Effects of breed and castration on slaughter weight and carcass composition of goats

Goat Meat: Production and Quality Attributes

Goat meat could be a sustainable source of red meat. Its farming requires minimal input, is suitable for free-range farming, and produces a healthier red meat option as it is lean. Although goat meat has advantages for meat production, it still needs to be established as a valuable part of the meat trade market. But, currently, goat meat production is less specialized; there is less intense breed selection for premium meat production, and often the animals are farmed with a multifunctional purpose, such as for their meat, fiber, and milk. The less structured goat meat industry contributes to the inconsistent quality of goat meat. This paper attempts to describe the characteristics of popular goat breeds and indigenous goats as a source of meat and the potential of various goat breeds for meat production. Additionally, this paper presents goat meat's quality and physicochemical and sensory attributes that are relevant to understanding the unique attributes of goat meat. Much work is needed for the goat meat processing industry to develop its potential.

Early weight development of goats experimentally infected with Mycobacterium avium subsp. paratuberculosis

Johne's disease is an infectious chronic inflammatory bowel disease in ruminants. The key factor for the management of this disease is an early positive diagnosis. Unfortunately, most diagnostics detect animals with Johne's disease in the clinical stage with positive serology and/or positive fecal cultures. However, for effective management of the disease within herds, it is important to detect infected animals as early as possible. This might only be possible with the help of parameters not specific for Johne's disease but that give an early indication for chronic infections such as weight development. Here we report our findings on the development of total body weight and weight gain during the first six months of goats experimentally infected to induce Johne's disease. Twenty dairy goat kids age 2 to 5 days were included in this study. Goats were divided into two groups: a negative control group and a positive infected group. The weight was obtained weekly throughout the study. Goats of the positive group were infected at the age of seven weeks. We detected significant changes in weight gain and total body weight as early as one week after infection. Differences are significant throughout the six month time period. Weight as a non-specific parameter should be used to monitor infection especially in studies on Johne's disease using the goat model. Our study suggests that goats with Johne's disease have a reduced weight gain and reduced weight when compared with healthy goats of the same age.

Carcass yield traits of kids from a complete diallel of Boer, Kiko, and Spanish meat goat breeds semi-intensively managed on humid subtropical pasture

Bucklings (n = 275) from a complete diallel of Boer, Kiko, and Spanish meat goats were slaughtered at 7 mo of age (4 mo postweaning) to evaluate genetic effects on carcass yield. Breed of sire did not affect (P > 0.05) live, carcass, and primal weights. Conversely, breed of dam was a consistently significant source of variation for carcass weight traits. Kiko dams produced kids with heavier (P < 0.05) live, carcass, and primal weights than Boer dams. Weights from Spanish dams were intermediate to Boer and Kiko with the significance of differences varying by trait. Cold carcass dressing percent was affected (P < 0.01) by breeds of sire and dam. Boer sires decreased (P < 0.05) dressing percent compared with Kiko and Spanish sires. Dressing percent was also less (P < 0.01) from Boer dams than from Kiko dams; Spanish dams were intermediate and did not differ (P > 0.05) from Boer or Kiko. Subjective conformation scores for muscularity were affected (P < 0.01) by breeds of sire and dam. Boer-sired kids had better (P < 0.01) live scores than Kiko-sired kids. Progeny of Boer dams had better (P < 0.05) live scores than progeny of Spanish dams. Boer-sired kids also had better carcass scores (P < 0.05) than Kiko-sired and Spanish-sired kids. Breed differences for primal cut proportions were negligible. Proportional boneless meat yields did not vary (P > 0.05) by breeds of sire or dam. Direct effects of Boer were negative for carcass weight, dressing percent, and shoulder weight and positive for proportional leg weight. Direct effects of Kiko were positive for carcass weight and shoulder weight and negative for proportional leg weight. Direct effects of Spanish did not differ (P > 0.10) from 0 for any trait tested. Heterosis levels were similar among breed pairings. Heterosis was substantial (P ≤ 0.05) for live, carcass, and primal weights (5 to 9%) but not for dressing percent, proportional boneless meat yield, or primal weight proportions (<2%). Significant genetic variation was observed among goat breeds for carcass yield traits. Dam breed was more influential than sire breed. Boer germplasm was not superior to Kiko or Spanish germplasm for carcass yield when semi-intensively managed on humid, subtropical pasture. Results emphasize the importance of comparative breed evaluations to provide industry with reliable information on carcass yield among goat genotypes.

Performance and carcass characteristics of intact and castrated male Black goat kids fed diets of various energy levels

Thirty Black goat male kids were used in a 3 × 2 factorial arrangement to evaluate the effects of three dietary energy levels (EL) and early castration (TRT) on growth performance, body and carcass characteristics. Upon weaning at 90 days of age, kids were randomly divided into three equal groups (n = 10: five intact and five castrated) and assigned to one of the three dietary treatments containing 15% CP and different energy levels: low (LEL; 10.44 MJ ME/kg DM), medium (MEL; 11.60 MJ ME/kg DM) and high energy (HEL; 12.90 MJ ME/kg DM). Kids were individually fed on an ad libitum basis and were slaughtered at the end of the fattening period. Results showed no differences between castrated and intact kids in feed and nutrient intake. The level of dietary energy affected dry matter intake (P < 0.05), metabolisable energy intake (P < 0.01), crude protein intake (P < 0.05), neutral detergent fibre (P < 0.001) and acid detergent fibre intakes (P < 0.001). Dry matter intake was 280, 305 and 264 g/kg W0.75.day for kids receiving LEL, MEL and HEL diets, respectively. Metabolisable energy intake was the highest for kids receiving the MEL diet (0.90 Mcal/kg W0.75.day) compared with LEL (0.73 Mcal/ kg W0.75.day) and HEL (0.88 Mcal/kg W0.75.day) diets. Final liveweight and average daily gain (ADG) were greater (P < 0.01) in MEL diets. Kids fed MEL gained 133 g/day, while ADG values were 92 and 100 g/day for kids fed LEL and HEL diets, respectively. Total muscle percentage was greater (P < 0.05) for kids fed MEL diets (55.9%) compared with LEL (53.8%) and HEL (51.1%) diets. Castrated kids had lower (P < 0.01) carcass muscle percentage, but higher carcass (P < 0.01) and subcutaneous (P < 0.001) fat percentages than intact kids. It can be concluded that the best growth performance was observed in kids receiving the MEL with no differences between castrated and intact kids. Castration influenced accretion of fat in castrated kids.