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1.
The aqueous extract of the Cocculus hirsutus aerial parts (100 and 200 mg/kg, p.o.) showed significant diuretic activity and laxative effect in rats. The acute toxicity, orally evaluated in mice, was found to be higher than 3000 mg/kg.  相似文献   
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Mud spiny lobsters, Panulirus polyphagus (Herbst, 1793), were reared at four different stocking sizes and stocking densities in open sea cages to evaluate their effects on growth performance. To evaluate the effect of stocking size on the growth performance, the lobsters were segregated into four different treatment groups according to size and were stocked at a density of 300 animals per cage. To evaluate the effect of stocking density on the growth performance, lobsters of 81–100 g were stocked in four different stocking densities, i.e. 16/m2, 24/m2, 32/m2 and 40/m2. The results showed that the growth rate of (60–80 g) size group, was significantly higher compared to the size groups, i.e. 101–120 g and 121–140 g comprising of larger individuals. The final body weight, though significantly higher in 81–100 g as compared to 60–80 g, the growth performance (i.e. weight gain percentage (WG %) and specific growth rate (SGR)) were not significantly different. The density‐dependent influence on growth performance was evident in this study. The WG % and SGR during 90 days’ culture period was significantly higher in 24/m2 compared to other groups. This study provides crucial information about the appropriate stocking density and stocking size of lobsters at the field level, which would help to promote sustainable lobster cage farming by maximizing the production potential of the system.  相似文献   
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This study aimed to test the efficacy of 17 α‐methyl testosterone (17 α‐MT) alone and in combination with letrozole, an aromatase inhibitor, for the induction of sex reversal in protogynous greasy grouper, Epinephelus tauvina. Further, the long‐lasting effects of these treatments and spawning performance of sex‐reversed males were also investigated. Greasy grouper with oocytes in the perinucleolus stage were implanted with 5 mg 17 α‐MT kg?1 body weight (T1), 5 mg 17 α‐MT and 0.2 mg letrozole kg?1 body weight (T2) and 5 mg 17 α‐MT with 0.4 mg letrozole kg?1 body weight (T3) and no androgens/enzyme inhibitor implanted (C). The 17 α‐MT alone and in combination of letrozole‐induced sex reversal in greasy grouper, whereas untreated control fish (C) showed normal ovarian development. However, T2 and T3 group showed 100% sex reversal and completion of spermatogenesis up to functional male phase in 2 and 3 months, respectively, whereas T1 group resulted in only 66.67% functional male with motile spermatozoa after 4 months. Sex‐reversed males successfully fertilized the eggs during induced spawning. There were significant differences on fertilization and hatching rates between T2 group (79.00 ± 4.36%; 77.67 ± 2.87%, respectively) and T1 group (57.67 ± 3.17%; 63.87 ± 2.91%, respectively). The result suggested that 17 α‐MT (5.0 mg kg?1 BW) in combination with letrozole (0.2 mg kg?1 BW) has the potential to produce 100% sex‐reversed male in short period in greasy grouper, which might greatly help in seed production of greasy grouper.  相似文献   
5.
The present study was conducted to evaluate the effect of dietary supplementation of probiotic bacterium Bacillus licheniformis on the gut microbiota, growth and immune response in Macrobrachium rosenbergii juveniles (4.0 ± 0.02 g). Five isocaloric experimental diets supplemented with different concentrations of B. licheniformis, viz. Control (without probiotic supplementation), T1 (1.0 × 106 cfu g?1feed), T2 (1.0 × 107 cfu g?1feed), T3 (1.0 × 108 cfu g?1 feed) and T4 (1.0 × 109 cfu g?1 feed) were used for the experiment. After 60 days of feeding trial, the growth performance increases significantly in all the experimental groups compared with control, and highest weight gain, specific growth rate and lowest feed conversion ratio were recorded from T4 (P > 0.05). However, juvenile survival was not found to be significantly affected by probiotic supplementation (P > 0.05). The total bacterial count and Bacillus spp. count in the gut were significantly increased with concurrent decrease in pathogenic Aeromonas spp. and Pseudomonas spp. in all the experimental groups compared with control (P < 0.05). Compared with control, immune parameters were increased significantly in all the experimental groups (P < 0.05). Highest haemocyte count, phenol oxidase, superoxide dismutase and antibacterial activity in haemolymph were recorded from T4 (P < 0.05). When prawns were challenged with Vibrio alginolyticus, the cumulative mortality was significantly lower in T4 (P < 0.05). These results indicate that dietary supplementation of B. licheniformis can manipulate the gut microbiota and increase the growth and immune response of M. rosenbergii. In the present study, concentration response on the probiotic effect of B. licheniformis was observed which showed higher effects at a concentration of 1.0 × 109 cfu g?1 feed in the laboratory condition.  相似文献   
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The effects of extender composition, cryoprotectant concentration and freezing and thawing on the fertilization efficiency of cryopreserved spermatozoa of Puntius gonionotus were evaluated. Computer‐aided motility analysis of semen was conducted to check the suitability of spermatozoa for cryopreservation after mixing with different extenders and cryoprotective agents (CPAs). Extender‐4 with an osmolality 260 mOsmol kg−1and pH 7.6 was used for the cryopreservation study. Among the CPAs, dimethyl sulphoxide (DMSO) was least toxic and more than 60% fertilization was achieved when used at 1.4 M at 0 °C for 10 and 30 min, whereas the toxicity of all CPAs to spermatozoa was evident when tested at 30 °C. Semen frozen at −16 °C min−1 with 1.4 M DMSO showed 70% fertilization, which was significantly higher (P<0.05) than other freezing rates. Samples thawed at 35 °C water showed a fertilization rate comparable with that of fresh semen. Computer‐assisted semen analysis of fresh and frozen semen after thawing showed variations in different types of motility in spermatozoa and in their class. There was no significant difference in motility before or after cryopreservation; however, significant differences could be observed in the average path velocity (VAP), straight line velocity (VSL) and curve linear velocity (VCL). Semen of silver barb could be cryopreserved with extender‐4 by addition of 1.4 M DMSO to a final cryopreservation medium (MED 2) cooled at a rate of −16 °C min−1, stored in liquid nitrogen (−196 °C) and utilized after thawing at 35±2 °C.  相似文献   
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1. A total of 433 birds (7 weeks old) of both sexes belonging to Indian native breeds, including, Aseel, Kadakanath, Naked Neck and Frizzle fowl along with the imported breeds Dahlem Red, White Leghorn, Synthetic dam line broiler (SDL) and Naked Neck broiler were utilised to test the primary antibody response to sheep erythrocytes by haemagglutination test. The effect of genotype (breed), sex and their interactions on antibody response were also studied. 2. The results revealed the presence of natural antibodies in all groups under study. 3. All groups except broilers showed the highest HA titre on day 5 post immunisation, which gradually declined until the end of the experiment (19th day post immunisation). In broilers, the peak HA titre was observed on day 12. 4. Dahlem Red showed the highest response throughout. The lowest antibody response was recorded for broilers except on day 19 post immunisation when it exceeded the White Leghorn value. 5. Amongst the native Indian breeds, the Naked neck had the highest titre on day 5 post immunisation but the Aseel titre was highest on days 12 and 19. 6. Males tended to have higher titres than females in Aseel, Kadakanath, Naked Neck, White Leghorn and Naked Neck broilers whereas Frizzle, Dahlem Red and SDL broilers showed the converse. 7. Statistical analysis revealed significant variation in HA response among the various genetic groups on different days post immunisation. The apparent differences between sexes were not significant. However, interactions between breed and sex were significant on day 5 and 19 post immunisation.  相似文献   
9.

Relationship of scrotal bifurcation or splitness with breeding soundness traits was investigated in 15 Beetal bucks (17–20 months of age and 48.72?±?1.57 kg mean BW). Breeding soundness traits of conjoined/unsplit (n?=?6) scrotal bucks was compared with split (n?=?9) scrotal bucks having lengthwise >?1 in. bifurcation. Two consecutive semen ejaculations per buck were collected at monthly interval during summer season (April to June 2018) using intact buck as teaser and sexual behavior was simultaneously recorded. Scrotal morphometry parameters, i.e., scrotal circumference, scrotal volume, scrotal skin thickness, testis length, width, and thickness were also recorded. Bucks with split scrotum had relatively more scrotal dimensions (scrotal circumference (P?<?0.01), scrotal volume (P?<?0.01), testis length (P?<?0.01)) than conjoined scrotal bucks. Among various semen attributes, semen volume of first ejaculate (P?<?0.01), second ejaculate (P?<?0.05), mean semen volume (P?<?0.01), total sperm count of first ejaculate, and mean sperm count of both ejaculates were more (P?<?0.01) in split scrotal bucks. However, scrotal bifurcation had no influence on sexual behavior of bucks. It is concluded that Beetal bucks with split scrotum had relatively better breeding efficiency traits than conjoined scrotal bucks.

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