Energy expenditure in Awassi sheep grazing wheat stubble in the northern Negev Desert of Israel

In semi-arid Mediterranean areas, small grain aftermath stubble represents an important summer source of food for grazing flocks of small ruminants. Wheat stubble is a mediocre source of forage and flocks are grazed in summer under harsh conditions of temperature and air dustiness. However, stubble grazing procedures are changing, water and shading are more frequently available between grazing sessions (“improved management”), and the biological soundness of this ancestral practice needs to be re-visited. The present study was aimed at evaluating the cost in energy of “improved” wheat stubble grazing, compared with feeding a similar diet indoors. The intake of stubble was first quantitatively and qualitatively evaluated in Awassi sheep. Ewes consumed daily 980 ± 100 g day^− 1 of wheat stubble. Ewes were then housed and fed diets consisting of wheat hay, straw and grain formulated to be iso-energetic and iso-nitrogenous to diets consumed from wheat stubble. The average intake of ME was similar during the confinement and the pasture periods (6.4 ± 0.5 and 7.6 ± 0.8 MJ day^− 1of ME, respectively). During 2 days of each period, animals were fitted with external electrodes and data loggers of heart rate and skin temperature. Energy expenditure (EE) was calculated from oxygen consumption estimated as the product of heart beats rate measured for the two days by the amount of oxygen delivered to body tissues at each heart beat (O₂ pulse). The O₂ pulse was determined by simultaneously measurement of oxygen consumption and HR twice daily on two occasions, while grazing stubble and indoors. Energy expenditure and energy balance were not different in sheep while grazing wheat stubble (11.1 and − 3.5 MJ day^− 1) or fed indoors (11.1 and − 4.8 MJ day^− 1). Our data show that stubble did not cover nitrogen and energy requirements for maintenance, and that the cost of summer stubble grazing carried out under conditions described here is less than thought before.     

Effects of Cage Location and Tier Level with Respect to Light Intensity in Semiconfined Housing on Egg Production and Quality During the Late Laying Period

This experiment was conducted to determine the effects of cage location and tier level with respect to light intensity on egg production and egg quality of hens housed in a semiconfined facility. Hens (ISA Brown, n = 225) at 75 wk of age were placed into 3-tier cages as top (T), middle (M), and bottom (B) tiers located in cages illuminated artificially (EI), by window (FW), or between corridors (C) for 2 mo. Light intensity was measured monthly for each cage at 5 cm from feeders every 6 h. Egg production was recorded daily and egg quality was assessed biweekly. Light intensity was the greatest for cages in the FW group (151.9, 119.8, and 89.8 lx for tiers T, M, and B, respectively), followed by EI (52.6, 54.5, and 51.0 lx for tiers T, M, and B, respectively), and C (44.5, 23.4, and 4.7 lx for tiers T, M, and B, respectively). Hens at location EI had greater egg production than hens at FW and C. Egg production for hens at tier T was also greater than for hens at tiers M and B. Egg production for hens at EI and C decreased quadratically, whereas that for hens at FW decreased linearly from tiers T to B. Cage location, but not tier level, affected egg weight. Hens at EI and FW produced heavier eggs than hens at C. Shape index, yolk color, and yolk index were independent of cage location and tier level. Hens at EI and FW produced eggs with thinner and weaker shells than hens at C. Moreover, eggshell strength increased linearly from tier T to B. Both albumen index and Haugh unit were the greatest for hens at FW, followed by EI and C. Their responses to cage location varied with tier levels. In conclusion, variation in light intensity in multitier cage systems in semiconfined laying hen houses may be a contributing factor for depressed laying performance and egg quality.     

高钙日粮对蛋鸡生产性能及出壳雏体内锌含量的影响

生长期日粮钙>3.11%,可使蛋鸡性成熟期明显延缓,开产日龄推迟;其蛋锌及子代出壳雏血锌和多数组织锌含量明显降低,但胚胎及出壳雏鸡未见畸变.出壳雏血锌含量能反映体内锌状态,可作为其评价指标.产蛋期高钙(6.11%)或低钙(0.83%)日粮均可使产蛋性能及孵化率降低.     

冰鲜鸡生产链中沙门氏菌的分离鉴定及PFGE分型研究

为揭示冰鲜鸡生产链中沙门氏菌的分布及传播机制,本研究于2013年7月～2013年12月采集广东某大型一体化养鸡企业下属2个种鸡场、2个孵化场、2个肉鸡场、1个屠宰场和5个销售点样品,用常规法和PCR进行沙门氏菌的分离鉴定,并对分离出的沙门氏菌进行血清学鉴定和PFGE分子分型.种鸡场、肉鸡场、屠宰场和销售点的沙门氏菌的检出率分别为1.46%(7/480)、7.00%(21/300)、62.86%(22/35)和54.67%(41/75),孵化场雏鸡胎粪检出率为1.11%(2/180),死胚检出率为12.00%(9/75).屠宰和销售环节是沙门氏菌污染的重要环节,食品安全风险较高.102株沙门氏菌共产生24种不同的PFGE谱型,从不同环节分离到多组相似度为100%的沙门氏菌,表明冰鲜鸡生产链中存在沙门氏菌沿生产链传播的现象.     

控光增绒技术在辽宁绒山羊中应用效果观察

2010～2012年,辽宁省畜牧科学研究院先后在本院科技示范场、凤城市绒山羊养殖户,开展了辽宁绒山羊控光增绒试验,设置了不同控光时间的试验组以及相应的对照组,以期验证该项技术在辽宁地区和辽宁绒山羊生产中的应用效果。试验结果表明,该项技术对辽宁绒山羊增绒效果不明显,达不到一年两次剪绒、提高产绒量的目的,建议谨慎将该项技术应用于辽宁地区辽宁绒山羊生产中。     

Factors affecting plasma prolactin concentrations throughout gestation in high producing dairy cows

The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod, season, milk production, Neospora caninum-seropositivity, twin pregnancy, and plasma concentrations of pregnancy associated glycoproteins-1 (PAG-1), progesterone and cortisol. Pregnancy was diagnosed by trans-rectal ultrasonography on Day 40 post-insemination and by palpation per rectum on Days 90, 120, 150, 180 and 210 or until abortion in aborting cows. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The study population was comprised of 73 non-aborting (54 Neospora-seropositive cows) and 20 aborting cows (all Neospora-seropositive) cows. In non-aborting cows, GLM repeated measures of analysis of variance revealed that lactation number and days in milk had no effect on plasma prolactin concentrations throughout gestation, whereas high plasma prolactin concentrations were significantly associated with high plasma levels of cortisol and PAG-1, with Neospora-seropositivity, positive photoperiod (increasing day length), twin pregnancy, and with low plasma progesterone concentrations. An interaction among plasma prolactin, plasma cortisol and milk production was observed in that plasma prolactin concentrations differed significantly throughout gestation and were highest in high-producing cows with high cortisol levels. In Neospora-seropositive non-aborting versus aborting cows, mean prolactin concentrations failed to differ on Days 40, 90, 120, 150 and 180 of pregnancy, whereas prolactin values were significantly lower (P = 0.03) in aborting animals on Day 210 of pregnancy. Our results indicate that a positive photoperiod and Neospora-infection lead to increased plasma prolactin concentrations throughout gestation. Reduced prolactin concentrations detected in Neospora-seropositive aborting cows compared to non-aborting animals suggests a protective effect of prolactin in N. caninum infection.     

青海肉羊业生产现状及发展对策

针对国内外及青海省肉羊业生产现状和发展趋势,分析了青海省发展肉羊业的有利条件和存在的问题,并从加强对发展肉羊业的组织领导、建立肉羊良种繁育体系、大力开展经济杂交,实现商品肉羊杂交化、组织肥羔生产、加快畜群周转、加大草原建设和饲草料基地建设、培育“龙头企业”、注重肉羊生产加工环节的无公害化、落实疫病虫防治检疫制度等方面,对发展青海肉羊业生产提出了对策。     

饲粮中添加不同生物制剂对杜寒杂交肉羊生产性能和屠宰性能的影响

本试验旨在比较饲粮添加不同生物制剂对杜寒杂交肉羊生产性能、屠宰性能、组织器官发育及肉品质的影响。采用单因素试验设计,选取平均体重约为32 kg的杜寒杂交F1代肉羊160只,随机分为5组,每组4个重复,每个重复8只。对照组采用基础饲粮,试验组分别添加21 mg/kg莫能菌素、4×109CFU/kg地衣芽孢杆菌、3.2×109CFU/kg酿酒酵母菌、1.1 g/kg复合生物制剂(地衣芽孢杆菌≥6×109CFU/g、酿酒酵母菌≥4×109CFU/g、碱性蛋白酶≥1 000 U/g)。预试期10 d,正试期56 d,每2 d记录1次采食量,每20 d进行1次称重,当复合生物制剂组羊只的平均体重达到约50 kg时,每组选取10只羊进行屠宰,测定其屠宰性能、组织器官重量和肉品质指标。结果表明:1)复合生物制剂组平均日增重、屠宰率显著高于对照组(P0.05);地衣芽孢杆菌组和复合生物制剂组料重比显著低于对照组(P0.05)。2)地衣芽孢杆菌组、酿酒酵母菌组、复合生物制剂组复胃重量均显著高于对照组(P0.05),复合生物制剂组复胃重量占宰前活重比例显著高于对照组和莫能菌素组(P0.05);地衣芽孢杆菌组、酿酒酵母菌组、复合生物制剂组小肠重量及其占宰前活重比例均显著高于对照组、莫能菌素组(P0.05)。3)酿酒酵母菌组肾脏重量占宰前活重比例显著高于对照组(P0.05),其他内脏器官重量占宰前活重比例在各组间无显著差异(P0.05)。4)各组肉品质指标差异不显著(P0.05)。综合得出,从作为饲料添加剂对肉羊生产性能作用效果来看,地衣芽孢杆菌、酿酒酵母菌、复合生物制剂可以替代莫能菌素,地衣芽孢杆菌好于酿酒酵母菌,复合生物制剂最佳。     

乌拉盖牧场草原畜牧业生产系统诊断

本文运用系统工程的理论和方法，对国营乌拉盖牧场的自然环境和社会环境条件进行辩识与分析，找出资源的优势与劣势，以及各种社会经济条件及其组合的影响程度和作用方式。运用诊断模型对畜牧业生产现状进行系统诊断，找出19个病因，从中发现制约该场草原畜牧业生产的终极原因、解决办法和起动因子。通过会诊和检测，运用数学的方法再现科学技术与政策对一个地区或企业的极端重要性，揭示了资本的输入对贫困落后的地区或企业所能起到的重要作用和影响程度。     

已形成产业化格局的苍溪毛兔业

苍溪县近年来抓住毛兔产业西移的契机 ,采取增投入、普科技、抓饲料、建市场、扶龙头、强领导等措施大力发展长毛兔。一个市场牵龙头 ,龙头连基地 ,基地带农户的大产业 ,大规模 ,大流通 ,大市场 ,大效益的毛兔产业化发展格局已基本形成。 1 999年底 ,全县存栏毛兔 2 0 1 5万只 ,产毛 95 8吨 ,兔业产值达 1 6亿元 ,占牧业总产值的 2 9 4 % ,兔业创税 1 0 0 0余万元。通过养兔 ,全县已有 8 5万余农户摆脱贫困 ,走上了富裕之路