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 The Tennessee Goat - A Genetic Resource for Meat Production
D. P. Sponenberg The Tennessee Goat is frequently overlooked as an important genetic resources for goat meat production. Tennessee goat’s have a number of characteristics that combine to provide it a useful role in commercial meat goat producing systems. On top of that they are personable, pleasant, and beautiful. The most striking characteristic of the Tennessee goat is the condition of myotonia congenita . This condition is strictly muscular, and causes the muscles to become rigid when the goat is startled, moves suddenly, or steps over a low barrier. The condition is due to changes in the muscle cell membranes, and has nothing to do with the nervous system. The characteristic stiffening has given rise to a number of names for this breed: Fainting, Nervous, Stiff-Leg, Wooden-Leg, Scare, and Myotonic. The myotonia congenita goes hand in glove with heavy muscling. By whatever name, these are unique goats with an array of useful characteristics. I am by no means unbiased on the topic of these goats, since they are my own breed of choice, and I am owned by well over a hundred of them. BREED HISTORY The unique Tennessee breed first enters historical note in the 1880s, when an itenerant farm laborer arrived in middle Tennessee with four of these goats and a zebu cow in tow. The laborer, Tinsley, worked in the area for few years, and then moved on. Upon his departure one of his employers, Dr. Mayberry, purchased the goats and their offspring. This is the beginning of the breed, although the ultimate origin of them is likely to always remain a mystery. They are unique among goats worldwide, as far as anyone knows. Most breeds do not simply descend from the heavens intact, so these must go back to something even though we do not know what. The ears are medium sized, and usually held horizontally. A few are somewhat lopped, but are medium rather than large, and lack the characteristic width and carriage of Nubian and Boer crosses, and also lack the character of Spanish goats. They also lack the short, very erect character of Pygmies and many Swiss breeds. Many of the ears have a distinct wave or ripple about halfway down the length of the ear. Colors are extremely variable, although some breeders select for a limited range of colors. Black and white goats are relatively common as a result of having been favored by some of the original Tennessee breeders, although even among the older breeders the color preference varied. Many, many color combinations do occur in these goats. Hair coat varies from very short and smooth, to very long and shaggy. The entire range of hair types occur in most strains, including old foundation strains. While some prefer the smoother goats, the shaggy ones are very resistant to inclement weather. The above characteristics could be passed off as somewhat “cosmetic” aspects of the breed. The consistency of these traits is an important reflection of breed type and breed purity. This breed is much more than stiffness, even though stiffness is one of its most unique characteristics. The head and body conformation traits all go together to define the “type” of this breed, and this is an important reflection of purity and utility. It is somewhat strange that the head and hair coat of breeds provides the most indication of type, while being of limited commercial utility. Still, these traits are very important to a breed as a purebred gene pool. They help define the breed and set it off from other pure breeds. Other traits that are consistent in this breed include thick muscling, and thick conformation throughout. The significance of this for meat production is that these goats simply have more muscle for their weight than do other goats. All results are preliminary, but suggestions from the work of Terry Gipson and Stephan Wildeus at Virginia State University are that the meat to bone ratio in Tennessee goats is about 4:1, compared to Pygmies, Spanish, and Brush goats at 3:1. This is an ongoing study, and should include the Boer and maybe Kiko before establishing these ratios as significant. These early results do indicate that the breed should not be discounted as a meat producing animal. Anecdotal evidence is that the meat is tender and tasty. While all goats meet that criterion, folks who have tried Tennessee goats as well as other tend to rank the Tennessee at the top of meat quality. The meat is consistently praised for tenderness, which at first thought might seem at variance with the stiffness encountered while the goat is alive. It is important to realize that the stiffness in no way results in tough meat, but rather just the opposite! In keeping with their size, the growth rates on Tennessees are moderate. Few data exist on weights and rates of growth. In my own herd, birth weights have tended to cluster between four and six pounds, with very few below this, and a few as high as eight pounds. Mature weights are variable, from 60 pounds in the smaller animals of the breed, up to much larger. My biggest, oldest (as in ancient) doe tips the scales at about 105 pounds, while some strains have does up to 130 pounds. Males are correspondingly bigger, but don’t get weighed as frequently as the does due to my management constraints. Some males are reputed to be 265 pounds or larger, and while this might be accurate I have not seen one of these on the scales. My estimate is that 175 pounds for a grown male is a reasonable example of the larger end of the breed. Reproductive function in the Tennessee goats is somewhat variable, which means that the selection background of specific goats is an important factor. Some appear to be seasonal. Others appear to be very nonseasonal, and I have had some does kid at six month intervals. Accelerated kidding is potentially possible with this breed, but the does and bucks need to be specifically selected for this trait. In my own herd many of the does seem to cycle throughout the year, but some bucks are poorly interested in mating out of season. This is circumvented by using multi-sire teams for out of season matings - the competition seems to inspire the boys somewhat. As selection proceeds, though, they do become consistently nonseasonal. Fecundity and milk production in the does are good. Most breeders report that twins are usual, and that triplets and quadruplets are not uncommon. Does have no problem rearing triplets unassisted. Those with four and five kids have a challenge which few does can meet, and some of those kids need to be supplemented. My results indicate a kidding rate of 200% for does over one year old. This is made up by a few triplets compensating for the ones that have singles. Most of mine that kid at a year only have a single, although in some herds twins are routine in these as well as the older does. Breeders of meat goats seem somewhat divided on when to mate for the first kidding, and whether singles or multiples are better for the first kidding. Mine tend to kid right at twelve to fourteen months old, and I prefer that they have singles. The Tennessee goats are good foragers. They are active in seeking out their own food, and are efficient with winter feed (grass hay and cracked corn in my situation). They enjoy browsing, but are less agile climbers than nonmyotonic goats. This eases stresses on fencing, and limits the height and aggressiveness of their browsing as well. This can be an advantage for maintaining forages for their use. Most breeders use forage based system, so few of these goats are pushed with high concentrate diets or creep feeding. When evaluating growth rates it is important to put this on the background of the type of nutrition the animals are provided. Early work also suggests that the Tennessee goat is somewhat parasite resistant. Parasite resistance is always going to be relative to management styles and environmental constraints. When compared to other common breeds, the Tennessee goats appear to hold their own in keeping parasites at bay. This is an important trait for continued selection, and is present at a high enough level in the breed to warrant such a program. My own herd shows much more resistance to parasites than do the sheep on the same farm. The Tennessee goat has much to offer meat goat producers interested in a well-adapted goat for a low-input forage based system. Their heavy muscling and environmental resistance are especially attractive as components of production systems. They are a nearly ideal converter of rough forage into high quality meat.
Dr. Phillip Sponenberg, DVM, PHD |
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Holstein