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1.
Faecal samples from 434 calves under 1 year of age (307 diarrhoeal and 127 normal) were collected from three dairy farms and one village in selected areas of Bangladesh. The samples were tested by an enzyme-linked immunosorbent assay (ELISA) to detect the presence of rotavirus antigen. Of 402 dairy calves tested, 28 (7.0%) were positive, of which 21 (7.2%) were from diarrhoeic calves and 7 (6.3%) from non-diarrhoeic calves. Rotavirus infection varied from farm to farm (2.7–9.2%) and there was no positive response from any of the 32 village calves. Rotavirus was most commonly found in calves of 1 week of age or less (up to 22.2% in one group) but was not found in any calves later than 6 months of age. More than 80% of rotavirus-positive samples from diarrhoeic calves exhibited a titre of 128 or more (geometric mean 345±4.5), whereas non-diarrhoeal calves had titres less than or equal to 128 (geometric mean=29±1.9), suggesting that rotavirus infection in calves in Bangladesh was mostly associated with diarrhoea.  相似文献   
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Tropical Animal Health and Production - In this study, the seroprevalence and distribution of Leptospira in dairy cattle in endemic states of India were investigated in association with...  相似文献   
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The objective of this study was to determine the effects of dietary supplementation of Nigella sativa L. seeds, Rosmarinus officinalis L. leaves and their combination on rumen metabolism, nutrient intake and digestibility, growth performance, immune response and blood metabolites in Dorper lambs. Twenty-four entire male Dorper lambs (18.68?±?0.6 kg, 4–5 months old) were randomly assigned to a concentrate mixture containing on a dry matter basis either, no supplement (control, T1), 1% R. officinalis leaves (T2), 1% N. sativa seeds (T3) or 1% R. officinalis leaves +1% N. sativa seeds (T4). The lambs had ad libitum access to urea-treated rice straw (UTRS) and were raised for 90 days. Supplemented lambs had greater (P?< 0.05) intake of DM and UTRS than the control lambs. The T4 lambs had lower (P?< 0.05) nutrient digestibility than those fed other treatments. Total and daily weight gain was greater (P?< 0.05) in T2 lambs than those fed other diets. The T3 and T4 lambs had greater (P?< 0.05) ruminal pH than the T1 and T2 lambs. Supplemented lambs had lower (P?<?0.05) ruminal total volatile fatty acids, acetate, propionate, NH3-N and C18:0 than the control lambs. The T4 lambs had lower (P?< 0.05) population of Fibrobacter succinogenes, Ruminococcus albus, methanogens and total protozoa compared with those fed other diets. Supplemented lambs had lower (P?< 0.05) neutrophils, basophils and serum urea and greater (P?<?0.05) serum IgA and IgG compared with the control lambs. The current results emphasised the variation in the efficacy of medicinal plants in ruminant nutrition.  相似文献   
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Recent studies have demonstrated a strong relationship between the intestinal microbiota and the host health. As such, consumers are increasingly becoming more concerned about the potential effect of certain foods/feeds, particularly of transgenic origin on the gut microbiota. Although the European Food Safety Authority has recommended in their guidelines, to study the effect of transgenic food/feed on host-microbiota, yet, few studies have focused on the evaluation of such effects mainly due to culturing difficulties. Therefore, this study was intended to evaluate the potential adverse effects of transgenic diet consumption on some specific gut microflora (Lactobacillus group, Bifidobacterium genus, Escherichia coli subgroup and Enterococcus genus) of rabbits. A total of forty-eight rabbits were randomly assigned into four groups and fed a diet containing a variable proportion of transgenic cottonseeds at 0, 20, 30 and 40% inclusion level, respectively. Changes in the specific or total faecal bacterial population were monitored at five different experimental stages (i.e. 0, 45, 90, 135 and 180 days) using both the traditional plate count method (TM) and quantitative real-time PCR (qPCR). No significant differences (p > .05) were observed concerning numbers of specific bacteria or total bacteria between the control and experimental groups, though qPCR showed numerically higher values in terms of 16S rRNA gene copies as compared to the values obtained from TM. However, such numerical differences were biologically insignificant (p > .05). Similarly, no significant variations were noticed in the calculated B/E (log10 copies of Bifidobacterium per g faces/log10 copies of E. coli genome per g faeces) ratios in all the groups. All the ratios were in the range of 1.24 to 1.30 throughout the experiment, indicating a good balance of intestinal microflora and greater resistance to intestinal disorders. It is therefore concluded that feeding transgenic cottonseeds could not adversely affect the gut microflora of rabbits during a long-term study.  相似文献   
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In this study, we tried to optimize the porcine semen extender conditions to maximize the differences between live X chromosome-bearing (X) spermatozoa and to Y chromosome-bearing (Y) spermatozoa without a decline in the fertility rate at different pH conditions during storage. We observed the viability of X and Y boar spermatozoa in acidic (pH 6.2), original (pH 7.2), and alkaline condition (pH 8.2) for 5 days to investigate the effect of storage conditions on the X to Y spermatozoa ratio. The functional parameters of spermatozoa were also examined to evaluate sperm quality. Sperm motility was preserved at pH 7.2 and pH 6.2 for 3 days, while sperm motility at pH 8.2 decreased significantly after 2 days. Non-capacitated spermatozoa increased while capacitated spermatozoa decreased during storage. Sperm viability decreased significantly duration-dependent under all pH conditions, but there was no significant difference during storage at pH 6.2 and 7.2. The X: Y ratio of live spermatozoa in acidic condition was maximized (1.2:1) without affecting the sperm function and fertility-related protein expression after 2 days compared to original conditions. Moreover, insemination of sows using acidic extender increased the number of female pups on days 1 and 2 of preservation. These results indicate that the production of female offspring may increase when acidic BTS is used for 2 days without affecting the success rate of AI. Above all, this method is simple and economical compared to other methods.  相似文献   
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Year by year, huge quantities of by-products are generated during the manufacturing process of soybean-based products. Okara is one of the by-products, and it is an insoluble portion of the soybean. It consists of high moisture (8.4–22.9%); on dry matter basis, it contains high metabolizable energy (9.0–14.2 MJ/kg) and other components that include crude protein (20.9–39.1%), crude fiber (12.2–61.3%), crude fat (4.9–21.5%), and ash (3.4–5.3%). Fermentation of okara improves its nutritional quality and reduces its anti-nutrient contents. Due to animals' palatability, okara can be used to replace the soybean meal/concentrate feed partially or completely in ruminant's diet and partially in nonruminant's diet. Okara feeding does not depress the intake, digestibility, growth, milk production, blood metabolic profiles, and meat quality of animals. However, this by-product decays quickly due to its high moisture content, and its heavy weight and sticky nature make it difficult to process and expensive to dry using conventional methods. This paper thoroughly summarizes the utilization of okara as animal feed in the cause of developing a general guideline with favorable levels of inclusion in the diets of animals for its exploitation and valorization. This review will encourage further research to develop eco-friendly and value added feed for animals.  相似文献   
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The aim of the present study was to evaluate the expression and localization of lymphangiogenic factors (VEGF-C and VEGF-D), their receptor (VEGFR3) and lymphatic endothelial marker (LYVE1) in buffalo placenta during early pregnancy [EP], and to investigate the functional role of lymphangiogenic growth factors in placental lymphangiogenesis. The mRNA and protein expression of VEGF-C, VEGF-D, their receptor VEGFR3 and LYVE1 showed significant expression in EP1 (29–42 days) and EP2 stages (51–82 days) both in caruncle (maternal part) and cotyledon (foetal part) of the buffalo placenta. Immunoreactivity of VEGF-C, VEGF-D and LYVE1 was observed around the endometrial gland, in lymphatics and trophoblast cells, whereas VEGFR3 mainly localized in lymphatics of the caruncle and cotyledons. Cultured trophoblast cells were treated with VEGF-C/VEGF-D (50, 100 and 150 ng/ml) and combined doses of VEGF-C and VEGF-D (150 ng/ml) each for different time durations (24, 48 and 72 h). The mRNA expression of LYVE1 and PCNA was significantly (p < .001) upregulated with VEGF-C and VEGF-D and combined treatment (@150 ng/ml), as well as significantly downregulating Caspase-3 at 48 and 72 h. Thus, the present study provides evidence that lymphangiogenic factors are expressed in buffalo placental compartments and they may play a significant role in the regulation of placental function in water buffaloes.  相似文献   
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Giant river prawn (Macrobrachium rosenbergii) farming plays an important role in the economy of Bangladesh. Presently, it is cultured in around 50 000 ha area with total annual production of 23 240 t. Traditional extensive prawn farming has been expanding over the last three decades through the introduction and adoption of improved culture systems, such as culture of prawn‐carps, prawn‐shrimp‐fish and prawn‐fish‐rice as concurrent and rotational systems. Efforts for the development of improved techniques on broodstock management, seed production and rearing and grow‐out of prawn have been made over the last decade. The outcomes are low‐cost feed for broodstock, production of post‐larvae in net cages (hapa), all‐male prawn culture, periphyton based prawn‐tilapia culture, C/N based prawn culture, organic prawn farming, prawn‐mola culture and prawn‐carp‐mola polyculture. Despite the development of culture technologies, a number of challenges for sustainable development of prawn farming need to be overcome to realize the potentials of this promising sector. Good aquaculture practises at all levels and application of measures for quality control and food safety would ensure sustainable development of prawn farming in Bangladesh.  相似文献   
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