Lamb wool shedding is a good predictor of ewe wool shedding

Interest in reducing labour costs due to shearing has led to development of breed types that shed their wool naturally. Selection at young ages can facilitate response. Reliability of predictions of adult from lamb wool shedding (WS) is thus key in the design of breeding programmes to increase shedding. Our objectives were to estimate heritabilities and genetic relationships between WS measured once in lambs and repeatedly in ewes and to assess the accuracy of lamb WS EBV to predict ewe WS EBV based on a multi-trait threshold or a repeatability model. Data were 4,971 lamb and 3,335 ewe WS records on a Romanov, White Dorper and Katahdin composite flock. For the multivariate model, WS heritability ranged from 0.47 ± 0.03 in lambs to 0.59 ± 0.04 at 1 year of age. For the repeatability model, WS in adult ewes was moderately heritable (0.50 ± 0.03) and repeatable (0.60 ± 0.02). Genetic correlations were 0.72 ± 0.04, 0.65 ± 0.05, 0.50 ± 0.09 and 0.51 ± 0.09 between lamb WS and 1st through 4th record, respectively. Given the moderately high heritability and high correlations between WS performance in lambs and ewes, selecting animals early in life would effectively increase WS in crossbred flocks.     

Maternal nutrition during pregnancy influences offspring wool production and wool follicle development

The effects of maternal nutrition on offspring wool production (quality and quantity) were evaluated. Primiparous Rambouillet ewes (n = 84) were randomly allocated to 1 of 6 treatments in a 2 × 3 factorial design. Selenium treatment [adequate Se (ASe, 9.5 μg/kg of BW) vs. high Se (HSe, 81.8 μg/kg of BW)] was initiated at breeding, and maternal nutritional intake [control (CON, 100% of requirements) vs. restricted (60% of CON) vs. overfed (140% of CON)] was initiated at d 50 of gestation. Lamb birth weight was recorded at delivery, and all lambs were placed on the same diet immediately after birth to determine the effects of prenatal nutrition on postnatal wool production and follicle development. At 180 ± 2.2 d of age, lambs were necropsied and pelt weights were recorded. Wool samples were collected from the side and britch areas, whereas skin samples were collected from the side of each lamb only. Although Se status did not influence side staple length in males, female lambs born from ewes on the ASe treatment had a shorter staple length (P < 0.05) when compared with females from ewes on the HSe treatment. Maternal nutritional intake and Se status did not influence (P ≥ 0.23) wool characteristics on the britch. However, at the britch, wool from female lambs had a reduced comfort factor (P = 0.01) and a greater (P = 0.02) fiber diameter compared with wool from male lambs. Maternal Se supplementation, maternal nutritional plane, sex of the offspring, or their interactions had no effect (P > 0.13) on primary (29.10 ± 1.40/100 μm(2)) and secondary (529.84 ± 21.57/100 μm(2)) wool follicle numbers. Lambs from ASe ewes had a greater (P = 0.03) secondary:primary wool follicle ratio compared with lambs from HSe ewes (20.93 vs. 18.01 ± 1.00). Despite similar postnatal diets, wool quality was affected by maternal Se status and the maternal nutritional plane.     

青海细毛羊和新疆细毛羊公羊羊毛含硫量测定

运用重量法对三角城种羊场１４只青海细毛羊公羊和８只新疆细毛羊公羊共８８个毛样的含硫量进行测定。结果表明：含硫量水平在２．４０％－３．２４％，在羊毛含量正常值２．７％－４．２％内，偏低；两品种间、各品种不同年龄间及个体不同部位间的羊毛含硫量水平均无显著差异（Ｐ＞０．０５）；在羊毛的不同区段上含硫量水平具有一规律，即中段罗高，顶部软低，底段居中。     

羊驼毛的显微结构

羊驼亦称驼羊,原产于南美洲的安第斯山脉,共同祖先为原柔蹄类动物。羊驼对高海拔和干旱地域有着良好的适应能力。世界上现有羊驼350万只,其中90%以上分布在南美地区,是南美特有的动物品种[1]。羊驼毛品质优良,细长,柔软,具有多种光泽,弹性和韧性极佳,且对人体无过敏刺激,经济价     

Production and oxidation of wool grease after shearing

OBJECTIVE: To measure the production and amount of oxidation of wool grease secreted immediately after shearing. To identify components of wool grease that might act as a carrier to facilitate lateral diffusion of topically applied insecticides. DESIGN: Fine-wool Merino sheep were shorn and residual greasy wool was collected from the sheep's flank. The quantity of grease produced, and the amount of oxidation was measured during 18 days after shearing. Wool grease was fractionated into five component groups based on their polarity and the degree of oxidation in these fractions determined. RESULTS: There was a 24% increase in grease production within 2 days after shearing but secretions returned to pre-shearing amounts after 4 days. During this period wool grease oxidized rapidly. Of the grease fractions examined, sterol and wax esters remained essentially unoxidized whereas free sterols such as cholesterol and lanosterol, fatty acids and polar lipids, aldehydes and alcohols were extensively oxidized within 7 days after shearing. CONCLUSION: The transient increase in grease production after shearing may facilitate diffusion of topically applied synthetic pyrethroid insecticides. Oxidation of grease components may then contain the insecticide and limit further diffusion. Incorporating the insecticide in non-oxidising fractions of wool grease may make insecticide dispersion more efficient.     

影响绵羊羊毛性状的主效基因和QTL

在绵羊中已经发现了许多影响重要经济性状的主效基因,其中包括影响色素沉着、羊毛质量和角蛋白等的主效基因,而角蛋白对羊毛纤维的形态特征有着重要影响 。在羊毛质量和产量性状上,基因图谱研究已经发现了与其变异相联系的染色体区域。现在面临的主要挑战就是建立一种有价值的分子技术方法来提供绵羊的遗传进展。     

The persistence of foot-and-mouth disease virus on wool

SUMMARY Five Suffolk sheep, held in a high-security isolation room, were exposed for 2 hours to the aerosol of 3 mature pigs that had been infected with foot-and-mouth disease virus (FMDV), strain O₁-BFS. The fleeces of 3 of the sheep were contaminated with FMDV at 2 days post exposure (dpe), while at 5 dpe the fleeces of all 5 sheep were more extensively, and more heavily, contaminated. The persistence of FMDV on contaminated wool was examined in vitro using multiple 0.5 g samples of Merino wool that were each contaminated with one of 3 strains of FMDV in tissue-culture medium: O₁-BFS, O-Morocco (O-MOR 9/91) or an Asia 1 strain (TAI 1/90). Wool samples were held at either 4°C, 18°C or 37°C, and decay curves were established for each virus at each temperature. These curves predicted that O₁-BFS, O-MOR 9/91 and TAI 1/90 would fall below detect-able levels at 72, 70 and 48 days post contamination (pc), respectively, for wool stored at 4°C; at 11, 12 and 12 days pc, respectively, for wool stored at 18°C; and at 57, 68 and 33 hours pc, respectively, for wool stored at 37°C. For wool contaminated with O₁-BFS-infected sheep faeces, urine or blood, or with O₁-BFS-infected cattle saliva, decay curves predicted virus to persist for 5 to 11 days pc at 18°C. We demonstrated that the simulated scouring of FMDV-contaminated wool at 60° to 70°C would usually reduce virus to below detectable levels. The detergent component of the scouring process had little, if any, antiviral activity, and scouring at 20°C or 50°C had limited impact on FMDV titres . We recommend that either (1) simple storage of FMDV-contaminated wool for 4 weeks at temperatures of 18°C or higher, or (2) scouring of contaminated wool at 60° to 70°C would be sufficient to remove the threat of FMDV-contaminated wool being infectious to other animals .     

Pesticide use and residues on Queensland wool

Objective To determine practices for control of louse infestation and blowfly strike in Queensland sheep flocks that are associated with organophosphorous and synthetic pyrethroid residues on wool.
Design Information on residues was obtained from a survey of Queensland wool clips. Information on pesticide use was obtained from a trace-back postal survey. The association between pesticide use and residues was assessed using generalised linear models, controlling for potential confounding by flock location.
Procedure Between 1995 and 1997 Queensland wool clips were randomly sampled. Samples were tested for the presence and amount (mg per kg of greasy wool) of organophosphorous and synthetic pyrethroid pesticides. A questionnaire seeking information on flock characteristics and pesticide use was sent to the manager of each flock from which a wool sample was tested.
Results The median amount of OP and SP residue was 0.8 and 0.25 mg/kg, respectively, and 91 and 95% of wool samples contained < 8 mg/kg of OP and SP residues, respectively. The frequency of OP pesticide use for louse control was significantly (P = 0.005) associated with mean OP residue amount, and the timing of SP use for louse control, in relation to shearing, was significantly (P < 0.001) associated with mean SP residue amount.
Conclusion Most Queensland wool clips have acceptable amounts of residues after the use of OP and SP pesticides, but wool growers can further reduce residues by effectively controlling louse infestation with pesticide applications early after shearing and the use of non-chemical methods of ectoparasite control.     

藏羚羊绒纤维特性的研究

本次研究测定了藏羚羊5个部位绒的细度、伸直长度、伸度和强度;观察了绒纤维的皮质细胞和鳞片层的结构;并将藏羚羊绒与辽宁绒山羊、西藏山羊和山东绒山羊所产羊绒进行了比较.藏羚羊体表各部位的绒毛细度、伸度和强度差异显著(P＜0.05);绒纤维的伸直长度在背、肩、体侧和股部差异不显著(P＞0.05),腹部绒的伸直长度与背部、肩部、股部和体侧部差异显著(P＜0.05);绒纤维皮质层细胞呈梭状,纤维的鳞片层呈环形.藏羚羊绒细度极显著低于西藏、四川、辽宁和山东绒山羊(P＜0.01),伸直长度和相对强度与西藏、四川、辽宁、山东和内蒙古绒山羊的绒相比差异显著(P＜0.05);藏羚羊绒伸度显著高于西藏、辽宁、山东绒山羊所产绒(P＜0.05).     

青海半细毛羊毛纤维物理性能分析

青海毛肉兼用半细毛羊毛纤维物理性能测定结果：都兰县、海晏县公、母羊毛纤维56/50支分别占42．00％和27．59％。每平方厘米皮肤面积上毛纤维根数都兰县公、母羊为1820-2401根和1711～2127根，海晏县公、母羊为1986～2593根和2173～2902根。     

甘肃高山细毛羊舍饲养殖试验观察

对传统放牧条件下的甘肃高山细毛羊开展季节性舍饲喂养,结果表明:舍饲组成、幼年母羊和当年羔羊体重比放牧组分别增加12.86、12.47和5.27kg;羊毛长度除当年羔羊两组间基本相等外,舍饲组成、幼年母羊比放牧组分别长1.08cm和1.06cm;舍饲组仔畜成活率、繁殖成活率和成畜保活率分别达到100%、94.90%和100%,比放牧组分别提高5.32、16.83和3.6百分点;舍饲组公母羔羊平均初生重为4.06kg±0.67kg,比放牧组提高26.88%;两组绵羊期末体高、管围变化不大,舍饲组胸围、体斜长比放牧组增长幅度明显;舍饲组各年龄段羊毛产量分别达到5.24、4.61和3.77kg,比放牧组分别提高57.83%、52.15%和39.11%,差异极显著(P<0.01)。