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THE BOER GOAT By: D. M. Barry and R. A. Godke Adaptability and HardinessThe Boer goat is one of the most hardy of all small stock breeds in the world. Although acclimatization is often a slow process, taking a year or longer, the Boer goat has the ability to adapt to almost any climate, from the hottest dry desert climate as in Namibia and Australia, to the snow covered mountains of Germany (1). TABLE 1. Production Parameters for the Boer Goats In Namibia & Germany PARAMETER NAMIBIA GERMANY Kidding 98.0 % 100.0 % Kids per annum 1.9 1.9 Birth weight - 4.0 kg Weaning 97.4 % 100.0 % 100 day mass 23.5 kg 24.0 kg ADG OVER 100 DAYS Singles 239.5 gm 257.0 gm Twins 236.7 gm 193.0 gm Triplets 217.7 gm 182.0 gm Male Kids - 213.0 gm Female Kids - 184.0 gm The Boer goat has strong, sturdy legs and can travel long distances. It moves just as easy in dense shrubbery as it does over rugged mountainous areas. They have been known to travel over long distances for food and water. They are believed to be able to survive droughts without supplementary feed, the best of all the goat breeds. The Boer goat is very resistant to diseases, like bluetongue, and to a lesser degree to enterotoxemia (Clostridium perfringens type-D), and to poisonings like prussic acid (HCN). Grazing habits make the Boer goat less susceptible than other goat breeds to contamination by internal parasites. The boer goat is a browser, and if shrubs are not available, it prefers not to graze in the early mornings when the dew on the grass makes it most favorable for animal contamination (l,5). The hardiness and adaptability of the Boer goat gives it a reproductive life of up to 10 years or longer. Sexual Cycle and FecundityThe number of kids born per Boer goat per breeding season ranges between 1.6 and 2.1. The weight of Boer goat females at puberty is given in Table 2. TABLE 2. Age & Body Weight of Boer Goat Females at Puberty (6) BIRTH OF OFFSPRING 1st ESTRUS MASS AT 1st ESTRUS During Kidding Season 157.2 days 27.4 kg Out of Kidding Season 191.1 days 31.1 kg Although the Boer goat is a partially seasonal breeder, complete anestrus does not occur in the breed (7). Shortening daylight length generally stimulates the does, with a peak in sexual activity during the months of April and May in the southern hemisphere. The period of least sexual activity is usually from October to January. Tables 3 and 4 gives the estrous cycle and gestation period of the Boer goat doe (3,8), respectively. TABLE 3. Estrous Cycle Length of estrous cycles 20.7 days Does with cycles LT or EQ to 13 days 16.6 % Does with cycles GT or EQ to 25 days 10.2 % Mean length of estrus 37.4 hours Does ovulating between 32 & 38 hours 87.0 % post-onset of estrus TABLE 4. Gestation Period MEAN GESTATION LENGTH 148.2 days Does with singles 149.1 days Does with twins 147.8 days Does with triplets 146.8 days POSTPARTUM ANESTROUS PERIOD Kidding in kidding season 37.3 days (Sept - Oct) Kidding outside of season 59.9 days (March - April) First cyclic activity post-kidding 20.0 days Kidding to pregnancy 62.0 days (no breeding season) During the beginning of the breeding season (February - March in the southern hemisphere), the estrous cycles tend to be shorter, while during the period of least sexual activity the cycles are often longer than 21 days. Milk ProductionIn the Boer goat, as with other goats, the average daily gain (ADG) of the kids is directly related to the milk production of the dam. With a preweaning ADG of 300 gm, the doe must produce up to 2.5 liters of milk per day. The doe must reach her peak production during the 4th week of lactation. Although the doe produces enough milk to raise two kids, the supplementation of feed to the doe with twins or triplets is highly advisable. Feed supplementation will clearly reflect in the weaning weight of the kids (9). GrowthA comparison in growth rates obtained during 1986 and 1989 from phase D2 of the National Mutton Sheep and Goats Performance Testing Scheme (10) is presented in Table 5. TABLE 5. Average Daily Gain (ADG) & Food Conversion Efficiency (FCE) of Young Boer Goats GROWTH 1986 1989 ADG of fastest growers 118.0 gm 163.0 gm ADG of slowest growers 13.0 gm 22.0 gm DRY FIELD GRAZING/1 kg GAIN IN MASS (FCE) FCE of fastest growers 17.7 kg 13.6 kg FCE of slowest growers 154.7 kg 88.0 kg The Boer Goat Breeders Association (of South Africa) joined the National Mutton Sheep and Goats Performance Testing Scheme in 1970. The increase in average 100 day adapted weaning weights for the 12 year period after 1970 is given in Table 6. TABLE 6. Average 100 Day Adapted Weaning Weights of Performance Tested Boer Goat Kids YEAR BUCK KIDS DOE KIDS 1970 24.0 kg 21.9 kg 1971 25.4 kg 23.0 kg 1972 26.3 kg 24.1 kg 1973 22.1 kg 21.1 kg 1975 23.6 kg 21.7 kg 1977 22.4 kg 21.3 kg 1978 27.1 kg 24.9 kg 1979 36.6 kg 29.2 kg 1980 29.0 kg 25.3 kg 1982 32.3 kg 27.8 kg As illustrated in Tables 5 and 6, when purposeful selection for growth rate, weaning weight and post weaning weight gain is pursued in Boer goats, as much as 20% or more increase in ADG can be expected, with a subsequent decline in FCE. Meat and SkinThe Boer goat is raised for meat production, and has as such played an economical part in the meat trade in South Africa. If the Boer goat is slaughtered at an early age it has a tender and a very tasty meat. Boer goats must be marketed at a very young age with the carcass not weighing more than 23 kg on the rail. The dressed weight percentage at specific ages is given in Table 7. TABLE 7. Dressed Weight Percentage of Slaughtered Boer Goats at Different Ages AGE DRESSED PERCENTAGE 8 to 10 Months 48 % 2 Teeth 50 % 4 Teeth 52 % 6 Teeth 54 % Full Teeth Placement 56-60 % No other mutton breed has a higher dressed weight for young animals. A live-mass weight of 38 to 43 kg is considered the best marketable weight for young goats. The carcasses of kids weighing less than 18 kg lacks sufficient fat covering and is often discriminated against. "Kids" implies the meat of a goat with no permanent incisors. Only kid carcasses can be graded as "super", the best possible grade that can be achieved for goats. This classification has high quality carcasses with a thin layer of fat. Too little or too much fat or a weak conformation causes a lower grading of the carcass. Cross BreedingThe aim of cross breeding is to transmit the superior phenotypic characteristics of a breed or breeds to the F1 offspring. The Boer goat breed poses many of these outstanding phenotypic characteristics which can be clearly seen in its cross breed offspring. TABLE 8. Birth Weight and Weights at Different Ages of Boer Goat Crosses and Small East African Goats (SEAG) (11) AGES BOER GOAT CROSSES SEAG Birth 2.6 kg 2.3 kg 42 days 8.3 kg 6.9 kg 150 days 19.7 kg 14.9 kg 180 days 21.8 kg 16.2 kg 275 days 28.2 kg 20.2 kg 365 days 34.3 kg 22.0 kg Haas (1978) also compared the average daily gain (ADG) of the Boer goat crosses to that of the indigenous Small East African goats in Kenya (11). He found that the ADG was significantly better in the Boer goat crosses than in the indigenous Small East African goats. TABLE 9. Average Daily Gain (ADG) of Boer Goat Crosses and Indigenous Small East African Goats (SEAG) (11) STAGE BOER GOAT CROSSES SEAG Birth to Weaning 114.0(a) gm 84.0(b) gm Weaning to 365 Days 65.0(a) gm 32.0(b) gm (ab)The different superscripts in a row are significantly different ConclusionThe outstanding characteristics of the Boer goat as a meat goat, make the breed a primary choice when selecting a breed for hardiness, adaptability, fertility and growth potential. The Boer goat has the ability to transmit its superior phenotypic characteristics to other breeds when used for cross breeding. It is also an excellent animal to counter-attack bush encroachment, and when used in a free ranching cattle production system, it was found that the two species utilize the vegetation at different levels, and the income generated by the Boer goats can thus be taken as a bonus. References1. The economic value and characteristics of the Boer goat. Boer Goat News 9:51-53. Reprinted With Permission of The Authors
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