Hair Goat Herd Health Management and Preventive Medicine

The Angora goat is the source of the valued textile fiber mohair. Three main areas of mohair production in the world are the Anatolian plain of Turkey, where the Angora goat originated, the bushveld of the Karoo dis­trict of South Africa, and the Edwards Plateau region of Texas in the United States.

Mohair production is a rather specialized agricultural enterprise, and an overall discussion of the industry is beyond the scope of this text. A good review of goat fiber production has been published (Shelton 1981). Health and reproductive problems related to fiber-producing goats in North America have been reviewed (Bretzlaff 1990). A his­tory of the mohair industry in South Africa is available (van der Westhuysen et al. 1988), as is an overview of the health problems commonly seen in South African Angora goats (van Tonder 1975). A guide for mohair production under intensive management in cold climates is available (Drummond 1985). There is an informative book on the goat fiber industry in New Zealand (Yerex 1986) and a good review of husbandry practices in the Australian Angora industry (Evans 1980). In addition, there is much current information available on the internet from extension ser­vices and producer associations regarding management of Angora goats in various countries, including different regions of the United States.

One aspect of fiber production in goats rather unique to Australia and New Zealand is the capture and use of feral goats for crossing with Angoras to rapidly expand fiber production capacity in the face of limited access to pure­bred breeding stock. Feral goats, which tend to dwell in the mountainous regions of these countries, have a significant amount of hair that qualifies as cashmere on the basis of fiber diameter. The fiber from crossbred goats is known as cashgora.

The Cashmere goat, also known as the Kashmir or Pashmina goat, is the source of the textile fiber cashmere. As the name implies, the goat originated in the mountain­ous region of central Asia. The finest cashmere commer­cially available still comes from traditional sources in Mongolia and China. Coarser grades of cashmere have also been available in commercial quantities from Afghanistan, Iran, and the former Soviet Union. The remoteness of these regions from milling centers in Europe and North America, coupled with political insta­bilities in the region, has created increased demand for cashmere from other sources. As a result, nascent cash­mere industries have developed primarily in Australia and New Zealand, but also in Europe and North America. Embryo transfer technology has played a significant role in the spread of cashmere production outside of traditional regions.

General Comments about Herd Health Management in Fiber-Producing Goats

Angora goats have a strong flocking instinct and a hierar­chical social structure. The flock readily follows lead goats that can be trained to come by banging a grain bucket. Angoras do not respond well to herding dogs, especially if the dogs work in too close, in which case the flock may become disrupted and scatter. If goats and sheep are com­mingled and disturbed, sheep move downhill and goats uphill. Angoras do not readily jump fences, but assuredly find holes to go through or depressions to slide under. Fencing must therefore be kept in good repair.

At range, wethers should be kept separately from does and doelings because the wethers are more active and mobile. Females may follow and spend too much time traveling and not enough eating.

Fiber and Fleece Characteristics

The attractiveness of mohair and cashmere as textile fib - ers lies primarily in the fineness of the hair. These hairs represent the “down” or insulating undercoat of the goat produced by secondary hair follicles. The characteristics of the fibers are discussed in detail in Chapter 2. The quality of the fleece and its economic value are affected by a number of faults, including a high presence of “kemp” or guard hairs arising from the primary follicles; the pres­ence of non-white fibers; contamination with plastic twine fibers, inks, marks, or dyes related to husbandry practices such as breeding harnesses; and the presence of vegetable matter such as seed heads and burrs. This latter must be controlled by timing shearing to precede the development of seeds and burrs on pasture or range. Carbonization, a process used to remove vegetable matter from a sheep fleece after shearing, damages the more deli­cate mohair fleece.

Shearing

Mohair grows at a rate of about 2.5 cm/month. The length of one year's growth, about 30 cm, presents process­ing and manufacturing problems, and Angora goats are usually shorn two, sometimes three, times a year. Kids, yearlings, and adults should be grouped and sheared sep­arately, and fleeces sorted separately. The younger the goat, the finer the fiber diameter. Sheep shears can be used, but should be run at a slower speed (1500 rpm). A 20-tooth goat comb head should be used. Various shear­ing techniques are used successfully in goats, including laying the animal down with the feet tied, standing the animal in a head catch, or tipping the animal up on its rump.

Cashmere goats shed their cashmere down or under - coat in the spring of the year. Traditionally, the down has been harvested by combing out the shed fibers from the haircoat. Cashmere goats can be sheared, however, and the guard hairs separated from the down at pro - cessing. Cashmere goats are sheared once a year in the spring.

The timing of shearing is an important issue in fiber pro­duction and animal health. Stress associated with shearing and the increased susceptibility to cold stress after shearing can lead to abortions or death losses in does, as discussed in Chapter 2. This is one reason that wethers are consid­ered desirable for mohair production. Windbreakers have been designed for shorn goats and may be applied to valu­able breeding stock, but their use in large commercial flocks is not practical.

Nutrition

The nutritional demands of fiber production are very high, especially with regard to protein. Yet, compared with sheep, the body size of fiber-producing goats is smaller, and their feed intake capacity is less. In does, gestation may increase nutritional demands beyond maintenance and hair production to the point that abortions readily occur.

Similarly, borderline nutritional status at breeding time may diminish prolificacy, leading to reduced kid crops. This is of particular importance in Angora goats because young animals produce better-quality fiber. Both male and female kids are used for production and the mean age of herds is kept young. Small kid crops make this difficult to accomplish.

Finally, future fiber yields appear to depend on adequate nutrition to the fetus in late gestation and to the newborn kid.

To address these various management and production issues related to nutrition, does should receive supplemen­tal feeding for four weeks before mating, four weeks before kidding, and four weeks after kidding.

Hair cover on the face is a common fault in Angora goats. Under extensive management conditions, impaired vision associated with facial hair can limit feed intake, with adverse consequences. Ideally, breeding programs should select against facial hair, but a positive correlation between facial hair and total fleece weight limits this approach.

Reproductive Problems

Fiber-producing goats are seasonal breeders, with estrus beginning in the late summer/early autumn with decreas­ing day length. Poor reproductive performance, as mani­fested by low ovulation rates and reduced fecundity, is correlated with small body size in Angora does. As men­tioned above, supplemental feeding, or flushing, of does may improve ovulation rates and prolificacy.

In addition to the broad range of infectious and non- infectious causes of abortion affecting other types of goats, Angora does are particularly susceptible to stress-induced abortion caused by cold temperatures, marginal or inade­quate nutrition, and poor condition associated with para­sitism. Good management is aimed at providing adequate shelter, nutrition, and parasite control. The frequency of abortion in Angora does increases as mohair production increases relative to body size.

A costly, inherited abortion syndrome of Angora goats associated with adrenal insufficiency occurs in South African Angoras. It is discussed in Chapter 13.

Cryptorchidism is common in Angora males. Such indi­viduals should not be used for breeding. Overworking bucks should be avoided. Depending on nutritional status, health status, topography, and distance, the buck-to-doe ratio should be between 1 : 25 and 1 : 75.

Mothering

Angora does kidding at pasture or range have a distinctly different mothering pattern than sheep. Producers familiar with sheep and new to goats may not recognize this. The doe “plants” her newly born kid, leaving it camped by itself or with other kids while the doe goes off to graze. It returns to feed the kid in the afternoon. Though planting behavior is natural for goats, it increases the susceptibility of kids to predation. When predation is a problem, does should kid in areas where woods or rock formations allow some camou­flage or protection for the kids.

Because dams spend a good deal of time away from their kids, early, strong bonding between dam and kid is very important to ensure proper recognition and nurturing of kids. To accomplish this, the pair need a critical five min­utes of undisturbed contact after birth. Therefore, it is essential that the kidding process not be disturbed by human intervention. Foraging does return to protect their kids if the kids issue a distress call. To take advantage of this behavior, does should kid on somewhat restricted and familiar foraging grounds so they can readily find and return to their kids. Gradually, kids begin to follow does on their foraging forays and the goats can be moved to larger pastures.

Newborn kids, especially those of low bodyweight, can freeze to death easily. Providing shelter may be necessary when inclement or cold weather occurs in conjunction with kidding.

Dehorning, Castration, and Marking

Horns are a mixed blessing on fiber-producing goats. Under extensive management, they may help goats defend them­selves against predators, but the more common result of horns is increased fighting among horned goats. Horns also increase the risk of goats becoming trapped in fences, espe­cially mesh fences. Under intensive management, horns increase the requirement for bunk space and promote acci­dents and injuries. Angora kids can be disbudded by elec­trocautery at 2-3 weeks of age. Horns on mature goats can be cut back with a hacksaw, as described in Chapter 18. Intact horns are favored in show goats and breeding stock.

Open castration, elastrator bands, or clamping can be used. The time of castration is variable. In Texas, castration of buck kids is often delayed until 1 year of age to ensure good sturdy horn growth for defense against predators. In Australia, goats are routinely castrated at 4-6 weeks of age. On humane grounds, elastrator bands should not be used in kids over 3 weeks of age without adequate systemic and local analgesia at the time of banding.

For improved record keeping and management, goats need to be identified. Ear tattoos are useful for perma­nent identification and are indicated for breeding stock. However, tattoos do not allow easy recognition of indi­vidual goats from afar. Ear tags are preferred for this pur­pose, but certain considerations apply. Any tag placed on the edge of the ear will readily tear out, especially metal tags. Penetrating, round button, flexible plastic ear tags are preferred, placed through the center of the ear. Some of these button-type tags are now also incorporating radi­ofrequency identification (RFID) technology. Tagging is best delayed until 4-6 weeks of age. Ear notching and horn branding are alternative methods of identification.

Parasitism

Fiber-producing goats are particularly sensitive to the adverse effects of gastrointestinal parasitism. The increased nutritional demand of hair production coupled with the limited feed intake allowed by their diminutive body size demands efficient use of nutrients for preserving health and productivity. The hypoproteinemia and blood loss associated with gastrointestinal parasitism can tip the nutritional balance against the doe, causing decreased fer­tility, abortion, increased susceptibility to disease, or out­right death. Pasture management and strategic and tactical treatments with anthelmintic are integral parts of Angora goat management. Parasite control practices are discussed in Chapter 10.

Even though fiber-producing goats are usually managed extensively, there are times such as weaning, shearing, bad weather, and supplemental feeding when flocks are con­gregated in confined areas. This increases the risk of clini­cal coccidiosis in kids and weanlings. Conscientious attention to sanitation and hygiene is required to manage this problem, along with the possible use of coccidiostats, as discussed in Chapter 10.

Lice and keds are more than a nuisance on fiber­producing goats. They can cause itching, rubbing, and sub­sequent damage to the haircoat, as well as anemia. In cashmere goats, louse egg cases clinging to hair can alter the dyeing characteristics of the fiber. Routine louse con­trol should be practiced, as discussed in Chapter 2. Some pour-ons may stain the fleece. If sprays or dips are used, it is important that goats not be chilled when wet.

Other Disease Problems

Soremouth (contagious ecthyma) is common in fiber­producing goats. Affected kids may have difficulty nursing and does may contract mastitis if teat openings are compromised by soremouth lesions. In extensive management systems in which bottle- or tube-feeding is impractical, kid losses can result. Vaccination is indi­cated. Foot rot and foot scald occur, but less frequently than in sheep. Preventive measures are discussed in Chapter 4. Fly strike also occurs in fiber goats, but less commonly than in sheep.

Wethers are extremely susceptible to the formation of urinary calculi and development of obstructive urolithia­sis. The calculi are most often composed of phosphate salts and the main approach to control is to ensure a proper ratio of calcium to phosphorus in the overall ration, as discussed in Chapter 12. Delayed castration can also reduce the risk of obstructive urolithiasis, as it allows for the urethra to develop a larger diameter under the influ­ence of testosterone, thus rendering it less likely to trap formed calculi.

Caseous lymphadenitis can be a serious problem in fiber-producing goats. As in sheep, the main route of transmission is through shearing, when cuts and abra­sions in the skin are inoculated with bacteria from open abscesses on other sheared goats. The shearing equip - ment acts as a mechanical vector. Shearers must be knowledgeable about the disease and disinfect instru­ments between goats. Young, uninfected goats should be shorn first.

Pneumonia is a common occurrence in weanling goats and is exacerbated by changing, adverse weather or by housing, if ventilation is poor. Access to shelter in wet weather helps to reduce the incidence of pneumonia. Early recognition and mass medication are critical in control­ling losses.

Hair goat breeds are susceptible to CAE virus infection. However, the prevalence of the disease is dramatically lower than in dairy goats. More must be learned about the epidemiology of CAE virus infection in hair goat breeds. At present, it is probably inadvisable to commin­gle hair goats with dairy goats. Milk or colostrum from dairy goats should not be used to raise orphaned hair goat kids, unless the source herd is certified CAE free or the milk and colostrum have been properly heat treated to kill the virus.

As with dairy goats, the minimum vaccination program should include C. perfringens types C and D combined with tetanus prophylaxis. In low-lying pasture areas, multiva­lent clostridial vaccines including protection against black­leg may be indicated. In selenium-deficient areas, does should be drenched or injected with sodium selenite just before mating and again two to three weeks before kidding.

A herd health calendar for hair goat production is given in Table 20.2.

Table 20.2 Herd health management and preventive medicine calendar for fiber-producing goats in North America.

Season Preventive activities

July and Check all goats for lice and if present, treat

August twice, two weeks apart

Deworm spring kids

Vaccinate all goats for enterotoxemia

Begin supplemental feeding (flushing) of does to be bred

Ensure adequate number and quality of breeding bucks

Turn teaser bucks in with does if synchronized breeding is desired

Begin fall shearing

September Begin breeding; use marking harness and keep and October records

Check goats for parasites; deworm and delouse as needed

Check and trim feet

November and December

Remove bucks from bred does

Perform pregnancy checks

Select rested pastures for kidding

Ensure adequate shelter facilities on kidding pastures

Begin preparations for indoor kidding, if an option

January and Begin spring shearing; shear pregnant does three February to six weeks prior to kidding; delouse goats after shearing

Boost feed levels to does due to kid four weeks prior to kidding date

Deworm and vaccinate does two to three weeks before kidding

Turn does out to kidding pastures to familiarize them with the pastures

When kidding begins, keep accurate records of kidding activities

March and Vaccinate kids at 4 weeks of age for

April enterotoxemia, tetanus, and, if present in the herd, soremouth

May and June

Place ear tags in goats at 4-6 weeks of age

Continue supplemental feeding of does for four weeks after kidding

When kids are following does, deworm goats and turn out from kidding pastures to larger grazing areas; but leave some adults in the best condition untreated, to provide a source of refugia

Wean kids and move them to a clean pasture with minimum parasite load

Plan to cull does for poor health or poor reproductive performance