Incubation temperature profiles affect broiler feathering

Two experiments were conducted to assess the effects of incubation temperature profiles, breeder feed restriction programs, and litter conditions on progeny feather follicle (FF) density and skin layer thickness. In the first experiment, Cobb 500 fast feathering breeders were subjected to 2 feed restriction programs during rearing: skip-a-day (SAD) and every-day feeding (EDF). Eggs from each group were incubated according to 2 incubation temperature profiles: standard (S) and early-low late-high (LH). A total of 72 chicks per treatment combination were placed in Petersime cages (6/cage) and sampled for skin in the breast, dorsum, and thigh areas at 22 d. Additional samples were collected from the thigh and measured for epidermal and dermal thickness. For the second experiment, 2,475 eggs from a commercial flock of Cobb 500 fast feathering breeders were subjected to 3 incubation temperature profiles: S, LH, and standard-high (SH). At hatch, 1,260 chickens were placed in floor pens (14/pen) that contained either used litter or new wood shavings. At 28 d of age, 2 chickens per pen were sampled for skin in the breast, dorsum, and thigh areas. In both experiments, FF were counted in 4.5 cm². It was concluded that incubation temperature affected feathering development in both experiments, especially in the breast. This effect may be stronger in progeny from breeders restricted under SAD programs. Moreover, litter conditions impacted FF numbers. These findings may be applied to minimize carcass scratches and improve broiler welfare.     

The first report on the winter breeding life history of Epuraea domina (Coleoptera: Nitidulidae) in a citrus grove in Jeju,Korea

Epuraea domina Reitter (Coleoptera: Nitidulidae) is a flower-visiting insect and a pest that causes corky scar on citrus fruit. This study was conducted to investigate the life cycle of E. domina in a citrus grove. E. domina showed the characteristics of cold breeders as they complete key life history events of oviposition and immature development during the winter. E. domina adults spent the summer in uncultivated habits started to lay eggs in soil near fallen citrus fruit in orchards during late autumn. Oviposition activity continued throughout the winter with a large decrease in activity when the minimum air temperature was <0 °C. Hatched larvae fed on decaying citrus and pupated in soil in the spring. The pupae emerged as new adults in mid-May to feed on the pollen and nectar of citrus flowers, probably followed by their migration to uncultivated habitats in the summer.     

灭活蜂胶菌对种鸡大肠杆菌病的防治效果

河南某种鸡场饲养4.5万只种鸡,发生大肠杆菌病。从68只病死鸡脏器中分离到27株大肠杆菌,对其中10株大肠杆菌进行了鉴定和分型,结果表明:90.9%大肠杆菌为O78,9.1%大肠杆菌为O74。将O78、O74制成灭活蜂胶苗,免疫该场青年鸡,发现使用安全、效果好,免疫后的180 d保护率仍达到100%。免疫过的鸡群因大肠杆菌病的死亡率低于1%~5%,产蛋率平均高5%~10%。     

日粮铬水平对热应激种公鸡免疫功能及蛋白质代谢的影响

选用72只35周龄罗曼褐种公鸡随机分成6组,每组12只,对照组饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组分别在基础日粮中添加酵母铬0.2、0.4、0.6、0.8、1.0 mg/kg,探讨日粮铬水平对热应激种公鸡免疫功能及蛋白质代谢的影响.结果显示:与对照组相比,试验Ⅲ、Ⅳ、Ⅴ组热应激种公鸡血清中牛血清白蛋白抗体滴度、免疫球蛋白含量、血清总蛋白、白蛋白含量显著提高,全血T淋巴细胞转化率增强.     

日粮铬水平对热应激种公鸡睾丸组织结构及血浆生殖激素的影响

选择72只35周龄罗曼褐种公鸡,随机分为6组,每组12只,对照组饲喂基础日粮,分别在基础日粮中添加0．2、0．4、0．6、0．8、1．0mg／kg铬量的酵母铬,作为试验Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ组,来探讨日粮铬水平对热应激种公鸡睾丸组织结构及血浆生殖激素的影响。结果表明,在热应激条件下,给种公鸡日粮中添加0．8～1．0mg／kg铬量的酵母铬可有效缓解热应激对种公鸡睾丸生精机能的抑制作用,提高种公鸡血浆睾酮（T）、促黄体素（LH）和促卵泡素（FSH）的含量。     

应用激素调节剂提高黄羽肉种鸡产蛋性能的探讨

选取同一栋同一排的半架全阶梯鸡笼的肉种鸡,随机分为3组,I组21只鸡,每只每天喂服克罗米芬12.5 mg,连喂4d,间隔4d再喂服克罗米芬4d,剂量不变;II组30只鸡,每只每天喂服溴隐停0.5 mg,连喂5d,间隔5d再喂服溴隐停5d,剂量不变;III组为对照组588只鸡,不喂服药物。分别测定各组黄羽肉种鸡产蛋率、种蛋合格率、平均蛋重、双黄蛋率、破蛋率的影响。结果表明,药物处理后的24d内I组I、I组、III组的产蛋率分别为72%,85%,70%;种蛋合格率分别为94%,92%,96%;破蛋率分别为0.8%,1.5%,1.6%;双黄蛋率分别为1.8%,2.1%,1.4%。结果显示使用溴隐停和克罗米芬能够提高黄羽肉种鸡的产蛋性能。     

浅析马铃薯原原种繁殖的影响因素

脱毒马铃薯原原种繁殖是脱毒原种繁殖的基础,其质量的好坏直接影响原种繁殖的质量,因此,要求严格。在生产过程中很多因素都会对原原种的繁殖产生影响,比如培养基质、营养液的配比及苗源的差异等。为了获得数量和质量双优的原原种,介绍了原原种繁殖的影响因素及其对原种繁殖的影响,并简述了原原种的采收与贮藏方法。     

疑有禽白血病病毒混合感染的肉种鸡大肝大脾病

山东某父母代肉种鸡开产后死淘率突然升高,死亡鸡肝脏、脾脏、腺胃等内脏器官肿大,高峰期周产蛋率仅为72%,明显低于同场区未发病鸡群的83%,更显著低于其标准产蛋率（87%）。利用RT-PCR技术对肿大的脏器分别进行分子病原学诊断,禽网状内皮增生症病毒、戊型肝炎病毒和马立克氏病毒等PCR检测结果阴性,而ALV pol基因检测阳性,经测序与GenBank 已发表的ALV E 亚群毒株的核苷酸同源性高达97.5%-99.5%。血清学检测证实, ALV-AB亚群在发病前阳性率为8.3%,而发病后的抗体阳性率则攀升为70%。鸡群发病后的种蛋蛋清p27抗原检测ALV阳性率为5.3%。综上所述,鸡群可能混合感染ALV。