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The role of objective and subjective evaluation in the production and marketing of goats for meat
chapterposted on 2012-01-01, 00:00 authored by Bruce McGregor
Objective and subjective evaluations of goats for meat production are related to important determinants of production and profitability. The most important attributes in assessment of goats for market are: live weight; body condition score; and the age of goats. As goats grow, their carcass and body organs increase in weight in proportion to the empty body weight. For farmers and field workers the linear regression approach for estimating carcass weight by measuring live weight is the most suitable as it accounts for 88 to 97% of the variation in carcass, offal and boneless meat weight. Live weight scales or heart girth tapes should be used and the risks and errors associated with these methods are summarized. The proportion of a live goat that is the carcass, known as dressing percentage, increases from 35% to about 50% as goats grow. The usefulness and errors associated with dressing percentage in field estimation are discussed. A valuable subjective method for estimating the nutritional status of goats is the use of body condition scoring as it accounts for 60 to 67% of the variation in live weight change, carcass weight and fat reserves of goats. A method for body condition scoring and a similar fat scoring system are explained. Body condition score is also associated with mortality risk and reproductive performance of goats. The number of permanent incisors in the lower jaw of goats is a method of estimating the age of goats but is biased by differences in live weights of goats. The value and role of ultrasound scanning the carcasses of goats is summarized. For the marketing of kid meat no permanent incisors should have erupted. Other useful practices for the successful marketing of goat meat are discussed including: knowing market specifications and chemical withholding periods; animal health; prevention of bruising; identification of goats; size of consignments; timeliness; provision of paperwork. A checklist is provided. The use of subjective and objective assessment techniques in evaluating goats for meat production will provide the best results. Where only subjective assessment techniques are available they will provide satisfactory performance provided the skills have been learnt and are applied.