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试验旨在研究芽孢杆菌微生态制剂对京红1号蛋鸡产蛋性能和蛋品质的影响。选择健康、体况良好的404日龄京红1号蛋鸡960只,随机分为4组,每组6个重复,每个重复40只。对照组饲喂基础日粮,试验Ⅰ组饲喂基础日粮+益倍佳(凝结芽孢杆菌),试验Ⅱ组饲喂基础日粮+赐尔健(纳豆芽孢杆菌),试验Ⅲ组饲喂添加地衣芽孢杆菌+枯草芽孢杆菌(1∶1)混合制剂的日粮,试验组微生态制剂的添加量均为300 mg/kg。试验期25 d,其中预饲期5 d。结果显示,与对照组相比,试验组蛋鸡产蛋率均显著提高(P<0.05),破、软蛋率均显著降低(P<0.05),试验Ⅰ、Ⅱ组料蛋比显著降低(P<0.05)。与对照组相比,Ⅱ组鸡蛋平均蛋重显著提高了2.25%(P<0.05);试验组Ⅰ、Ⅱ的蛋黄相对重、蛋壳相对重、哈氏单位均无显著影响(P>0.05);试验Ⅲ组蛋壳颜色为1~3级的鸡蛋比例明显增多,差异显著(P<0.05)。综上所述,添加微生态制剂赐尔健(纳豆芽孢杆菌)可显著提高京红1号产蛋率和平均蛋重,显著降低料蛋比和破、软蛋率;添加枯草芽孢杆菌+地衣芽孢杆菌(1∶1)混合制剂可使蛋壳颜色加深的鸡蛋比例显著增多。 相似文献
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Tea Bai J. Robert Britton Stephen P. Rice Andrew G. Pledger 《Ecology of Freshwater Fish》2019,28(1):110-122
The spawning success of lithophilic salmonids is strongly influenced by the fine sediment content (“fines”) of spawning substrates, yet knowledge on the impacts of fines on the spawning of non‐salmonid lithophiles remains limited, despite their ecological and socio‐economic importance in European rivers. Consequently, the aim here was to use an ex‐situ experiment to investigate the impact of sand content on egg survival and timing of larval emergence of the surface‐spawning cyprinid European barbel Barbus barbus. Thirty incubator boxes within a recirculating system were filled with one of five experimental sediment mixtures (0%–40% sand by mass) that each contained 300 fertilised eggs at a depth of 50 mm. Emerged, free‐swimming larvae were captured and counted daily to assess grain‐size effects on larval survival and emergence. Specifically, total proportion of emerged larvae, cumulative daily proportion of emerged larvae and time required to reach 50% emergence were measured during the study. Whilst the proportion of sand in the sediments did not have a significant impact on egg‐to‐emergence survival (mean survival per treatment 75%–79%), it significantly affected the timing of larval emergence to the water column; early emergence was detected in treatments with elevated sand content (on average, 50% emergence after 12–13 days versus 19 days in the control). Similar to findings from salmonid studies, these results suggest high sand content in spawning gravels can influence timing of larval emergence and potentially cyprinid lithophilic fish survival. 相似文献
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《The Journal of Applied Poultry Research》2015,24(3):371-379
A total of 3,240 female Taisheng pigeons at 40 wk age were fed 9 diets containing 3 ME levels (2,630, 2,770, and 2,940 kcal/kg) and 3 CP levels (14.0, 15.0, and 16.0%) in a factorial arrangement. These diets were fed to investigate the effects of ME and CP on performance, egg quality, and nutrient digestibility. Female pigeons were housed under the same managerial conditions and randomly assigned into 9 treatments (6 replicates of 60 birds each). Two female–female paired pigeons housed in one cage were under a 16L:8D lighting cycle. Feed in pellet form and water were provided for ad libitum consumption. The study lasted 12 wk. As dietary ME level increased from 2,630 to 2,940 kcal/kg, BW, egg production, and apparent DM, crude fat (CF), and phosphorus (i.e., P) digestibilities increased (P < 0.05), feed intake decreased (P < 0.05), and feed conversion efficiency increased (P < 0.05). Increasing the level of dietary protein from 14 to 16% resulted in an increased (P < 0.05) BW, shell percentage, length of the major axis, and DM digestibility. Therefore, dietary ME had a greater influence on the performance of Taisheng laying pigeons than did dietary protein. 相似文献
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Monsuru Oladimeji Abioja John Adesanya Abiona Obafemi Foluso Akinjute Henry T. Ojoawo 《Journal of animal physiology and animal nutrition》2021,105(4):715-724
Effect of extended storage on egg quality, embryo mortality and hatchability in FUNAAB-ɑ chickens was determined. Hatchable eggs (n = 288; weighing 53.2 ± 4.67 g) collected from a flock of FUNAAB-ɑ layer breeder hens aged 32 weeks were stored in egg tray with broad end up under 16 ± 1.5°C for either 0, 4, 8, 12, 16 or 20 d. Before incubation, eight eggs from each group were evaluated for internal and external quality traits. Remaining eggs were set in an incubator and transferred into hatcher on embryonic day 18. Data collected were subjected to one-way analysis of variance. Egg weight loss (EWL; p < .001), surface area (p < .001), yolk diameter (p < .001), inner and outer blastoderm diameters (p < .05) and dead in germ (DIG; p < .001) increased with storage duration while yolk height (p < .001), yolk index (p < .001), albumen weight (p < .05), albumen height (p < .05), albumen index (p < .01), Haugh's unit (HU; p < .05), fertility (p < .001), hatchability of set (HATCHS; p < .001) and fertile eggs (p < .05) decreased. Weight losses of 0, 1.2, 2.2, 3.4, 4.6 and 6.1% were recorded in egg stored for 0, 4, 8, 12, 16 and 20 days respectively. Eggs stored beyond 8 days exhibited higher DIG and lower HATCHS. Shell percentage in 4 days storage (11.4%) was lower (p < .05) than in 16 days storage (13.4%). Shell thickness was similar in eggs stored for 0 to 12 days, but 8 days storage (0.60 mm) had thinner (p < .01) shell than day 16 (0.71 mm) and day 20 (0.73 mm) storage. Internal quality unit (IQU) was higher (p < .05) in fresh eggs (180.4) than in 12 days (167.8) and 20 days (167.8) stored eggs. Extended storage of FUNAAB-ɑ eggs caused EWL, surface area shrinkage, lowered HU and IQU, loss of yolk and albumen quality, increased blastoderm diameters and DIG, and decreased egg fertility and HATCHS from day 8 forward. Storing FUNAAB-ɑ eggs beyond 8 days reduced quality parameters; therefore, other mitigating factors are recommended when storing beyond 8 days. 相似文献
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Ahmed Abdel-Kareem Abuoghaba Waheed Ezzat Ahmed Mohamed Rizk Ashraf Ahmed Qurtam Osama Abdullah El-Sayed 《Journal of animal physiology and animal nutrition》2021,105(4):725-730
This experiment was designed to investigate and compare the egg production, fertility, hatchability and immune responses of some local developed Egyptian chicken strains under high ambient temperatures. A total of 108 (26 weeks old) laying hens of Matrouh, Silver Montazah, Mandarah and Inshas (9 hens × 3 replicates × 4 strains) were used to evaluate the impact of thermal stress (24-34ºC) during summer season (June, July and August) on egg production, fertility, hatchability and immune responses. The obtained results revealed that final body weight (FBW/g) and body weight change (BWC/g) among different chicken strains were not affected. The daily feed consumption (FC/g) and feed conversion ratio (FCR) for Silver Montazah and Inshas strains were significantly (p ≤ .05) higher than those of Matrouh and Mandarah strains. The mean egg production (EP/%) and egg mass (EM) for Silver Montazah and Inshas strains were significantly (p ≤ .05) higher than those of Matrouh and Mandarah strains. The highest percentages of hatchability of total eggs (HTE) and fertile eggs (HFE) were recorded in Inshas chickens, while the lowest value was recorded in Mandarah chickens. Also, the highest embryonic mortalities (p ≤ .05) and lowest chick weight at hatch (CWH/g) were recorded in Mandarah chickens compared with the other strains. The highest values for antibody titres against phytohemagglutinin-P (PHA-P) were recorded in Mandarah chickens, while the least values were recorded in Inshas chickens. 相似文献
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文章旨在评估不同饲养方式对蛋鸡生产性能、蛋品质和血清生化指标的影响。试验选择产蛋性能接近的22周龄海兰褐壳蛋鸡540只,随机分为3组,每组5个重复,每个重复36只。笼养组蛋鸡采用三层阶梯饲养(0.6 m2/只),网上平养组蛋鸡在金属网丝上饲养(1.5 m2/只),垫料平养组在平铺20 cm稻壳的水泥地板上平养(1.8 m2/只)。试验共开展28周,包括2周的适应期。结果:网上平养和垫料平养组24~36 w和24~29 w蛋鸡平均日采食量较笼养组蛋鸡分别显著提高5.71%、6.22%和4.81%、4.48%(P<0.05)。此外,垫料平养组24~36 w和24~49 w蛋鸡的料重比较笼养组分别显著提高7.31%和4.09%(P<0.05)。在36 w时,垫料平养组鸡蛋的蛋壳强度最高,脏蛋率最低(P<0.05)。在49 w时,笼养组鸡蛋的蛋壳厚度最低(P<0.05),脏蛋率最高(P<0.05)。笼养组蛋鸡血清葡萄糖、甘油三酯、总蛋白和胆固醇浓度均最高(P<0.05),但高密度脂蛋白浓度最低(P<0.05)。结论:网上平养和垫料平养可以提高蛋鸡采食量,但笼养蛋鸡的饲料效率表现最佳。此外,垫料平养提高了鸡蛋的蛋壳强度和蛋壳厚度,降低了破蛋率。 相似文献