வெள்ளாட்டு இனங்கள் – வெளிநாட்டினங்கள்

ஆல்பின் (Alpines) இவை பிரான்சு, சுவிட்சர்லாந்து, ஆல்ப் மலைப் பகுதிகளைச் சார்ந்தவை. பல்வேறு நிறம் கொண்டவை. கறுப்பு, செந்நிறம், வெள்ளை மற்றும் இந்நிறங்களின் கலவையான நிறங்களுடன் காணப்படும். கடா 65 முதல் 80 கிலோ எடை கொண்டது. பெட்டை ஆடு 50 முதல் 60 கிலோ எடை கொண்டது.

ஆங்கிலோ நுபியன் (Anglo – Nubian)
 ஆடுகளின் ஜெர்சி என இவற்றைக் குறிப்பிடலாம். ஏனெனில் இவற்றின் பால் 4 முதல் 5% கொழுப்புச் சத்துக் கொண்டது. இவ்வினம் இங்கிலாந்து நாட்டில் எகிப்து நாட்டு நுபியன் இனக் கடா மற்றும் இந்திய சமுனாபாரி பெட்டை ஆடுகளின் இனச் சேர்க்கையால் தோற்றுவிக்கப்பட்டது. இவை கறுப்பு, சிவப்பு, வெள்ளை மற்றும் இவை கலந்த நிறங்களுடன் காணப்படும். சமுனாபாரி போன்று ரோமானிய மூக்கும், நீண்ட தொங்கும் காதுகளும் கொண்டவை. ஆண், பெண் ஆடுகளுக்குக் கொம்புகள் உள்ளன. கிடாக்கள் 65 முதல் 80 கிலோ எடை கொண்டவை. பெட்டை ஆடுகள் 50 முதல் 60 கிலோ எடை கொண்டவை.

சாணன் (Saanan) இது சுவிஸ் நாட்டின் இனமாகும். இது வெள்ளை நிறமுடையது. ஆல்பின் இனத்தையொத்த உடல் எடையுள்ளது. இவ்வினத்தின் சில வகை ஆடுகளுக்குக் கொம்பு இருக்காது. சில வகைகளுக்குக் கொம்பு இருக்கும். கொம்பு இல்லாமை டாமினட் ஜீன் காரணமாக ஏற்படுவது ஆகும். ஆண், பெண் இரண்டிற்கும் தாடி இருக்கும். பால் அளவு 2 முதல் 5 கிலோ வரை, கொழுப்புச் சத்து 3 முதல் 4% வரை.

தோகன்பர்க் (Toggenburg) இது சுவிஸ் நாட்டில் தோன்றியதாயினும் அமெரிக்க நாட்டில் சிறப்புடன் வளர்க்கப்படுகின்றது. இது இளம் பழுப்பு நிறமுடையது. வயிறு, கால் பகுதிகள் வெள்ளை நிறத்துடன் இருக்கும். எடை மற்ற வெளிநாட்டு இனங்களைப் போன்றது. பால் அளவு தினம் 5 முதல் 6 கிலோ.

அங்கோரா (Angora) இது ஒரு கம்பளி இன வெள்ளாடு ஆகும். இவை மொகேர் (Mohair) வழங்குகின்றன. ஓர் ஆடு, ஆண்டில் 4, 6 பவுண்டு மொகேர் வழங்குகின்றன. இதன் மூலம் சிறந்த கம்பளிகளும் ஆடைகளும் தயாரிக்கப்படுகின்றன. அங்கோரா ஆடுகள் அதிக அளவில் அமெரிக்காவிலும், துருக்கியிலும் வளர்க்கப்படுகின்றன.

சீன நீல ஆடுகள் (Blue China Goat) சீனாவில் சான்தாங் மாநிலத்திலுள்ள நீல ஆடுகள் 6 அல்லது 7 குட்டிகள் ஒரே வேளையில் ஈனும் குணம் கொண்டவை.

தொகுப்பு  : A R தியாகரஜன், கால்நடை மருத்துவர், சுவாமிநாதன் ஆராய்ச்சி நிறுவனம்,  புதுச்சேரி.

MEAT GOAT BREEDS

Goats of any breed or crossbreed are eventually slaughtered for human consumption. With the exception of the South African Boer goat imported via New Zealand in early 1993, there are no true meat goats breeds in the U.S. However, there are few breeds that stand out as more specialized for meat production. These are the Spanish, Myotonic, Nubian and Pygmy goats.

A clear indication that the meat goat industry is expanding is shown by the 13% increase in the number of goats sold through NC auction markets, from 27,874 in 1995 to 31,503 in 1996. Few crossbred animals having Boer genetics have yet been sold for meat. However, this is going to change in the near future because many producers have purchased purebred or ½ blood Boer bucks in 1996 due to the dramatic decrease in price of those animals. Boer genetics are finally becoming affordable and higher quality carcasses will soon be seen on the market.

Boer

The Boer goat of South Africa owes its name to the Dutch word "boer" meaning farm . The origin of Boer goats its vague and probably rooted in indigenous goats kept by Hottentot and migrating Bantu tribes, with a possible infusion of Indian and European bloodlines. The present-day improved Boer goat emerged in the 20th century, when South African farmers started breeding for a meat type goat with good conformation, high growth rate and fertility, short white hair and red markings on the head and neck. The South African Boer Goat Breeder's Association was founded in 1959 to establish breed standards for the emerging breed. Since 1970 the Boer goat has been incorporated into the South African National Mutton Sheep and Goat Performance and Progeny Testing Program, which makes the Boer goat the only known goat breed routinely involved in performance and progeny tests for meat production. There are approximately 5,000,000 Boer goats in Africa, of which 1,600,000 are of the improved type.

New Zealand and Australian companies have imported the Boer goat into their respective countries for improving their own meat goat industries. In April of 1993, the quarantine restrictions for the New Zealand Boer goats expired and animals became available for importation into the U.S. The Australian Boer goats will be released in October 1995. In June 1993, the North American Boer Goat Association was founded, breed standards were established and registry of animals was begun. According to New Zealand researchers, the plane of nutrition plays a greater role than the light/dark cycle for Boer goats to breed out of season.

	Male		Female
Live weight (lbs)	Avg	Max	Avg	Max
Yearlings	100	180	80	135
Adults	250	290	140	200

Spanish

The Spanish goat came originally from Spain via Mexico to the USA. It is now a meat type goat found primarily on or around the Edwards Plateau of Central Texas. The Spanish goat has the ability to breed out of season and is an excellent range animal because of its small udder and teats. In addition, Spanish goats are usually characterized as being very hardy, able to survive and thrive under adverse agroclimatic conditions with only limited management inputs. Within the general group of "Spanish goats" there are those that are purely Spanish, whereas others represent an amalgam of all genotypes introduced to the area. There have been obvious infusions of dairy and Angora blood in many Spanish herds but no organized attempt has ever been made to use them for milk or mohair production. The term "wood" (Florida), "brush" or "briar" (North Carolina, South Carolina), "hill" (Virginia), and "scrub" (Midwest Pennsylvania) goat tends to be used in the Southeast and elsewhere. Until recently, these goats were kept mainly for clearing brush and other undesirable plant species from pasture lands. In recent years, the escalating demand for goat meat and the expanding interest in cashmere production have focused attention on the Spanish goat. Current estimates of the Spanish goat population is around 500,000 heads. Several Spanish goat producers in Texas have been intensively selecting for increased meat production for the past several years. From information obtained from these producers, these "selected" Spanish goats appear to greatly outperform the ordinary Spanish goat used primarily for pasture maintenance.

Myotonic

The Myotonic goat has several aliases including "Tennessee Stiff-Leg", "Tennessee Wooden-leg", "Nervous Goat", "Fall-Down Goat" and "Fainting Goat". The Myotonic goat is a very meaty and muscular animal. This goat breeds out of season, and in many herds it is usual for does to kid twice a year. Number of kids vary from single to four. The Myotonic goat suffers from a recessive trait called myotonia. When frightened, it experiences extreme muscle stiffness causing extension of hind limbs and neck. In this startled state, if unbalanced, the animal will topple over like a statue or will stand immobile until the attack, usually lasting only 10-20 seconds, passes. According to a Texas neurologist, this type of involuntary isometric muscle contraction could build a more tender muscle than a muscle developed by strenuous use. Little known about the earliest history of this breed except that in the early 1880's a man appeared in Marshall County, Tennessee with a cow, three does and a buck of a unique strain. These four goats suffered from myotonic spells and were purchased by a Dr. Mayberry who propagated the breed. The population of Myotonic goats is informally estimated to be around 3,000 to 5,000 heads, with herds found primarily in Tennessee and Texas.

Nubian

The Nubian goat, also called Anglo-Nubian, is considered a dual- purpose goat breed used for milk and meat production. This breed was developed in England and is a composite of dairy goat breeds from India, Europe and Africa. Brought into the USA at the beginning of this century, the Nubian has become the most popular US dairy goat breed, with over 100,000 registered breeding stock.

Pygmy

The Pygmy is a dwarf, heavily muscled and short legged goat from Nigeria in West Africa. The Pygmy found its way to the Caribbean and North America as a by-product of the slave trade in the 18th century. In West Africa, the Pygmy is used almost exclusively for meat production. The pygmy is well adapted to humid climates, it usually breeds all year and twinning is frequent. In the USA, the Pygmy has so far been raised mainly as a pet and over 30,000 animals are currently registered with the National Pygmy Goat Association. The Piedmont Pygmy Goat club has three sanctioned shows a year, the NC Fair Pygmy Goat Show and two other shows held at the Agricultural Barn in Greensboro in spring and fall.

Kiko

The Kiko was developed over two decades of intensive selection from New Zealand feral goatstock. The Kiko is thought to be a vigorous, hardy, large frame, and early maturing animal that doesn't need pampering.

PRODUCTION TRAITS

Four key traits to be considered for genetic improvement in goats used primarily for meat production are the following: 1) adaptability to environmental and production conditions, 2) reproductive rate, 3) gross rate and 4) carcass characteristics. Of these four production traits, only carcass characteristics are not readily measurable on the farm. With good record keeping and a set of scales, the meat goat producer can collect the information needed to measurably increase the productivity of his/her meat goat enterprise.

Adaptability

This trait is the most important of all the reproduction traits. The profitability of any meat goat enterprise may be greatly diminished if an animal's ability to survive and reproduce is impaired by the production environment. The goat has proven to be perhaps the most adaptable of all the domesticated livestock. Indeed, the goat survives worldwide in a wide range of environmental conditions. However, when taken out of one environment and placed into another, domesticated livestock may not always realize its production potential. Therefore, we might expect Spanish goats to perform differently in the Carolinas and Virginia than they do on the arid Edwards Plateau of Texas. Similarly, Boer goats might perform differently in South African then they do in North American. In addition, different degrees of adaptability exist between breeds. For example, we might expect Spanish goats to be inherently better adapted to extensive, browsing conditions than Tennessee Stiff-leg goats.

Adaptability is a lowly heritable trait because natural selection has already reduced the genetic variability. Therefore, adaptability will respond slowly to selection.

Reproductive rate

In animals kept primarily for meat production, reproductive rate is the single most important factor contributing to the efficiency of production. Reproductive traits of interest in meat goat enterprise would be conception rate, kidding rate, and ability to breed out of season.

In general, goats have a high reproductive rate with conception rate not being a problem. Several studies have demonstrated that although twins and triplets have no lower birth and weaning weights have slower growth rates, they produce more total weight of kid per doe per year. Therefore, prolificacy, defined as the number of kids born per doe, is an important reproduction trait. Goats that have evolved in the temperature zones of the world tend to be seasonal breeders, with females coming into estrus in the fall and anestrus occurring in late spring. This breeding pattern does not always coincide with the optimal marketing period of weaned kids. On the other hand, goats from tropical regions are non-seasonal breeders and kid all year-round. Therefore, incorporating this trait of non-seasonality into a meat goat enterprise would be advantageous.

Growth rate

Growth rate can be effectively divided into two periods: pre-weaning average daily gain and post-weaning average daily gain. A high pre-weaning average daily gain not only reflects the genetic potentiall of the growing animal, but also the mothering ability of the doe. In some production systems, kids are sold at weaning and therefore pre-weaning average daily gain is an important production trait to consider. In other production systems kids are sold as yearlings or as older animals and post-weaning average daily gain becomes an important production factor.

Carcass characteristics

Carcass characteristics of interest are dressing percentage, anatomical distribution of muscle and the ratios of lean:fat:bone. Generally, the dressing percentage of goats is around 50%. As an animal grows, the percentage of fat in the carcass tends to increase, the percentage of bone tends to decrease whereas the percentage of lean muscle stays about the same. The portions of the carcass with the largest muscle mass are the leg and shoulder. However, percentage wise, these portions tend to decrease as the animal grows.