Overview of Health-Management Interaction: Goats
Management of goats depends on the type (eg, dairy, pygmy, meat, mohair, or cashmere) and the reasons for which they are kept (eg, companionship or commercial enterprise). However, all are ruminants, and the basic principles of livestock husbandry are applicable. Dairy goats and pygmies are often raised intensively, with most of the feed being brought to the animals. Meat goats and fiber goats are usually raised extensively, with most of the diet coming from browse and occasionally from high-quality pasture at times of highest nutritional need, such as the last 6 wk of gestation and the first 18 mo of life. A pregnant Angora doe without adequate energy and protein continues to grow mohair, even if stressed until she aborts.
Of all farm animals, goats have the strongest social hierarchy; thus, adequate feeder space or pasture should be provided so the dominant animals cannot guard feed and prevent others from eating. The amount of floor space available per doe affects the amount of aggressive behavior. A goat can become so subordinated to its penmates that it does not eat and loses condition. This behavioral component must be considered in cases of wasting goats. To maximize longevity and to avoid fighting injuries, adult males should be fed and housed individually, especially during the breeding season when fighting increases. If group penned, bucks should be kept together and given time to get to know each other before breeding season begins. Introducing a new buck to a pen of existing bucks during breeding season may result in injury or death.
Goats are adventurous and are natural climbers, and efforts to control them are necessary. The ultimate control would be high-tensile, electric fences; goats stand and push on other fences and can be very destructive. Hazards that might contribute to broken legs and strangulations should be removed. Tethering goats is potentially dangerous, because they are vulnerable to dog attacks; also, if two goats are chained too close to each other, one might strangle. Chafing of ropes too tight on the neck can lead to deep abrasions and tetanus. Because goats chew on painted surfaces, lead poisoning is a potential hazard in old barns. An efficient layout of pens, easy access to well-designed feeders, and effective control of movement minimize management-related problems.
It is extremely difficult to keep goats’ feet, urine, and feces out of many types of grain feeders, hay racks, and waterers. Goats often refuse to eat soiled feed or water, hay that has fallen on the floor, and grain contaminated with urine or feces. Design of hay feeders is critical to reduce feed wastage. Many dairy and pygmy goats are bedded on wasted hay, but this practice may lead to an increase in parasitism. Wet bedding contributes to development of coccidiosis in kids and staphylococcal impetigo on the udder, commonly but erroneously known as “goatpox.” Under similar conditions, joint-ill (see Joint-ill in Goats) and navel infections of the newborn are likely. Separate, dry, well-bedded pens should be maintained for kidding. In certain areas, kids are susceptible to white muscle disease (see White Muscle Disease in Goats), which can be controlled by dietary selenium supplementation or by injection of vitamin E/selenium to the pregnant doe and/or newborn. Concerns about abortions associated with vitamin E/selenium injection in ewes have prompted caution about parenteral injection in pregnant does, and oral supplementation may be preferred.
Housing of goats affects disease patterns. Angoras in the southern and western USA are usually given access to shelter only during severe storms or for a few weeks after the twice-yearly shearing, without which they may die of cold weather stress. Goats in the northern USA are housed in the winter, perhaps more for the owners’ comfort than for optimal health of the goats. Combinations of manure packs, overhead hay-mows, or noninsulated ceilings lead to dampness and ammonia buildup, especially if the barn is closed tightly. Warm, wet, poorly ventilated barns are conducive to development of neonatal navel infections, mastitis, enteritis, pneumonia, and coccidiosis. Caseous lymphadenitis (the disease known as “abscesses”), caused by Corynebacterium pseudotuberculosis (ovis), spreads rapidly in closely confined goats (see Caseous Lymphadenitis of Sheep and Goats). The slow-growing, nonpainful lymph node abscesses eventually rupture and contaminate the feeders, walls, and other animals. Keyhole-style feeders and head catches on milking stands are prime sources of transmission, because they promote rupture of abscesses on the head and neck. The infection is spread by contact with the pus, and the organism can penetrate intact skin. Isolating affected goats, preferably culling them, and preventing environmental contamination is important. A commercial vaccine approved for goats is available, and autogenous bacterins have been used to decrease the incidence of these abscesses. Intensive management of adult goats may promote horizontal transmission of the virus that causes caprine arthritis and encephalitis (CAE, see Caprine Arthritis and Encephalitis).
Mature bucks develop a powerful, characteristic odor that is most intense in the breeding season, and personnel are reluctant to handle them. This often leads to neglect of feet, failure to recognize heavy parasite loads, or loss of body condition. The sebaceous glands on top of the head can be removed surgically at any age or can be cauterized at the time of disbudding; however, this does not render the buck totally odorless. Does are attracted by this smell and may refuse to be bred by a descented buck if there is an odoriferous one nearby; therefore, the glands should not be removed inadvertently at the time of disbudding if male kids are to be kept for breeding. The habit of urinating on the face, beard, and forelegs also contributes to buck odor and often leads to ulcerating sores in cold weather. During the breeding season, most bucks lose weight, although this is not necessarily due to breeding too many does. Many bucks lose weight when housed close to does in heat, even when breeding is not allowed. One management strategy is to ensure that bucks are in prime physical condition before the breeding season.
In the European dairy breeds, the genetically homozygous polled doe usually is anatomically an intersex and, therefore, infertile. Aberrations vary from a slightly enlarged clitoris visible only after puberty, to a buck-like conformation with a scrotum, penis (often shortened), and ovotestes. Some phenotypically male pseudohermaphrodites show male libido with breeding activity. Because these animals are infertile, early recognition and culling is advisable. Some homozygous polled males may be able to sire kids, but these bucks are likely to develop sperm granulomas as they mature and should be culled rather than used for breeding. Most owners reduce the incidence of homozygous polled animals by never mating two polled animals. While most intersex goats are polled, similar anatomic aberrations are seen occasionally in horned goats. These would most probably be chimeras (freemartins), the result of anastomoses developing in utero between males and females. Such chimeras in goats are rare (considering the high frequency of twins) when compared with cattle.
For foot care, see Lameness in Goats.