引进专门的肉用白头杜泊绵羊提高肥羔生产效益

中国是一个羊肉生产大国,却不是羊肉生产强国;随着羊肉生产从成羊肉生产转向肥羔肉生产,需要关注和引进专门的肉羊品种;市场的变化,带来生产的变化,品种的更新才能促进生产的发展;选用肥羔生产的终端父本时,由于羔羊产毛方面没有利用价值,所以除了考虑早期产肉方面的效益外,非常有必要考虑适应能力、抗逆性和羊皮方面的效益,使肥羔生产的综合效益得到进一步的提高.     

绵羊肥羔症的防治

绵羊肥羔症也称羔羊肥胖症,是羔羊的一种代谢疾病。本病多发生于一个半月到两个月龄左右的体大肥胖的羔羊。我县东三家子乡某村一养羊户饲养的32只绵羊羔,在1986年3月16日第一次放牧途中有12只体大肥壮的羊羔突然发病,当即死亡5只,经抢救治疗后治愈7只。现将本病发生和抢救治疗情况     

一例黑头杜泊绵羊的剖腹产手术

山东省邹城市城郊畜牧兽医工作站承担了邹科字[2006]23号文件科技发展计划项目,引进黑头杜泊绵羊13只,其中母羊10只,公羊3只,进行纯繁和杂交利用。10只母羊经过同期发情处理,同期交配,于2007年5月15日到了分娩期,9只母羊顺利产羔,其中一只母羊临产前1d便精神萎靡、食欲减退、行     

优质肥羔生产技术

正近几年,我国肉羊生产特别是绵羊肥羔生产发展较快,但与世界养羊业较发达的国家相比,差距依然较大。本文旨在通过探讨影响绵羊肥羔生产的各种因素,提出相应的改进办法和技术措施,为发展我国优质肉羊生产提供科学依据和技术支撑。一、品种与杂交组合利用不同种群杂交产生的后代,在生活力、生长势和生产性能等方面,往往表现出优于其亲本群的现象,称为杂种优势。     

肥羔生产的技术措施

随着科学技术的发展,粗放、原始经营方式的养羊业已明显落后。养羊业,尤其是肥羔生产应转向大规模、工艺先进的工厂化、专业化生产。为了适应新的生产需要,提高经济效益,肥羔生产中应主要采取以下几方面的生产技术措施。     

杜泊绵羊与小尾寒羊杂交肥羔肉质特性的研究

选在相同条件下饲养的杜泊绵羊与小尾寒羊杂交一二代和小尾寒羊共24只,分为3个处理。屠宰取背最长肌和股二头肌测定肌肉中化学成分、氨基酸、矿物质和微量元素含量。结果表明:粗蛋白质含量杜寒F1 20.1%,杜寒F220.3%,均高于小尾寒羊19.6%。17种氨基酸总量为杜寒F1 19.13 g,杜寒F2 19.38 g,小尾寒羊18.42 g。人体营养所需要的必需氨基酸含量分别比小尾寒羊提高2.16%和8.11%;其中蛋氨酸含量显著(P<0.05)高于小尾寒羊。与风味(鲜味)有关的天冬氨酸和谷氨酸含量也分别比小尾寒羊高。杜寒杂交一二代肥羔肉中钙、铁、锰显著高于小尾寒羊(P<0.05)。而小尾寒羊肥羔肉锌、铜含量则显著高于杜寒F1和F2杂交羊。有毒有害元素均未检出。综合评定杜寒杂交一二代肥羔肉的营养价值和肉质品质接近,但均优于小尾寒羊。     

波本杂交一代山羊生产肥羔的试验效果

选择3月龄左右的波本（波尔山羊与渝东白山羊）杂交一代羊20只,采用完全随机化试验设计,分成2个组,进行为期90d的肥育试验,观察波杂一代羊用作肥羔生产的效果。以活体重、胴体重、肌肉颜色、肋肉厚度为考察指标,结果显示肥羔肉等级介于良好级与优等级之间,表明波尔山羊与渝东白山羊杂交一代用作肥羔生产有良好的效果。     

杜泊绵羊与小尾寒羊杂交后代肌肉风味的研究

本研究旨在通过对肌肉氨基酸和脂肪酸的检测,探讨杜泊羊与小尾寒羊杂交对肌肉风味的影响,为选育优质肉羊品种提供理论依据。结果表明：从氨基酸总量来看,杜寒F1较小尾寒羊和杜泊羊分别提高30．06％和0．57％,杜寒F2较小尾寒羊和杜泊羊分别提高29：49％和0．13％;从主要脂肪酸含量来看,杜寒F1较小尾寒羊和杜泊羊分别降低0．29％和10．05％,杜寒F2较小尾寒羊和杜泊羊分别降低13．54％和22．01％;从挥发性脂肪酸来看,杜寒F1较小尾寒羊和杜泊羊分别降低2．93％和6．44％,杜寒F2较小尾寒羊和杜泊羊分别降低21．24％和24．09％。杂交后代杜寒F1和杜寒F2氨基酸含量有所提高,同时能够降低羊肉膻味。     

杜泊羊与小尾寒羊杂交后代屠宰性能和肉品质的研究

本研究旨在通过对屠宰性能、肌肉化学成分的检测,探讨杜泊羊与小尾寒羊杂交对后代屠宰性能及肉品质的影响,为选育优质肉羊品种提供理论依据。结果表明：从屠宰性能来看,杜寒F1和杜寒F2均继承了杜泊羊的优点,对小尾寒羊产肉率低的缺点有较大改善;从总体肉品质来看,杜寒F1和杜寒F2均继承了杜泊羊产肉多、肉质鲜美的优点,并且在肉色、嫩度、熟肉率、滴水损失、含钙量方面均优于小尾寒羊和杜泊羊。杜寒F2的肌肉嫩度、肉色指标均优于杜泊羊、小尾寒羊及F1代。     

Evaluation of the efficiency of alternative two-tier nucleus breeding systems designed to improve meat sheep in Kenya

A deterministic approach was used to genetically and economically evaluate the efficiency of five two‐tier nucleus breeding systems for meat sheep in Kenya. The nucleus breeding systems differed in terms of whether the system was closed or open, in the type of animals that were involved in the movement of genetic superiority and in the number of selection pathways in each system. These systems were compared under four alternative breeding objectives based on monetary genetic gain and profit per ewe. The first objective simulated a situation where the flock size cannot be increased due to non‐feed related constraints (FLOCK). The second specifically assumed that the flock size is restricted due to limited amount of feed resources (FEED). The third and fourth objectives assumed that sheep performed only tangible roles (TR) and both tangible and intangible roles (IR) in the production system respectively. Monetary genetic gains were highest for all objectives in an open nucleus system with a certain proportion of commercial‐born ewes being introduced in the nucleus while at the same time utilizing young rams from the nucleus to breed sires and dams for the nucleus and commercial sector (ONyre). Utilizing young rams in a closed nucleus system for the dissemination of superior genes resulted in higher annual monetary genetic gain than utilization of old rams. Profit per ewe was significantly higher for FLOCK and IR in ONyre. In a closed system that allowed for downward movement of dams from the nucleus to the commercial sector to breed sires and dams, profit per ewe was highest for FEED and TR. The success of a nucleus breeding system should also focus on the profitability and logistics of establishing it. The implication of these results on the choice of two‐tier nucleus breeding systems for the improvement of meat sheep is discussed.     

Economic values for lean meat and fat efficiency in Norwegian Landrace nucleus pig population

A profit function was developed to estimate economic values for new efficiency traits for fattening pigs in Norwegian Landrace. These traits were lean meat efficiency (LME) and fat efficiency (FE). LME and FE described how much feed the animal used to produce 1?kg lean meat and fat as a deviation from the mean. Both traits were derived from analysing total feed consumption in a random regression model which included lean meat and fat content of the carcass (FC) as random covariates. In addition, economic values and breeding values were calculated for days from 40 to 100/120?kg live weight (DAYS), lean meat percentage (LMP) and FC. To compare LME and FE with total feed intake (FI), two indexes were constructed. One index included LME, FE, DAYS, LMP and FC and was referred to as breeding goal A and one index included FI, LMP and DAYS and was referred to as breeding goal B. The standardized economic values for LME and FE were 8.9 and 2.9 EUR/σ_a, respectively. There was a larger variation in the index for breeding goal A (SD?=?5.65) than B (SD?=?3.97). The results suggested that the two efficiency traits had an economic importance in pork production and that there was a potential for increased genetic gain in profit by using breeding goal A compared to breeding goal B.     

Effects of ewe breed and management system on efficiency of lamb production: I. Ewe productivity

Performance of 1/2-Suffolk, 1/2-Rambouillet (Western) and 1/2-Suffolk, 1/4-Rambouillet, 1/4-Finnsheep (1/4-Finn) ewes was compared in three different lamb production systems over 3 yr. System 1 (56 ewes) involved late fall lambing over 84 d. System 2 (51 ewes) involved January and February lambing for 60 d. System 3 (47 ewes) involved March and April lambing for 45 d. Pregnancy rates for yearling ewes were lower in System 1 in yr 1 (50.7% vs 87.4% for Systems 2 and 3) but differed little among systems for older ewes or in remaining years. Average pregnancy rates for 2-yr-old and older ewes were 89.5, 94.0 and 85.7% for Systems 1, 2 and 3, respectively. When the pregnancy rate was adjusted to a 45-d lambing season, means for older ewes were 78.6, 89.5 and 85.7% for System 1, 2 and 3, respectively. Ewe breeds did not differ in their pregnancy rates. Prolificacy (lambs born per ewe lambing) was higher for 1/4-Finn ewes (1.83 +/- .06 vs 1.55 +/- .07) and was higher in System 3 (1.86 +/- .06) than in Systems 1 (1.60 +/- .07) or 2 (1.63 +/- .05). Body weight at breeding in postyearling ewes was less in System 3 (64.3 kg); than in Systems 1 or 2 (average of 73.1 kg). Breeds did not differ in weight at 1 or 2 yr of age, but Western ewes were 2.1 +/- 1.1 kg heavier as 3-yr-olds.(ABSTRACT TRUNCATED AT 250 WORDS)     

Genetic trends for objectively measured and subjectively assessed traits in a Dorper sheep flock

Genetic trends were constructed to monitor the genetic change for subjectively assessed and objectively measured traits using data emanating from complete records from the National Small Stock Improvement Scheme database and performance records accumulated by a single breeder over a period of 24 years. The objectively measured production traits considered were weaning weight, post-weaning weight (PWW), yearling weight, average daily weight gain to weaning (ADGW), average daily weight gain during post-weaning phase (ADGPW) and average daily weight gain up to yearling age. The subjectively assessed traits (scored on a five-point scale) were conformation, fat distribution, size, type and colour. Direct genetic trends for live weight and growth traits (with the exception of ADGPW) were positive. All the objectively measured traits where maternal effects were significant, except PWW, registered small declines in maternal breeding values. The fastest genetic progress was attained by ADGW, which amounted to 0.29 % of the overall phenotypic mean per annum. Conformation and type exhibited positive but slow increments in direct breeding values at an equivalent annual rate amounting to 0.12 and 0.09 % of the overall phenotypic mean, respectively. Size demonstrated a negative genetic trend of ?0.14 % of the overall phenotypic mean per annum. Genetic trends for fat distribution and colour were negligible. It was concluded that breeders should focus more on the performance recording of objective traits as they are likely to respond favourably to selection pressure.     

Results of a crossbreeding experiment with sheep for different systems of fat lamb production. I. Reproductive traits

A crossbreeding experiment with sheep was carried out at two of the University's experimental stations between 1969 and 1973. On farm I ewes of five groups of different first crosses were tested against the indigenous purebred Merinoland sheep for five lambing periods. The ewes were kept under an accelerated lambing programme, the lambs were reared artificially. On farm II the same domestic breed was tested against three first cross lines with spring lambing and ewes suckling their lambs for 5 to 8 weeks. Each test group consisted of at least 50 ewes made up of 10 halfsib groups. 10 rams of each of four exotic fat lamb sire lines were hand-mated to the ewes. In addition, purebred and special control matings were carried out. All ewes in the experiment were of the same age.The data were analyzed by least squares procedures for different reproductive traits (gestation length, litter size for lambs born and reared, litter weight, score for lambing difficulties) and by simple one-way classifications for various others (lambs born and reared per ewe and year, lambing frequency, body weight, fleece weight, wool income).Since no significant interactions among main effects were detected for any trait, the presentation of the results emphasizes the general combining ability of the sire and dam lines. No significant differences were found between sire lines on both farms in all traits except gestation length. For the most important reproductive traits the differences between the dam lines were highly significant, the Finnish Landrace crosses being the best in both lambing frequency and number of lambs per litter. The superiority of these crosses cannot be maintained for the number of lambs reared and slaughtered, if, like in farm II, facilities are not available to rear lambs of large litters without high losses.     

Effect of diet and type of pregnancy on plasma metabolic response in sheep and its further effect on lamb performance

This trial evaluated the individual and interactional effects of diet and type of pregnancy (twin or single) on plasma metabolic response in ewes and their lambs from late pre-partum to late post-partum. Thus, a flock of 18 Ile de France breed sheep, consisting of 8 twin-bearing and 10 single-bearing ewes, were allocated to one of two groups according to their diet, either based on ad libitum naturalized pasture hay (NPH) or red clover hay (RCH), from d 45 pre-partum to d 60 post-partum. Plasma samples were collected at different times to determine albumin, cholesterol, total protein and urea, plus glucose and β-hydroxybutyrate (BHB) concentration in ewes. The data was processed using the lme4 package for R, and SPSS Statistics 23.0 for Windows. The results showed that both diet and type of pregnancy influenced the metabolic profile in ewes, showing an inverse relationship between single- and twin-bearing ewes regarding glucose and especially BHB proportions from pre-partum to birth. During post-partum, higher urea concentrations were observed in twin- and single-bearing ewes fed RCH in contrast to those fed NPH, as a result of the higher-quality forage offered to ewes. Regarding lambs, the diet and type of pregnancy influenced the total protein and urea levels, where an inverse relationship at birth and early post-partum between albumin and cholesterol vs. total protein and urea was detected, reflecting a trend (P value between 0.06 and 0.07) to a better performance by groups of single lambs, especially those from single-bearing ewes fed RCH. Finally, under the conditions of this study, the maternal diet and type of pregnancy influenced the plasma metabolic response in ewes and their lambs, affecting the lamb performance especially at birth.

     

Results of a crossbreedign experiment with sheep for different systems of fat lamb production. II. Growth and carcass traits

At two experimental stations of the University Hohenheim, a crossbreeding experiment with sheep was carried out from 1969 to 1978. Experimental design, material and results for reproductive traits are described in a first communication (Nitter, 1975).A total of 1 168 lambs on farm I and 440 lambs on farm II was weaned early and fattened on concentrates in a controlled housing system. Lambs of the same sex were slaughtered at equal weights. Data were collected for birth weight, growth in different periods, and various traits related to carcass conformation and carcass composition.The data were analyzed by least squares procedures. Interactions among main effects were not detected for any trait.For the important growth traits, the differences between sire lines as well as those between dam lines were rather small. Differences between dam lines were mainly caused by differences in birth weight.Significant differences between the test lines were found for most traits of carcass conformation and composition. The differences between dam lines for fat percentage in the carcass are the most important ones from an economic point of view. As expected, the offspring of the Finncross ewes had the fattest carcasses of all groups when slaughtered at equal weight.If both reproductive traits of the ewes as well as growth and carcass traits of their lambs are considered the results of this experiment show that the economic efficiency of fat lamb production can be significantly increased by substituting the traditional purebreeding production by appropriate systems of commercial crossbreeding.     

肉羊生产转型升级提质增效的“程明模式”

铜川市程明牧业股份有限公司(以下简称“程明牧业”)前身是一位残疾青年于2012年与他人合办的羊场。由于该羊场圈舍简陋、品种繁杂低劣、经营管理粗放而亏损,2013年合伙人撤资。2014年,陕西省畜牧技术推广总站联合铜川市畜牧技术推广站等单位,按照“深入实际搞调研、理清思路作指导、技术支撑提水平、抓好样板做示范”的工作思路助残抓点。在有关部门和单位的支持下,该羊场现已发展为以肉羊养殖为主,集饲草饲料经营、肉羊屠宰加工、品牌销售为一体,融合农业种植、休闲观光、科普文化和餐饮服务等产业的综合性企业,成功走出了一条肉羊转型升级提质增效的路子。