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281.
282.
The present investigation was undertaken to study the relationship between circulating inhibin and FSH concentrations during the estrous cycle in buffaloes and Sahiwal cattle. The pattern of inhibin concentrations was similar, with peak concentrations on Day -2 (Day 0 = day of estrus) and minimum concentrations on Days 12 and 11 in buffaloes and cattle, respectively. Circulating FSH concentrations were the highest on Day 0 and lowest on Days 8 and 13 in buffaloes and cattle, respectively. Peripheral plasma inhibin concentrations were negatively correlated to FSH concentrations in buffaloes (r = -0.27, P < 0.01) and cattle (r = -0.35, P < 0.01) indicating that inhibin is involved in negative feedback regulation of FSH in both these species.  相似文献   
283.
This paper is a part of our study on the male reproductive system of bonnet monkey. The developmental changes in testis of bonnet monkey were studied qualitatively and quantitatively, at the light microscopy level. Testicular development appears to primarily involve tubular growth that starts immediately after birth. There is a gradual increase in the number of tubules in the prenatal to neonatal stage in testis, without an increase in the volume. Increase in the number of tubules in the neonatal testis was achieved by an increase in the length of the tubules and reduction in the interstitial proportion. Scattered spermatogonial cells in the tubules of neonatal testis indicate the rapid growth rate of the tubules. Increase in tubular length along with diameter seems to be a continuous process until puberty. This is the first report on the developmental changes in the testis during fetal, postnatal and adult stages in the bonnet monkey.  相似文献   
284.
Yak and mithun are two domesticated herbivores of high economic importance to the farming community living in highlands. Improved yak and mithun production could significantly enhance the living standards of these highlanders. Over the years, their dwindling numbers have been a cause of serious concern. In view of the lack of knowledge on the reproductive physiology of these ruminants, studies have been undertaken to investigate their reproductive endocrinology in recent years. This paper attempts to present the latest information on the endocrine changes associated with their various reproductive processes viz. growth and puberty, oestrous cyclicity and oestrous behaviour, ovulation, and, pregnancy and parturition. The paper also provides the recent developments on research done towards the enhancement of yak and mithun reproductive efficiencies through endocrine and embryo biotechniques.  相似文献   
285.
Journal of Plant Diseases and Protection - In 1998, a severe outbreak of malformation and cracking of nuts in coconut palms (Cocos nucifera) was reported in Tamil Nadu State, India. Concentrated...  相似文献   
286.
The aim of this study was to determine the benefits of growth hormone-releasing factor (GRF) on growth and feed conversion efficiency (FCE) in buffaloes. Twelve Murrah buffalo heifers (Bubalus bubalis) of mean age 24.8 months and mean body weight 302.4kg were divided into two groups (treatment and control) with six animals in each group. The buffaloes were given intravenous injections of bovine GRF (bGRF) at a dose rate of 10microg/100kg body weight or an equal volume of saline at 15-day intervals for a period of 9 months. Plasma growth hormone (GH) responses to bGRF challenge were measured in blood samples collected at 90-day intervals on days 1, 90, 180 and 270 and samples were taken at -60, -30, 0, +10, +20, +30, +60, +120 and +180min relative to bGRF injection. Blood samples were also collected weekly by jugular venepuncture for the quantification of plasma GH. The average growth rate (AGR) and FCE of all animals were recorded at 15-day intervals. Plasma GH concentrations increased (P=0.001) steadily following bGRF challenge, peaking 10-20min after challenge and declining to baseline by 180min. In the treatment group, there were no significant differences (P>0.05) in either the peak heights of the GH response or the area under the curve (AUC) of the GH response after bGRF challenge on any of the four occasions of intensive bleeding. There were overall increases in plasma GH concentrations (P<0.01), AGR (P<0.01) and FCE (P=0.05) in the treatment group compared with the control animals. The study showed that GH responsiveness to administration of bGRF at 15-day intervals over 9 months of treatment remained unchanged in buffalo heifers. Exogenous bGRF treatment for a long period can therefore enhance GH release leading to higher growth rates and better feed conversion efficiency in buffalo heifers.  相似文献   
287.
Studies on Indian Green Leafy Vegetables for Their Antioxidant Activity   总被引:1,自引:0,他引:1  
To identify the potential of green leafy vegetables (GLV) as antioxidants, methanolic extracts of Amaranthus sp., Centella asiatica, Murraya koenigii and Trigonella foenum graecum were studied for their antioxidant activity in different systems at multiple concentrations. Total antioxidant activity assessed by phosphomolybdenum method, free radical scavenging activity by 1,1-diphenly-2-picryl hydrazyl (DPPH), reducing power and ferrous ion chelating activity were determined. The GLV were analyzed for ascorbic acid, total and β-carotene and total polyphenol contents. The ascorbic acid, total carotene, β-carotene and total phenolic content (tannic acid equivalents) of the GLV ranged between 15.18–101.36, 34.78–64.51, 4.23–8.84 and 150.0–387.50 mg/100 g GLV, respectively. The extracts were found to have significantly different levels of antioxidant activities in the systems tested. The total antioxidant activity was highest in Murraya koenigii (2,691.78 μmol of ascorbic acid/g sample) and least in Centella asiatica (623.78 μmol of ascorbic acid/g sample). The extract concentration causing 50% inhibition of DPPH (IC50) was determined (M. koenigii < C.asiatica < Amaranthus sp. < T. graecum). The maximum DPPH scavenging activity and reducing power was exhibited by Murraya koenigii. Multiple regression analysis showed that the relationship of total antioxidant activity, free radical scavenging activity, and reducing power with polyphenol and total and β-carotene was highly significant. Paper awarded the Young Scientist Award in Experimental Nutrition at the Young Scientist Award Session of the 39th Annual Meet of the Nutrition Society of India, Hyderabad, India on 15–16th Dec 2007.  相似文献   
288.
The methanol extract of the dried leaves of Abies webbiana was evaluated for antimicrobial activity. The methanol extract showed a broad spectrum of antibacterial activity.  相似文献   
289.
Thirty-eight Indian potato varieties and fifty-two advanced hybrid lines were analyzed for cytoplasm types using both plastid and mitochondrial genome specific markers. Indian genotypes thus analysed could be broadly grouped into 4 cytoplasm types i.e. T/β (69), W/α (18), W/γ (1) and A/ɛ (2). The T/β type cytoplasm, typical of common cultivated potato (ssp. tuberosum) was absent in six released varieties (Kufri Chipsona-1/-2/-3 series, Kufri Jawahar, Kufri Megha and Kufri Himalini) and fifteen out of fifty two hybrids analyzed. This information was further used to predict cytoplasm type on the basis of common shared maternal pedigree in thirty-eight other advanced hybrids, which revealed majority (25) had T/β type cytoplasm with W/α and A/ɛ cytoplasm observed in 12 and 1 genotype, respectively. T/β type cytoplasm was observed in all 28 early bulking hybrids studied along with all old genotypes. It was revealed that considerable broadening of maternal base was observed in recently developed genotypes. W/α type cytoplasm was present in most of processing (all 3 chipping varieties and 9 of 12 MP hybrids) and late blight resistant (11of 23 hybrids) genotypes.  相似文献   
290.
We report the development of an improved cytoplasmic male sterile (CMS) system of Brassica juncea carrying cytoplasm of the wild species Diplotaxis berthautii. Flowers of the CMS line are smaller than the euplasmic line but have improved nectaries. Anthers are slender and fail to extend to the level of stigma. Female fertility of the CMS line is comparable to the euplasmic line. Fertility restorers of Moricandia arvensis and D. catholica-based alloplasmic CMS systems of B. juncea were found capable of restoring male fertility to this new CMS line. The fertility restoration is monogenic and gametophytic. Southern analysis showed that the cytoplasm of the CMS line is different from euplasmic B. juncea and other CMS systems restored by the same restorer lines. Northern analysis of the CMS, fertility restored and euplasmic lines using eight mitochondrial gene probes revealed altered atpA expression associated with male sterility. Cleaved amplified polymorphic sequence (CAPS) markers were identified for the plastid gene psbB, which could be useful for a quick identification of this CMS line. S.R. Bhat and P. Kumar contributed equally to this work.  相似文献   
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