Geology and structure of 1,000 square miles of granulite-upper amphibolite facies gneisses cut by syn- and late-kinematic intrusions are described. The circular post-kinematic Mutton Bay alkaline syenite (631 m.y.) is divided into three main intrusive groups on the basis of chemistry, mineralogy, and field relations. Differentiation includes gravity settling and flow differentiation, while intrusion involved early stoping and assimilation with late faulting. Depth of the present level below the roof of the intrusion is estimated at 6-8 miles and temperature of crystallization of felspars in the early magmas at greater than 1015°C at less than 500 bars water pressure. Orthoclase inverted to microcline in foliated rocks that intruded as crystal mushes. A giant gabbro dyke with syenite differentiate (470 m.y.) is intruded by diabase and trachyte dykes. Carbonate enrichment in the trachytes is accompanied by high potash felspar content. Sandstone dykes are the only Paleozoic sediments.

Meat tenderness is regarded as the single most important characteristic of meat quality. Fifty Bonsmara feedlot steers were fed a commercial feedlot ration (10,5 MJ MElKg DM, 12% CP), supplemented with 0,15mg Zilmaxlkg live weight in the feed and with different levels of vitamin D3 (1 to 5 X 106 IU Vit D3 /day) for five days prior to slaughter. The steers were randomly allocated to the vitamin D3 treatments and a control group that received no vitamin D3 supplementation. The steers were fed from ca. 248 ± 3 kg live weight, while Zilmax was fed for the last 35 days to a target weight of ca 400kg. All steers were slaughtered at a commercial abattoir after a Zilmax withdrawal period of 7 days. Samples from m. longissimuss lumborum were collected 24h post-mortem for sheer force testing on an Instron apparatus equipped with a Wamer Bratzler shear blade. Cooking loss was determined by measuring the amount of fluid loss after cooking. Feedlot performance, carcass characteristics and drip loss of meat samples did not differ significantly between the different vitamin D3 treatments. The inclusion of 5 X 106 IU of vitamin. D3 resulted in significantly lower shear force (SF) values compared to the steers in the control group. The results suggest that dietary supplementation of 5 X 106 IU of vitamin. D3 may significantly improve the tenderness of meet from steers fed 0, IS mg Zilmax ®/kg live weight for the last 35 days in the feedlot. The aim of the second study was to explore the effectiveness of the use of electrical stimulation on tenderness of mutton. In this experiment 22 wethers of class AB weighing between 45 and 50kg were used. The carcasses were assigned to two treatment groups, of which group one was electrically stimulated (ES) and the other group was not electrically stimulated (NES). The results revealed that electrical stimulation did not significantly affect of the fatty acid content of meat and crude fat content. Treatment however, significantly (P< 0,038) influenced the moisture content of the samples. There was a variation in SF values between the two treatment groups; SF of samples from the ES group were lower compared to that of the NES group. This suggests that ES can be successfully applied to reduce the variation in tenderness within the class- AB mutton. / Dissertation (MSc(Agric) : Meat Science)--University of Pretoria, 2007. / Animal and Wildlife Sciences / unrestricted

No description available.

Mutton meat was tested in different products in order to obtain prototype products in which mutton can effectively be used without the objectionable mutton off flavor. Mutton flavor reduction was achieved in the processed meat products by: (a) lowering mutton fat to a level of 10% or less, (b) using spices, smoking and/or curing, (c) substituting fat from beef or pork for mutton fat, and (d) the action of microbial starter cultures. Four taste panel sessions were set up to rate these products against an all beef or all pork control for consumer acceptability. Taste panel results indicate that flavor had the greatest effect on overall acceptability of these products, compared to texture and appearance. Proximate meat analysis for fat, protein, moisture and ash were performed using the Technicon InfraAlyzer 400R and the results were compared with values obtained by reference AOAC methods. Correlation coefficients of 0.992, 0.867, 0.992 and 0.511 were obtained for fat, protein, moisture and ash respectively. The two methods were not significantly different (p = .05). These results indicate that the InfraAlyzer may be used as a rapid method for proximate analysis of fat, protein and moisture.

The effects of micrococci on sensory characteristics of different batches of summer sausages were determined. Sixty four salt-tolerant indigenous isolates were selected from beef or mutton treated with 1.5 or 3.0% sodium chloride and 120 ppm sodium nitrite, and held at 5 or 10 C for 5 days. These isolates (61/64) were identified as staphylococci and micrococci. Summer sausages were made from several lamb, ewe, and ram carcasses which were hand deboned and blended after grinding to contain 22% fat. Six summer sausage treatments were prepared using two different sources of commercial starter cultures including Micrococcus species or Micrococcus varians and Lactobacillus plantarum, an indigenous Micrococcus isolate, a microbial lipase, or encapsulated lactic acid. Three sensory panel sessions rated these products for consumer acceptability. Sensory panel results indicated that starter culture treatments did not improve sensory characteristics of the summer sausage over the treatment containing encapsulated lactic acid. Lipase addition caused a general reduction in sensory panel ratings for flavor, texture, appearance, and overall acceptability of the summer sausage (p = 0.05).

Thesis (MSc Food Sc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Please refer to fulltext for abstract. / AFRIKAANSE OPSOMMING: Sien asb volteks vir opsomming

The aim of this thesis was to determine the content of biogenic amines and polyamines, specifically putrescine (PUT), spermidine (SPD) and spermine (SPM) in mutton meat during storage and heat treatment. The meat of slaughter animals is rich in these amines but, unfortunately, data on the content of mutton meat whether in slaughter bodies as well as during storage or heat treatments in the literature are still missing. The samples were provided by small farmers and the animals were hybrids of several breeds. The samples were taken from the thigh and back. The samples of lamb meat were frozen and the ones were watched from 0-6 months. The samples of leg were cooled and packed into three different types of packaging. It was the type of packaging in a polyethylene bag (PE), vacuum packed (VP) and controlled atmosphere packaging (MAP). All the samples were analyzed in the days and also on the initial concentration at day 0. For frozen and cooled (chilled) samples which were stored in PE and VP was observed the decrease in all monitored amines. Only the packaging in MAP occurred in the SPD to a slight increase over the initial content. From heat treatments were performed usual preparations of the meals which are made in central Europe and the meals were cooked on particular days. The highest decrease was measured in roasted meat, then stewed and cooked meat in this order. Reported data are comparable to published data for pork and beef meat stored under the same or similar conditions. I think that these data can help to extend the data in the literature.

Records of the La Rochelle S.A. Mutton Merino stud were analysed to determine the importance of possible contributing non-genetic sources of variation on growth and reproductive traits. Growth traits analysed were pre-weaning weight (42dW), weaning weight (100dW), 205d weight, ADG's and Kleiber Ratio's (KR) for both 42d and 100d. All the included effects, i.e. year, sex, birth status, season, age of dam and the year x sire interaction, were highly significant (P<0.001) for the growth traits. Reproduction traits measured were mean number of lambs born per ewe per year, mean Kg lamb weaned per ewe per year, percentage twins and fecundity. Year was the only significant effect (P<0.001) for all four reproduction traits. Data of records between 1974 and 1995 were used to estimate additive direct and additive maternal heritabilities for seven growth traits. The estimates of the direct heritabilities varied between 0.166 for 42dW and 0.513 for 205dW. The estimates of the maternal heritabilities were within the 0.042 (42dW) to 0.370 (100dADG) range. Estimates of the covariance between the direct additive and maternal additive components were generally negative and of a substantial size (-0.215 to -0.674). Additive direct and additive maternal heritabilities for four reproductive traits were also estimated. The estimates for direct additive heritabilities varied between 0.039 for fecundity and 0.177 for Kg lamb weaned per ewe per year. Estimates for the maternal additive heritabilities were correspondingly low, varying from 0.007 for lambs born per ewe per year to 0.197 for percentage twins. Estimates of covariance between the additive direct and additive maternal components were negative. Genetic trends of the flock were studied. The main objective of the breeder was to improve the reproductive efficiency of the flock, whilst decreasing the incidence of very large lambs. Selection pressure on reproductive performance hasn't yet attained the desired effect as three of the four reproductive traits measured, showed very little or no improvement. Lambs do however have lower body weights, while the 100dADG and 100dKR have improved. / Dissertation (MSc(Agric))--University of Pretoria, 2004. / Animal and Wildlife Sciences / unrestricted

The objective of the study was to determine perceptions of rural consumers on mutton quality, and the quality of mutton at purchase points in the Eastern Cape Province, South Africa. The study was conducted in five different municipalities (Buffalo City, Nkonkobe, Ngqushwa, Lukhanje and Amahlathi). A survey was conducted where a sample of 215 consumers were randomly selected and interviewed, either at point of purchase or as they left the shops. The survey was not limited to the shoppers only but also extended to households from the villages. Questions on some of the most important meat quality cues were compiled. The physico-chemical quality of mutton purchased from different shops was also determined. Forty different shops and butcheries selling mutton from all the selected municipalities were visited. Different parts of mutton samples were bought. Physico-chemical qualities of mutton such as colour (L* - lightness, b* - redness and a* - yellowness) and meat pH measurements were taken at points of purchase. Cooking loss and tenderness evaluations were later done at the Meat Science laboratory at the University of Fort Hare. The results indicated that price was one of the major factors affecting the purchasing decisions of consumers. Thirty four percent of the consumers preferred mutton as compared to other protein sources, even though they were not buying this type of meat because it was not affordable to them. Both male and female consumers suggested that more sheep farmers need to be established in order to reduce the levels of imported mutton into South Africa. They also highlighted that selection programmes that will result in efficient sheep production and reduced mutton prices need to be implemented. Meat at points of purchase was affected by season resulting in lower lightness (L*24.7±0.49) values in winter and higher (L* 32.2±0.49) in Spring. The class of shop did not have an effect on meat quality attributes. Trotter had high values of lightness (L*30.4±2.78a), redness (a*30.4±2.78a), yellowness (13.1±1.08a), pH (6.3±0.12a), tenderness (24.9±3.69b) and cooking loss (39.5±4.38ab). The number of days from when the meat was put on the shelves to the time when it was purchased for consumption (days to purchase) had a significant (P<0.05) negative correlation with the Warner Braztler Shear Force (WBSF)values and lightness of the meat. Significant negative (P < 0.05) correlations between pH and colour of the meat (L*, a* and b*) were also observed. It was concluded that rural consumers perceive the quality of mutton as the best and that the physico-chemical quality of meat purchased from different shops was different, largely based on the part of meat, meat storage conditions and not necessarily on the class of the shop.

Effects of pre-slaughter sheep handling and animal-related factors on Creatine Kinase levels and physico-chemical attributes of mutton By Chulayo Amanda Yucca The objective of the study was to determine the effects of pre-slaughter sheep handling and animal-related factors on Creatine kinase (CK) levels and physico-chemical characteristics of mutton from South African sheep breeds. One hundred and seventy-three castrated male sheep from four breeds (15 Dormer, 46 South African Mutton Merino, 77 Dorper and 35 Blackhead Persian) were used. The animals were grouped according to age categories. The grouping was as follows: Group 1 (6 ≤ 8 months), Group 2 (9 ≤ 12 months) and Group 3 (13 ≤ 16 months). Blood samples for CK determination were collected at exanguination using disposable vacutainer tubes. Representative samples of the Muscularis longissimuss thoracis et. lumborum (LTL) muscle were taken for the determination of ultimate pH (pHu), colour (L*-lightness, b*- redness and a*- yellowness), thawing and cooking losses and meat tenderness. Significant (P<0.01) breed effects were observed on CK levels with Dormer having the highest CK values. Significant linear relationships were observed between pre-slaughter condition and CK levels. There were positive correlations between colour coordinates L* and b* (r =+0.22) and between a* and b* (r =+0.63). Cooking loss and Warner Braztler Shear Force (WBSF) values were positively correlated (r =+0.29). The Principal Component Analysis (PCA) showed a significant variance for CK and between physico-chemical characteristics of mutton. There were no relationships between CK levels and physico-chemical characteristics of mutton. Significant breed and age effects on pHu, L, a*, b*, thaw %, CL and WBSF of mutton were observed. iv It was concluded that, pre-slaughter conditions affect CK levels and physico-chemical characteristics of mutton. However, there were no relationships between CK levels and physico-chemical characteristics of mutton.