Dietary taurine improves reproductive performance of Nile tilapia (Oreochromis niloticus) broodstock

This study was conducted to evaluate the effects of supplemental taurine on reproductive performance of Nile tilapia (Oreochromis niloticus) broodstock fed soybean meal‐based diets. Four isonitrogenous (350 g kg^?1 protein), isocaloric (18 MJ kg^?1) diets were formulated to contain 0, 5, 10 and 15 g kg^?1 taurine. The diets were fed to triplicate groups of juvenile Nile tilapia (10–15 g average body weight) at a female: male ratio of 3 : 1, to apparent satiation, three times per day for 130 days. The size at first maturation decreased with increasing dietary taurine to 10 g kg^?1 and levelled off with further taurine supplementation. The time to first spawning was also significantly shorter at 10 g kg^?1 taurine level. Spawning performances, including spawning frequencies, total number of spawnings per tank, number of spawnings per female and absolute fecundity, were all significantly improved with increasing dietary taurine up to 10 g kg^?1. However, the quadratic regression analyses indicated that the maximum spawning performance occurred at 8 g kg^?1 of supplemental taurine. Eggs produced from broodstock fed 10 g kg^?1 taurine exhibited significantly higher hatchability and required shorter time for hatching and yolk‐sac absorption and also resulted in higher larval weight than at other dietary taurine levels. The highest egg protein, total amino acids and taurine were also obtained at 10 g kg^?1 taurine. These results suggest that 8 g kg^?1 dietary taurine is required for optimum reproductive outputs of Nile tilapia broodstock.     

鸡胚注射肉碱对肉鸡孵化率、生长和屠宰性能的影响

文章旨在研究体外鸡胚注射肉碱对肉鸡孵化率及出壳后49 d肉鸡生长性能和屠宰性能的影响。鸡胚在孵化第18天通过羊膜注射0.6、2.4和9.6 mg左旋肉碱/100μL稀释液,此外还有3个对照组(非注射组、穿孔组和注射稀释液组),评估肉鸡孵化率、生长期肉鸡死亡率、增重、采食量和料比以及屠宰性能指标(屠宰率、腹脂、小腿肌、大腿肌、鸡翅和胸肌占比)。结果发现:鸡胚注射左旋肉碱对受精蛋孵化率无显著影响(P>0.05),但随左旋肉碱注射量的增加,受精蛋孵化率和仔鸡出壳时间有升高趋势(P=0.08)。鸡胚注射左旋肉碱对出壳后49 d肉鸡生长性能、死亡率及屠宰性能指标均无显著影响(P>0.05)。结论:鸡胚注射0.6、2.4和9.6 mg左旋肉碱/100μL稀释液对出壳后肉鸡生长性能和屠宰性能无显著影响,但可以改善肉鸡出壳时间和受精蛋孵化率。     

Sound exposure and its beneficial effects on embryonic growth and hatching of broiler chicks

ABSTRACT

1. The physical factors that involve artificial incubation determine embryonic growth and hatching of broiler chicks, and have important implications for the poultry production chain and chick welfare. This study explored the effects of sound exposure on incubation responses (hatching, embryonic development and chick quality).

2. A 2 × 2 factorial experiment with the factors ‘sound pressure level’ (at 70 and 90 dB) and ‘species-specific vocalisations’ (at 75dB - 85dB) was performed in four experimental incubators (loaded with 90 eggs each) for eight consecutive cycles of incubation, totalling 2880 Cobb-500® broiler breeder eggs.

3. Embryonic growth was not influenced by any experimental factor, but the highest sound pressure level (90 dB) led to earlier hatching, higher hatchability, better chick quality and lower weight at hatching. Additional effects of species-specific vocalisations were found at 70 dB noise, which caused early hatching and better chick quality.

4. It was concluded that the loud noise found in commercial hatcheries (at 90 dB) can be beneficial. Furthermore, the presence of species-specific vocalisations could improve the hatching time and chick quality from experimental incubators (at 70 dB). However, this would not provide additional benefits in commercial hatcheries, due to the machinery noise masking them.     

肉鸭种蛋重与蛋形指数对孵化效果的影响

将肉鸭种蛋按蛋重、蛋形指数大小各分为5组,在相同条件下孵化.结果表明,蛋重、蛋形指数对受精率和早期死胚率无显著影响(P>0.05),蛋重为85.5～100.6g(D,E)组、蛋形指数为1.15～1.25(F)和1.59～1.69(J)组中后期死胚率显著升高;蛋重为75.3～85.4g时,受精蛋孵化率和入孵蛋孵化率最高,分别为91.4%～95.7%和85.3%～89.3%;蛋形指数为1.26～1.47时,受精蛋孵化率和入孵蛋孵化率最高,分别为90.9%～97.2%和86.7%～93.3%.     

二郎山山地鸡不同产蛋阶段对种蛋孵化效果的影响

为研究不同产蛋阶段对种蛋孵化效果的影响,实验选取二郎山山地鸡种鸡群4个不同产蛋阶段,分别收集种蛋孵化,测定孵化效果。结果表明:不同产蛋阶段的种蛋与其受精率、受精蛋孵化率和健雏率都有着密切的关系。以32周龄种蛋孵化效果最优,40周龄次之,再次为25周龄,最差为48周龄。研究结果表明产蛋阶段对种蛋孵化效果有重要的影响。     

柞蚕种茧感温方式对成虫产卵的影响

采用恒温和变温两种感温方式对柞蚕种茧进行暖茧，研究两种感温方式对柞蚕成虫的产出卵率及卵的普通孵化率的影响。结果表明：变温方式比恒温方式符合柞蚕成虫的生理发育节律，有利于成熟卵粒的形成，对提高柞蚕成虫产出卵率有更好的促进作用，而两种感温方式对柞蚕卵的普通孵化率的影响没有显差别。     

胚蛋注射乳酸菌对蛋雏鸡早期生长发育及免疫功能影响的研究

试验旨在探讨胚蛋注射乳酸菌对蛋雏鸡孵化性能、免疫器官指数、十二指肠中SIgA以及血清中白细胞介素2(IL-2)和干扰素γ(IFN-γ)含量的影响.将300个海兰褐蛋鸡种蛋随机分成4组,每组5个重复,每个重复15个种蛋.18日胚龄时,试验Ⅰ、Ⅱ、Ⅲ组分别向羊膜腔内无菌注入0.2 mL含活菌数2×106、2×107和2×1...     

金属离子Ni2+和Co2+对卤虫孵化率和变态率的影响

在去除重金属离子的天然海水中添加不同浓度的Ni^2 和Co^2 进行养殖实验，研究了Ni^2 和Co^2 对盐卤虫（Artemia saline)孵化率及变态率的影响。在试验过程中保持温度（27℃）、盐度（30‰）以及pH(=8)恒定。结果表明：当海水中Ni^2 和Co^2 浓度分别为40μg/L和30μg/L时对旧金山湾卤虫的孵化最为有利，当Ni^2 浓度为40μg/L,Co^2 浓度为40μg/L-50μg/L时对其发育变态最为有利。从而得出结论：当海水中Ni^2 浓度在40μg/L范围左右时可促进卤虫的孵化及变态发育，当海水中Co^2 浓度为30μg/L-50μg/L范围内时可促进卤虫的生长发育。     

Evaluating hydrolyzed yeast in the diet of broiler breeder hens

One of the greatest challenges for nutritionists is ensuring that breeder hens consume the quantity of nutrients necessary to ensure proper development while also ensuring the production of good quality chicks. However, new studies must investigate how nutrition can positively affect the performance of these poultry. The present study aimed to evaluate hydrolyzed yeast supplementation in the diet of Cobb 500 broiler breeder hens, starting from 25 wk of age, and to evaluate the performance of the hens and their progeny. Broiler breeder hens fed hydrolyzed yeast supplement exhibited better performance compared with the control group. The results of the progeny demonstrated improved performance in chicks from the breeder hens fed the hydrolyzed yeast supplement. However, no improvement was observed in breast or leg yields; only carcass yield improved in these broilers. The results demonstrate that supplementation with hydrolyzed yeast in the diet of broiler breeder hens improves the performance of hens and their progeny.     

Cassava root chips andMoringa oleifera leaf meal as alternative feed ingredients in the layer ration

A study was conducted to evaluate effects of cassava root chips (CRC) andMoringa oleifera leaf meal (MOLM) inclusion in layer rations on egg laying performance, egg quality parameters, fertility, and hatchability. One hundred twenty Dominant CZ layers, 22 wk of age, and 12 cocks were used and equally divided into 4 dietary treatments with 3 replications. Treatment rations contained CRC and MOLM [i.e., T₁ (0% CRC and 0% MOLM), T₂ (50% CRC and 0% MOLM), T₃ (0% CRC and 5% MOLM), and T₄ (50% CRC and 5% MOLM)]. The CRC and MOLM were used to substitute for 100% corn grain and 5% soybean meal, respectively. Hens were weighed at the start and end of the experiment and BW change was calculated. Data on DM intake, hen-day egg production, egg weight, and egg mass were recorded daily. Egg quality parameters were determined at an interval of 15 d on 4 eggs per replicate. Fertility and hatchability of eggs, as well as mortality of birds and embryonic mortality of fertile eggs during the incubation period were recorded. From the chemical analysis, the calculated ME content of CRC was 3,852 kcal/kg of DM and the CP content of MOLM was 28%. The DM intake of birds, hen-day egg production, egg mass, FE, and mortality rate were not influenced by treatments. Body weight change and egg weight were higher for T₄ as compared with other treatments. Most external and internal egg quality parameters, especially yolk color, were improved when the diet contained MOLM. Fertility showed nonsignificant differences among treatments. However, hatchability percentage for T₁ was lower than the other treatments. In conclusion, CRC at 50% of the diet, CRC replacing corn grain 100%, or MOLM at 5% of the diet replacing soybean meal can impart similar or better positive effects on egg production, egg quality parameters, eggs fertility, and hatchability of Dominant CZ layers. Thus, 50% CRC, 5% MOLM, or a combination of both can successfully be used in the diet of layers as energy and protein feed ingredients, respectively.