts were treated with cloprostenol and 15 recovered in a mean of 20.4 days, while 10 which still had follicular cysts, were given GnRH and one recovered 31 days after the beginning of treatment. Another 27 cows, in which cysts became luteinised, were treated with cloprostenol seven days after treatment with GnRH to give quicker (average 11.5 days) but poor (48 per cent) recovery and with a higher rate (33 per cent) of recurrence of cysts. A progesterone releasing intrauterine device was used in 25 cases of cystic ovarian disease, some of which had been previously treated. Sixty-eight per cent recovered in an average of 15 days. The proportions of cows becoming pregnant to one to three inseminations after the different methods of treatment were similar (77 to 94 per cent).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
17.
The capillary index of the hypophysis cerebri of goats, ranging in age from one day to over 6 years of age. Observations in rostral, middle and caudal regions were made and comparisons are made with other species.  相似文献   
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印度每年可产1500万吨的香蕉,占全球香蕉产量的19%。但因国内消费量过大,导致其出口量所占全球香蕉出口份额不到1%。香蕉生产公司(Bancom)主席称,印度是最大的香蕉生产国和消费国,但还必须增加出口量,而海湾国家将成为印度香蕉出口的主要目标国。由于印度邻近中东市场,运输成本  相似文献   
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A collaborative crop specific exploration and collection mission to collect the germplasm and to study the population size of male and female/hermaphrodite trees of Malabar tamarind [Garcinia cambogia (Gaertn.) Desr.] in the area of its diversity was undertaken during July 2002 in Kerala and Karnataka. A total of 56 accessions of Malabar tamarind were collected. Two collections of Malabar tamarind were found to be very specific because of the uncommon fruit colour, which is pinkish red. All the collected accessions are grown at National Bureau of Plant Genetic Resources (NBPGR) Regional Station, Thrissur for characterisation and conservation. Extensive range of variability was found in fruit colour, shape, size and nature of branching and canopy of trees. Characterisation of 13 fruit and five seed characters was done for 51 accessions. The variability was found to be maximum for nipple length (74.8%) and minimum for fruit girth (12.8%). Two promising accessions were identified based on mean fruit weight (161 g) in IC 354028 and mean rind thickness (15 mm) and mean rind weight (125 g) in IC 354019.  相似文献   
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