Three-dimensional spinal motion and risk of low back injury during sheep shearing

Sheep shearers are known to work in sustained flexed postures and have a high prevalence of low back pain (LBP). As sustained posture and spinal movement asymmetry under substantial loads are known risk factors for back injury our aim was to describe the 3D spinal movement of shearers while working. We hypothesised that thoraco-lumbar and lumbo-sacral movement would be tri-axial, asymmetric, and task specific. Sufficient retro-reflective markers were placed on the trunk of 12 shearers to define thoraco-lumbar and lumbo-sacral 3D motion during three tasks. Thoraco-lumbar movement consistently involved flexion, left lateral flexion, and right rotation. Lumbo-sacral movement consistently involved right lateral flexion in flexion with minimal rotation. Shearers therefore work in sustained spinal flexion where concurrent, asymmetric spinal movements into both lateral flexion and rotation occur. These asymmetric movements combined with repetitive loading may be risk factors leading to the high incidence of LBP in this occupational group.     

Intensive sheep and beef production from pasture — A New Zealand perspective of concerns,opportunities and challenges

This paper details current production trends for sheep and beef cattle production in New Zealand and gives some insight into the opportunities for improvement based on New Zealand research at Massey University. Further it outlines some of the challenges the industries face in the near future. The New Zealand climate favours pasture growth and this is the key to sheep and beef cattle production with over 95% of the diet being grazed pasture or crop. Exports are the focus of the industry with 95% of sheep meat and wool, and 80% of beef exported. There have been considerable gains in production over the last 20 years but there still remains a huge opportunity for further intensification through breeding sheep at an earlier age, increasing the weight of lambs weaned per ewe per year and improving beef production systems. These improvements need to occur within a framework of minimal environmental footprint and produce products that are in demand in the high end international markets.     

The influence of breed on the organoleptic characteristics of Zamorano sheep’s raw milk cheese and its assessment by instrumental analysis

The aim of this study was to investigate the effects of three different somatic cell count (SCC) values on the sensory characteristics of sheep’s milk cheeses from the Castellana and Churra breeds (allowed for Protected Designation of Origin Zamorano cheese manufacture) and the Assaf breed (foreign), determined by typical consumers and instrumentally. The results show that the sensory characteristics of hardness, intensity of taste, and pungency reflect a significant influence of the SCCs of the original milk whereas breed significantly affects colour intensity and hardness (Warner‐Bratzler maximum shear force; WBSF). The instrumental parameters most closely related to the assessments of the typical consumers were WBSF and the value of a*, for hardness and colour respectively.     

Secondary proteolysis in Serra cheese during ripening and throughout the cheese-making season

 Experimental Serra cheeses were manufactured from raw ewe’s milk and thistle flowers following a two-way factorial design. The content of nitrogen soluble in water (WSN), in 2% trichloroacetic acid (2% TCA-N), in 12% TCA (TCA-N) and in 5% phosphotungstic acid (5% PTA-N), and the pH and salt-in-moisture concentration were measured throughout the ripening period (sampling at 0, 7, 21 and 35 days) and the cheese-making season (sampling in November, February and May). Proteolysis in 35-day-old Serra cheese was quantitatively high [average values of 34.6% and 11.9% for WSN/TN (total nitrogen) and 2% TCA-N/TN, respectively], but qualitatively low (average values of 5.8% and 1.2% for 12% TCA-N/TN and 5% PTA-N/TN, respectively). The ratios WSN/TN and 2% TCA-N/TN were lowest for cheeses ripened in February, whereas the ratio 12% TCA-N/TN was highest for cheeses ripened in November. By 35 days of ripening, the average pH and salt-in-moisture concentration values were 5.2 and 4.8%, respectively. No correlation was found to occur between the measured pH or salt-in-moisture concentration and the values of soluble nitrogen fractions throughout the cheese-making season. Received: 14 February 1996/Revised version: 4 June 1996     

羊肉中氯霉素残留检测HPLC法的改进

对羊肉中氯霉素残留的检测方法进行了改进,5g样品用4%氯化钠水溶液乙腈（1∶1）提取2次,每次10ml,合并提取液并用15ml正己烷脱脂,除去正己烷层,剩余液体用乙酸乙酯反萃取2次,每次10ml,分离出乙酸乙酯层并于50℃减压蒸干。残留物用流动相溶解,用高效液相色谱仪于278nm波长处测定,紫外检测器检测。本方法平均回收率为84.3±5.3%,当氯霉素浓度在50～2000ng/ml时,检测呈线性关系,检测限为3.5μg/kg。     

Preparation and functional properties of protein coprecipitate from sheep milk

The optimum conditions for the production of coprecipitate from sheep milk were studied. The best percentage of calcium chloride added to milk was 0.2%, which resulted in a recovery of 97.5% of milk proteins. At low pH (4.5–5), the recovery of protein was low, but it increased at higher pH values (5.5–6.5); recovery was greatest at pH 6.5. The optimum heating temperature to obtain coprecipitate from sheep milk was 85–95°C. The functional properties of the sheep milk coprecipitate were studied. At pH values higher than 6, there were no differences between the solubility of sheep milk coprecipitate and sheep milk sodium caseinate, but the solubility of coprecipitate at pH values lower than 5 was relatively higher than those of the caseinate. At pH ≥6, the emulsion activity index (EAI) for emulsions of sheep milk coprecipitate and caseinate increased as pH increased; at all pH values, the EAI of the coprecipitate was higher than that of the caseinate. Sheep milk coprecipitate showed higher foaming ability and stability than sheep milk sodium caseinate.     

Increased Prostaglandin Response to Oxytocin in Ewes Fed a Diet High in Omega-6 Polyunsaturated Fatty Acids

Diets high in omega-6 polyunsaturated fatty acids (n-6) are associated with increased prostaglandin F_2α (PGF_2α) synthesis in cattle, however, the specific effects on the potential prostaglandin response to an oxytocin challenge in sheep have not been reported. The aim of the current study was to determine whether oxytocin-stimulated PGF_2α was significantly increased when ewes were fed a diet high in n-6 compared with a control diet low in n-6. Merino x Border Leicester ewes (n = 30) received one of two dietary treatments, either high in n-6 (70 % oat grain) or low in n-6 (control diet, 100 % cereal/legume silage). Ewes consumed the diets for 44 days prior to two consecutive oxytocin challenges. Plasma n-6 and PGF_2α metabolite (PGFM) concentrations following oxytocin challenge were greater (P < 0.05) when ewes were fed a diet high in n-6 compared with the control diet. A higher availability of n-6 may have lead to an increased in vivo synthesis of PGF_2α, however, further research is required to determine the exact mechanisms involved.     

应用绵羊肝细胞生长因子治疗小鼠急性中毒性肝损伤的疗效

将小白鼠随机分组，用四氯化碳（CCl4）造成急性肝损伤模型，以sHGF进行治疗。结果sHGF治疗组的小鼠血清GPT水平比肝损伤组明显降低（P＜0．001）；肝细胞变性、坏死等病理损伤也比肝损伤组明显减轻，可见大量的新生肝细胞；肝细胞超微结构提示，治疗组肝细胞核及胞浆内各种细胞器的损伤程度，比肝损伤组明显减轻，尤以线粒体和粗面内质网更为明显。     

The effect of feeding system in the expression of genes related with fat metabolism in semitendinous muscle in sheep

The effect of feeding system on the expression of LPL, ACACA, FASN, FABP4, DGAT1, SCD, CPT1B, PRKAA2, LEP, SREBP1, PPARG, PPARA and CEBPB genes in semitendinous muscle was studied. Forty-four single born male lambs of the Rasa Aragonesa breed, allocated to four different dietary treatments, were used: grazing alfalfa, grazing alfalfa with supplement for lambs, indoor lambs with grazing ewes and drylot. Significant differences were found in the expression of genes LPL, ACACA, FASN, FABP4, CPT1B and SCD. Genes related to adipogenesis (LPL, ACACA, FASN, FABP4, and SCD) are up-regulated in the intensive groups. In grazing groups CPT1B gene expression, related to β-oxidation process, is up-regulated. The relative expression of CPT1B was 1.54 fold higher in ALF+S, and 0.43 and 0.37 fold lower in IND- GRE and IND, respectively. The results support the hypothesis that changes in fatty acid profile due to feeding system implicate changes in the mRNA expression level of genes related with fat metabolism. Feeding strategy is an important tool to manipulate intramuscular fatty acid profile in meat through altering gene expression of enzymes related with fat metabolism.     

Display life of sheep meats retail packaged under atmospheres of various volumes and compositions

Longissmus dorsi loins were removed from Suffolk cross-breed lambs (4–9 months) and hoggets (15–20 months). The effect of package gas composition was investigated by packaging loins with gas mixtures containing 80:20:0, 60:20:20 and 60:40:0/O₂:CO₂:N₂ with a 2:1 headspace to meat volume ratio. The most effective gas mixture for prolonging shelf-life was used to study the effect of different headspace to meat volume ratios. Loins were packaged with a headspace to meat volume ratio of 2:1, 1.5:1 or 1:1. All modified atmosphere (MA) packs were held under refrigerated display conditions (4 °C, 616 lx) for 12 days. Loins were assessed for microbial, oxidative and colour stability and headspace composition every 3 days. The 80:20:0/O₂:CO₂:N₂ gas composition and the 2:1 headspace to meat volume ratio was the most effective packaging combination at maintaining and prolonging the attractive red colour of MA packaged lamb and hogget meat. 80:20:0/O₂:CO₂:N₂ resulted in significantly (p<0.01) higher Hunter a values in lamb. The 2:1 ratio gave higher visual assessment values in lamb and higher Hunter ‘a' values for hogget meat throughout the trial. The 2:1 ratio was the most effective at decreasing Pseudomonas and increasing the numbers of lactic acid bacteria in the total microbial load in both lamb and hogget meat. Lipid oxidation in lamb and hogget meat occurred at a slower comparative rate than discolouration or microbial growth and was not the major determinant of shelf-life. The 2:1 headspace to meat volume ratio was most effective at maintaining the initial gas mix in both lamb and hogget MA packs.