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Partial replacement of live feed (LF) with formulated feed (FF) was performed in Betta splendens to evaluate their growth, survival and reproductive performance. Three hundred B. splendens fry of uniform size (mean weight 0.19 g±0.01) were equally distributed in five treatment groups with each of three replicates in glass aquaria of 35 L capacity. Fish were offered diets of different ratio of LF and FF like T1 (control) – 100% LF; T2 – 75% LF, 25% FF; T3 – 50% LF, 50% FF; T4 – 25% LF, 75% FF and T5 – 100% FF. Highest (P<0.05) body weight gain (% BWG) (67.1±1.03) and specific growth rate (2.34±0.02) were observed in the T2 group. Best feed conversion ratio was also found in T2 (2.40±0.11), which was similar to T1 and T3. The highest survival rate (%) was recorded in T1, T2 and T3 groups (97±1.7), which was similar to T4 and the lowest in T5 (49±2.0). The highest gonadal weight (0.12 g±0.01) and gonadosomatic index (15.17±0.50) was observed in the T3 group during the first sampling after 63 days. No significant changes in spawning performance were observed in the second sampling after 21 days after first sampling. However, T4 group registered the highest fecundity and fertilized eggs at the end of 105 days of experiment. From the present study, it concludes that LF can be successfully replaced to the extent of 25% by FF without any detrimental effect on the growth, survival and spawning performance of B. splendens.  相似文献   
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Feng  Ying  Yang  Xing  Singh  Bhupinder Pal  Mandal  Sanchita  Guo  Jia  Che  Lei  Wang  Hailong 《Journal of Soils and Sediments》2020,20(8):3017-3026
Journal of Soils and Sediments - The use of excessive nitrogen (N) fertilizers usually causes soil N leaching, eutrophication, and water pollution. Nevertheless, biochars may play an important role...  相似文献   
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The response of growing quails (n = 900, divided into 36 subgroups) to dietary levels of essential amino acids (EAA) at different energy levels on growth and immunity was investigated. Nine diets including three levels of metabolizable energy (ME, 11.30, 12.13 and 12.97 MJ ME kg− 1) each at three levels of EAA (low, medium and high) in a 3 × 3 factorial design were formulated. Each diet was offered to 4 replicated groups up to 5 weeks of age. The ratio of lysine to protein and the level of methionine and threonine to lysine remained almost similar in all the diets as specified by NRC [NRC, 1994. Pages 44–45 in Nutrients requirements of poultry. 8th ed. Natl. Acad. Press, Washington, DC.]. Body weight gain, feed intake and feed conversion ratio did not differ statistically due to the treatments i.e. interaction of ME and EAA levels. However, there was linear increase in body weight gain with increased EAA levels during 0–3 or 0–5 weeks of age. Feed intake increased linearly with the decreased ME (P < <0.01) and increased EAA (P < 0.01) in diets. Feed conversion ratio (FCR) improved (P < 0.01) linearly with increase in dietary ME concentration from 0–3 or 0–5 weeks of age. FCR and energy efficiency improved in diets with medium and high levels of EAA during 0–3 weeks, while it did not differ during 0–5 weeks of age. Protein efficiency (PE) improved linearly (P < 0.01) with decreased EAA levels during 0–3 or 0–5 weeks of age, and also with the increase in dietary ME level during 0–5 weeks growth phase. Nitrogen retention per unit energy intake was significantly higher in diet containing 12.97 MJ ME kg− 1 with high level of EAA. Humoral (SRBC) and cellular (PHA-P) immune response and yield of immune organs did not differ due to ME, EAA or ME x EAA. Therefore, it can be concluded that the optimum level of dietary ME is 11.30 MJ kg− 1 with CP 25.83%, lysine 1.49%, methionine 0.58% and threonine 1.17% on dry matter basis during 0–5 weeks of age for gain. However for optimum feed conversion, the growing quails require diet with ME 12.97 MJ kg− 1 with CP 23.23%, lysine 1.30%, methionine 0.50% and threonine 1.02% for 0–5 weeks of age.  相似文献   
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Genetic parameters for faecal nematode egg count were estimated in naturally infected Barbari goats maintained at the Central Institute for Research on Goats, Makhdoom, Mathura, India, over a period of 5 years (1999 through 2003). Faecal egg count (FEC) data on 891 records of Barbari goats descended from 69 bucks and 241 does were used in this study. Analyses were carried out by restricted maximum likelihood (REML), fitting an animal model and ignoring or including maternal genetic or permanent environmental effects. Three different animal models were fitted. Direct heritability estimates were inflated substantially for this trait when maternal effects were ignored. The direct heritability estimates for the trait ranged from 0.05 to 0.13 depending on the model used. Low (0.04) maternal heritability estimate was observed for this trait in our study. Moderate estimate of the fraction of variance due to maternal permanent environmental effects (c(2)) for faecal egg count (c(2)=0.10) was also observed. Results suggest that direct and permanent environmental maternal effects were important for this trait, however, maternal additive effects had less impact on this trait.  相似文献   
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The present study was carried out to study the effect of different doses of hemp seed alone or in combination with dill seed against antibiotic growth promoter on performance, serum biochemicals and gut health of broiler chickens over a period of 42 days. Total 192 broiler chicks were grouped randomly into six treatments and fed with basal diet (BD) along with different levels of seeds, viz., T1 (BD), T2 (BD + 0.2% HS), T3 (BD + 0.2% HS + 0.3 DS), T4 (BD + 0.3% HS) and T5 (BD + 0.3% HS + 0.3 DS) and T6 (BD + 0.025% Bacitracin Methylene Disalicylate‐BMD). The performance traits like feed intake, body weight gain and feed conversion ratio (FCR) and carcass traits like cut‐up parts, giblet and abdominal fat yield remained unaffected due to dietary treatments for overall trial period; however, the average feed intake in early phase (0–3 weeks) reduced significantly (p < 0.05) in treatment birds than both controls (T1 & T6). Serum protein concentration remained unchanged, whereas significant (p < 0.05) reduction in serum lipids like triglyceride, LDL and total cholesterol concentration was noticed due to dietary inclusion of seeds. Serum enzymes like AST and ALT concentrations depleted significantly (p < 0.05) treated groups, except at higher seed doses (T5); however, alkaline phosphatase levels were unaffected. Coliform count in caecum and jejunum reduced linearly (p < 0.01) due to seed inclusion, whereas dose‐dependent proliferation of lactobacilli was evident (p < 0.01) in caecum and jejunum of treated birds. No effect was observed on the villus height and crypt depth of the jejunal mucosa. To conclude, dietary supplementation of hemp and dill seed could not affect the growth performance and carcass traits; however, it positively altered the serum lipid profile of the birds and improved gut health as well, thereby enhanced overall performance of broiler chickens.  相似文献   
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Two hundred turkey breeder hens and 24 viable toms of 30–35 weeks age of small white variety were distributed into two treatment groups having four replicates of 25 hens and three toms in each treatment. First four replicates were offered a turkey breeder diet (Diet A) (Nutrient requirements of poultry, 1994, National Academic Press, Washington, DC) and the rest four replicates were maintained on a higher plane of nutrition (Diet B) for 8‐week duration. After 6 weeks of experimental feeding, two replicates from each treatment groups were vaccinated with ND (R2B) vaccine. Yolk sac of embryo from birds fed Diet B had a significantly higher (p < .05) IgG, IgM level and HI titre (log 2) than those fed Diet A. HI titre values of embryonic yolk sac from the vaccinated birds fed Diet B were significantly higher (p < .05) than that of the control groups. In addition, HI titre values were significantly higher (p < .05) in the day‐old poults of the birds fed Diet B than that of those fed Diet A. There was significantly (p < .01) positive correlation between serum IgG and IgM of the breeder birds and day‐old chicks. Similarly, there was significantly (p < .05) positive correlation between yolk IgG and IgM after 1‐month experimental feeding and yolk sac IgG and IgM. Positive correlation (p < .05) also existed between yolk sac IgM and day‐old chick serum IgM. Furthermore, the HI titres of breeder birds' serum at 14 days post‐vaccination were positively correlated with their egg yolk after 10 and 15 days post‐vaccination, yolk sac and day‐old chicks. Thus, the study envisaged that a higher immunity in neonate poults from turkey breeders maintained on a higher plane of nutrition may be elicited as there was maternal transfer of antibodies from the serum of breeder birds to their offsprings through their yolk sac.  相似文献   
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