甘南藏羔羊补饲育肥试验

甘南州草原辽阔,草畜资源得天独厚。独特的甘南牦牛、藏羊、河曲马、河曲藏獒等畜种资源是长期以来在甘南草原特定的生态条件下,经过当地藏族群众辛勤选育和长期自然选择形成的适应高寒严酷条件的地方优良     

不同营养水平羔羊育肥效果的试验

随着肉羊饲养成为世界养羊业的主要发展方向,肥羔在世界各国备受重视,我国也加大了肥羔研究工作的力度,各种方式的杂交改良纷纷应用于生产。夏洛莱种羊是义县引进的大型肉用品种。夏洛莱羊与东北细毛羊和小尾寒羊杂交的对比试验情况,使百姓依据实际情况选择最佳组合。     

Performance and effects of small ruminal boluses for the electronic identification of fattening lambs

Two types of electronic boluses were evaluated in two experiments using intensively reared lambs. In Experiment 1, 148 lambs were assigned to three treatments defined by bolus type and lamb's age: mini (M, 5.2 g) applied as early as possible; small (S, 20.0 g) applied after weaning; and control (C), without bolus. Application of the M and S boluses required lambs older than 8 and 46 days, respectively. No differences in total mortality (6.8%), milk and concentrate intakes, and final live weight (LW) were observed between bolus types at the end of fattening (11 weeks). Total retention rates of boluses were 59.0% and 100% for the M and S boluses, respectively. Abattoir retrieval was 100%. Conventional ear tag loss rate in the same period was 2.1%. In Experiment 2, we used 94 lambs in three treatments, 2 of them applied with M boluses at: M1, 1 week before weaning; M2, 1 week after weaning; and C, without bolus. Bolus retention rate (43.5%) of M boluses was not affected by weaning. Ear tag loss rate was 3.2%. In conclusion, application age of M boluses was earlier than 8 days of age but their retention rates need to be improved. The S boluses are feasible to use as a permanent identification system in lambs older than 7 weeks. For earlier tagging, boluses as small as M but with greater weight and specific gravity should be developed.     

Role of magnesium in the aetiology of ovine urolithiasis in fattening store lambs and intensively fattened lambs

High dietary levels of magnesium (greater than 2 g/kg drymatter [DM]) have been implicated as the main causal factor of urinary calculi in concentrate-fed lambs. Experiments were performed to try to reproduce this effect of high magnesium (from added calcined magnesite) on the incidence of urolithiasis in lambs. In the first, store lambs were given diets containing magnesium in the following concentrations: A,2.9; B,8.6 g/km DM. Twenty-four blackface lambs were each allocated to A and B and the control group of 160 lambs was fed a combined dried grass/sugar beet pulp pellet and hay ad libitum (diet C). The animals were housed and fed ad libitum until they were killed at an average liveweight of 35 kg. No animals showed clinical signs of urolithiasis and post mortem only a trace of calculous material was recovered from one lamb fed diet A. In the second experiment housed Suffolk and Suffolk cross lambs were fed a starter beginning at three to four weeks old and changed to a finisher at a liveweight of 23 kg. The feeds were either high magnesium starter (5.7) and finisher (6.0) or low magnesium starter (2.3) and finisher (2.8 g/kg DM). Twenty-two single lambs and 32 twins were assigned to both high and low magnesium diets. Lambs fed additional magnesium drank more water/kg DM intake and one of the single lambs showed clinical signs of urolithiasis and was killed. No others showed clinical signs and from the 62 killed there was no post mortem recovery of calculous material.     

寒冷地区羔羊直接育肥效果及对母羊繁殖率的影响

羔羊直接育肥不但可以使肥羔生产与市场变化充分衔接，还有效地利用了羔羊维持代谢需要最少、生长速度最快的阶段，以最小的投入获得了最大的回报。同时，为生产母羊保持较高繁殖率创造了有利条件，试验结果表明：新疆高寒养羊地区在应用了包括绵羊冷季饲养技术、繁殖技术、羔羊提早断乳技术的基础上，配套以羔羊直接育友有关的饲养和疫病防制技术，羔羊在5月龄出栏，平均活重可达35kg以上，屠宰率达到47.4%，每人羊较秋季育肥多获利76元。同时，羔羊实施直接育肥，提前断乳，生产母羊繁殖率明显提高，有29.26%（84／287）的母羊在夏牧场产羔（当年产第二胎），高于对照组14.26个百分点，较晚春羔母羊4.7％（3／64）高24个百分点，差异显著（P＜0.01）。     

饲粮组成对育肥羔羊肠道微生物菌群结构的影响

为研究饲粮组成改变对育肥羔羊肠道菌群结构及多样性的影响,选择生长发育良好、体重相近的2月龄蒙系公羔羊76只,随机分成2组,每组38只,分别饲喂不同的饲粮,对照组为精料+苜蓿饲粮,处理组为精料+全株玉米青贮+苜蓿+花生秧的全混合饲粮,试验期122 d,其中预试期20 d.试验结束后,每组随机选取4只羔羊屠宰并采集小肠及盲...     

湖羊与澳湖F1代羔羊短期育肥效果的比较

本研究以湖羊和澳湖F1代羔羊(澳洲白绵羊♂ × 湖羊♀)为研究对象,对其生长性能、屠宰性能、体组成和肌肉品质进行比较分析,综合评估湖羊与澳湖F1代羔羊育肥效果.随机选择湖羊和澳湖杂交F1代羔羊各61只,在相同的饲养环境和日粮下进行育肥和性能测定.饲养试验结束后立即屠宰,对试验羊只的生长性能、屠宰性能、体组成和肌肉品质等指标进行系统测定和比较.结果显示,湖羊和澳湖F1羔羊育肥期初始体重(0 d)、末期体重(60 d)无显著差异(P>0.05),全期平均日增重(ADG)、平均日采食量(ADFI)无显著差异(P>0.05),但在育肥前期(0～20 d)湖羊的ADG极显著高于澳湖F1代羔羊(P<0.01),而在育肥中期(20～40 d)和后期(40～60 d)澳湖F1代羔羊的ADG均显著高于湖羊(P<0.05).澳湖F1代羔羊的胴体胸围、臀围和眼肌面积显著大于湖羊(P<0.05).澳湖F1代羔羊的心脏重、肝脏重、肺脏重及其相对重(宰前活重)均极显著高于湖羊(P<0.01),但皮毛重、肾周脂重、肠系膜重、尾脂重及其相对重(宰前活重)均极显著低于湖羊羔羊(P<0.01).湖羊的熟肉率和屠宰结束后45 min肌肉pH极显著大于澳湖F1代羔羊(P<0.01),但澳湖F1代羔羊肌肉失水率、屠宰结束后24 h肉色b*2值和l*2值极显著优于湖羊(P<0.05).总体上来看,湖羊早期生长发育较快,但澳湖F1代羔羊后期生长潜力较大,且胴体性能优于湖羊,胴体脂肪沉积比湖羊少,肉用性能明显提高.     

不同肉羊品种杂交一代羔羊育肥效果

选杜本F1、德本F1、特本F1以及本地绵羊(系蒙古粗毛羊)各7只,共28只,按体重对等的原则分成4组,公4只,母3只,研究同一营养水平条件下,不同杂交组合羔羊的育肥效果,以及对其产肉力及肉品质的影响.结果表明杜本、德本和特本F1的平均日增重分别为210.87、208.18和225.82 g,分别比本地绵羊提高21.74%、20.19%和30.37%(P＜0.05),其中杜本F1和德本F1的增重效果接近;杜本F1在屠宰率和净肉率上分别比本地绵羊高3.86百分点和4.24百分点;骨肉比、眼肌面积和GR值也以杜本F1效果最好.     

Protective effect of vaccination against experimental adenoviral pneumoenteritis in fattening lambs

The protective value of monovalent and bivalent adenovirus vaccines against pneumoenteritis was studied in fattening lambs. The monovalent vaccine was prepared from strain ORT/111 which is a sheep isolate, related to bovine adenovirus type 2. The bivalent vaccine contained virus strains ORT/111 and GY/14, which is a local isolate of ovine adenovirus type 1. After administration of monovalent vaccine higher titres of neutralizing antibodies (1:128–1:512) were found than after the bivalent vaccine (1:16–1:128).Following challenge with a homologous virus strain, the lambs vaccinated with monovalent vaccine remained healthy and did not shed the virus. Those vaccinated with the bivalent vaccine and challenged with GY/14 strain also remained healthy, but two out of five lambs shed virus in the faeces. Non-vaccinated challenged controls developed characteristic signs of the disease and shed the virus both in the nasal discharge and the faeces. From the results it can be concluded that experimental adenoviral pneumoenteritis of fattening lambs can be prevented by active immunization.     

不同组合的全饲粮颗粒饲料肥育羔羊的效果—Ⅱ．产肉力、肉质和肉营养成分分析

按同质原则将40只无角陶塞特(♂)与藏羊(♀)的杂交一代(4～4.5月龄)分为4个饲粮处理组，采用3因子(2×2×2)设计，研究了同一营养水平和在精料为主类型饲粮中，改变部分能量饲料(A因子)和蛋白质饲料(B因子)育肥公羔和羯羔(C因子)的效果。结果表明，A、B因子及其交互作用和A、B、C因子的交互作用对羔羊产肉力和肉质的影响均不显著(P＞0.05)。A、B、C因子及其交互作用对羔羊股二头肌和背最长肌干物质、粗脂肪和粗蛋白含量的影响均不显著(P＞0.05)。公羔的屠宰率显著低于羯羔(P＜0.05)，骨重和肉的pH值显著高于羯羔(P＜0.05)。     

不同营养水平全饲粮颗粒饲料肥育羔羊的效果——产肉力和肉质分析

按同质原则将27只无角陶塞特（♂）与藏羊（♀）的杂交一代公羔（3．5－4月龄）分为3个饲粮处理组，每组9只。采用单因子设计，研究不同营养水平（不同精粗比）全饲粮颗粒饲料对羔羊的育肥效果。结果表明，B组（NRC水平的90％）羔羊胴体重和净肉重显著（P＜0．05）高于C组（NRC水平的80％），有高于A组（NRC水平）的倾向；各组羔羊的肉质无明显差异（P＞0．05）；B组饲粮对羔羊的综合育肥效果最佳。     

Behaviour and welfare of fattening lambs supplemented with varying sizes and types of straw

The aim was to evaluate the effect of size (long or chopped wheat straw), type (barley or wheat) and presence/absence (1 week) of straw supplementation on behaviour and welfare of fattening lambs. Sixteen lambs (65 days) were individually housed to be used in two simultaneous experiments (8 lambs each) for 5 weeks of fattening. After a habituation period, they were offered straw that differed either in size (Experiment 1) or type (Experiment 2), which was followed by a week without straw and then reallocation of straw. Maintenance behaviours, play and stereotypies were analysed using video recording. Physiological stress responses were measured using blood samples taken at the end of the week without straw and after the reallocation of the straw. A preference test was performed during the last week. Concentrate and roughage consumption, average daily gain and conversion index were estimated. Lambs provided with long straw spent more time eating forage, playing and performed fewer stereotypies (Experiment 1). Lambs given wheat straw increased their play behaviour compared with those given barley straw, without affecting stereotypies (Experiment 2). When the straw was removed, lambs performed more behaviours associated with stress; however, this was not reflected in blood stress indicators. Lambs clearly preferred long straw over chopped straw, but no clear preference was observed between wheat and barley straw. The amount of forage intake was consistent with the time spent eating forage, but the amount of concentrate intake did not vary with eating concentrate behaviour, since the amount of concentrate intake was higher when the straw was removed, especially in Experiment 2. Our results show that size more than type of straw supplement impact the behaviour of lambs. Long straw reduces the stereotypies and increases play. This may improve the welfare and performance of fattening lambs, adding ethical value to a highly appreciated product.     

辽宁绒山羊羔羊肉用性能和羊肉品质研究

本研究选择24只辽宁绒山羊羔羊,年龄90±3.5日龄,体重15±0.62 kg,公母各半。试验动物分成3组,1组为高能低蛋白组,饲喂1号日粮;2组为高能高蛋白组,饲喂2号日粮;3组为对照组,饲喂3号日粮。连续试验5个月,每月测量体重1次、屠宰1次,研究体增重、屠宰性能和肉品质指标。结果表明,试验1组和2组日增重均高于对照组,其最高峰分别在第4月龄和第5月龄出现,而对照组则在第3月龄出现。各组育肥后羊绒细度均无显著变化。试验1、2组屠宰率、净肉率、眼肌面积均高于对照组,其中2组与对照组差异显著（P＜0.05）。试验1组和2组肾周脂肪重均高于对照组,其肾周脂肪占胴体重比例高于对照组。试验1、2组GR值高于对照组,差异不显著（P＞0.05）。试验1、2组的嫩度值高于对照组;各组的肉色、失水率和熟肉率均差异不显著（P＞0.05）;对照组失水率低于试验1、2组;对照组熟肉率低于试验1、2组,但差异不显著（P＞0.05）。     

Vinasse added to the concentrate for fattening lambs: intake, animal performance, and carcass and meat characteristics

Twenty-four Merino lambs (mean BW 15.4 ± 0.13 kg, 6 to 7 wk old) were used to study the effects of the addition of 0 (control), 100 (V10), and 200 (V20) g of vinasse per kilgram of concentrate on intake, animal performance, biochemical blood profile, and carcass and meat characteristics. Lambs were assigned to 1 of 3 experimental diets and fed barley straw and the corresponding concentrate ad libitum. When the animals reached 25 kg of BW, a sample of blood was taken and the lambs were slaughtered. Feed intake, growth rate, biochemical blood profile, and carcass and meat characteristics were assessed. Lambs that received the concentrates with vinasse showed a reduced concentrate intake (linear contrast, P = 0.029) and ADG (linear contrast, P = 0.004) and an increased length of fattening period (linear contrast, P = 0.002) as well as feed:gain ratio (linear contrast P = 0.011). Vinasse enhanced ruminal pH (orthogonal contrast control vs. V10 + V20; P = 0.007). Plasma glucose concentrations declined in lambs fed vinasse (linear contrast, P = 0.003), whereas plasma urea concentration increased in animals fed vinasse (linear contrast, P = 0.036). The plasma concentrations of creatinine, triglycerides, and lactate and the enzyme profile studied (alkaline phosphate, alanine transaminase, glutamate oxal-acetate transaminase, γ-glutamyl transpeptidase, and lactate dehydrogenase) were not modified in response to vinasse inclusion. Lambs in the vinasse groups had less Na(+) and nitrate and greater K(+) and nitrite plasma concentrations (linear contrasts, P < 0.05). None of the carcass characteristics studied was affected by vinasse (P > 0.10). Meat chemical composition and characteristics were unaffected (P > 0.10), but shear force was greater for lambs that received vinasse (orthogonal contrast, control vs. V10 + V20, P = 0.007). The addition of 100 or 200 g vinasse/kg of concentrate for fattening lambs reduced feed intake and growth rate and increased the feed:gain ratio and meat toughness without affecting any other carcass and meat characteristics.     

Spineless cactus as a replacement for sugarcane in the diets of finishing lambs

The effects of replacement of sugarcane by spineless cactus (0, 33, 66, and 100 % on dry matter (DM) basis) were evaluated on intake, digestibility of nutrients, ingestive behavior, and performance of finishing lambs. Thirty-six non-castrated Santa Ines lambs at 4 months of age and an initial body weight of 22?±?2.3 kg were assigned in a randomized block design. A quadratic effect was found for intake of DM, organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), and digestible organic matter (DOM), with maximum values of 1.31, 1.19, 0.219, 0.358, and 0.845 g/day estimated with 42.5, 38.5, 38.8, 21.3, and 44.9 % replacement level, respectively. The digestibility of DM, OM, CP, and EE increased linearly; however, there was a quadratic effect on NDF digestibility with maximum value estimated of 500 g/kg with 64.2 % replacement level. Rumination time, total chewing, and rumination efficiency decreased linearly with the replacement levels; however, idle time increased linearly. A quadratic effect was found for final weight, body weight gain, and total weight gain with maximum values estimated of 38.6 kg, 0.232 kg/day, and 16.2 kg with 39.1, 38.2, and 40.4 % replacing levels. The replacement of 49.5 % sugarcane by spineless cactus can be recommended as optimal level, and problems related to intake, digestibility, and performance are concentrated outside that level.     

Effects of feeding different levels of corn steep liquor on the performance of fattening lambs

This study was conducted to assess the effect of feeding corn steep liquor (CSL) on in vivo digestibility, ruminal pH, ammonia and hydrolytic enzyme activities, blood metabolites, feed intake (FI) and growth performance in fattening lambs. The CSL is a by‐product of wet milling process of maize starch industry. The crude protein (CP), rumen‐degradable protein (RDP), lactic acid and metabolisable energy contents of this by‐product were 420, 324, 200 g/kg dry matter (DM) and 12.6 MJ/kg DM respectively. Twenty‐seven male Moghani lambs were assigned randomly into three groups of nine lambs each in a completely randomised design. Three iso‐energetic and iso‐nitrogenous diets containing different levels (0, 50 or 100 g/kg dry matter) of CSL were offered ad libitum three times a day. Forage to concentrate ratio of the diets was 30:70. With inclusion of CSL in diet, the contents of canola meal, fish meal, wheat bran, corn grain and sugar beet pulp were decreased. The contents of DM, ash‐free neutral detergent fibre (NDFom), ether extract, starch, Ca and S were numerically lower, but soluble protein, RDP and non‐fibre carbohydrates were greater in the diets containing CSL in comparison with the control diet. The lambs fed with the diets containing CSL had lower [linear (L), p < 0.06] digestibility coefficients of DM and NDFom as compared to those fed with the diet free of CSL. Ruminal ammonia‐N concentration increased (L, p < 0.05), but pH decreased (L, p < 0.05) with raising CSL level in diet. Carboxymethyl cellulase and filter paper‐degrading activities decreased (L, p < 0.05), while proteases activity increased (L, p < 0.05) as dietary rates of CSL increased. Microcrystalline cellulase and ɑ‐amylase activities were similar among the treatments. Within blood metabolites, only urea‐N concentration increased (L, p < 0.05) in the lambs receiving CSL as compared to those fed with diet without CSL. Dietary inclusion of CSL resulted in linear decreases (L, p < 0.05) in the intakes of DM, organic matter, CP, NDFom and ash‐free acid detergent fibre, and average daily gain. However, the feed conversion ratio was similar among the experimental animals. Overall, feeding CSL up to 100 g/kg diet DM in lamb resulted in reductions of rumen fibrolytic microbial enzyme activities, in vivo digestibility, FI and growth performance, but rumen proteases activity increased.     

Determining the optimal age for recording the retinal vascular pattern image of lambs

Newborn Ripollesa lambs (n = 143) were used to assess the optimal age at which the vascular pattern of the retina can be used as a reference for identification and traceability. Retinal images from both eyes were recorded from birth to yearling (d 1, 8, 30, 82, 180, and 388 of age) in duplicate (2,534 images) using a digital camera specially designed for livestock (Optibrand, Fort Collins, CO). Intra- and inter-age image comparisons (9,316 pairs of images) were carried out, and matching score (MS) was used as the exclusion criterion of lamb identity (MS <70). Retinal images were used for verifying the identity of live lambs of 4 Spanish commercial categories: milk-fed lambs (MF; "lechal," 1 mo of age and <12 kg of BW, n = 136); light fattened lambs (LF; "recental," 3 mo of age and ~25 kg of BW, n = 134); recruited replacement lambs (RR; "ovino mayor," 6 mo of age and ~35 kg of BW, n = 59); and yearling replacement lambs (YR; >12 mo of age and ~50 kg of BW, n = 25). Values of MS were treated with a model based on the 1-inflated bivariate beta distribution, and treated data were compared by using a likelihood ratio test. Intra-age image comparisons showed that average MS and percentage of images with MS ≥70 increased (P < 0.05) with lamb age from d 1 to 82 (81.0 ± 1.0 to 95.9 ± 0.4, and 75.8 to 100%, respectively) and reached a plateau thereafter. Inter-age retinal image comparisons for MF lambs at 30 d showed that the percentage of images with MS ≥70 was greater when reference images at 8 d were used instead of 1-d images (94.8 vs. 87.4%, respectively; P < 0.05). In LF lambs, 30-d retinal images matched better than those at 8 d of age (99.6 vs. 93.6%, respectively; P < 0.05). Regarding RR and YR lambs, the 82-d images allowed the confirmation of 100% lamb identity, whereas 8-d images showed a smaller (P < 0.05) percentage of matching (87.9 and 89.8%, respectively, for RR and YR lambs; P > 0.05); no differences were detected for 30-d images (97.4 and 98.0%, respectively, for RR and YR lambs; P > 0.05). Total percentage of matching was achieved when images were obtained from older lambs (180 and 388 d). In conclusion, retinal imaging was a useful tool for verifying the identity and auditing the traceability of live lambs from suckling to yearling. Matching scores were satisfactory when the reference retinal images were obtained from 1-mo-old or older lambs.     

Shearing male lambs in the cold season improves the carcass yield without affecting fattening performance

This research was carried out to determine the effects of shearing of different genotypes of male lambs (one from pure Karayaka stock and two from its crossbreed) in winter on bodyweight gain, feed consumtion, feed conversion efficiency, rectal temperature and carcass yield. A total of 21 lambs aged 8 months were allocated randomly to experimental groups according to a 2 × 3 factorial arrangement for shorn and unshorn animals. The lambs were fed grass hay (100 g/lamb/day) and commercial concentrate feed ad libitum during a 54‐day of fattening period. The lambs were shorn in the middle of the experiment (27 days after beginning the trial). The interaction between the shearing treatment × genotype of the studied parameters was found to be insignificant. The shearing process increased the rectal temperature (P < 0.01), hot carcass yield (P < 0.05) and dressing percentage (P < 0.05) and decreased the weight of the edible inner organs (P < 0.01). Some of these parameters were affected by the genotypes. It was concluded that shearing male lambs in the winter can have a beneficial effect on the hot carcass weight and dressing percentage without affecting fattening performance, and the performance of Karayaka lambs and its crossbred male lambs were similar under the conditions of the present study.