The Australian feral goat : basis for a new industry?

Abstract

Animal Production in Australia THE AUSTRALIAN FERAL GOAT - BASIS FOR A NEW INDUSTRY? INTRODUCTION B.J. RESTALL* Goats may have been introduced into Australia by Dutch mariners in the 17th century, either from shipwrecks or as deliberate releases to aid future shipwrecked mariners, The first fleeters brought goats and almost certainly introductions were made illegally from Asia and Africa by the early traders. Various acclimatisation societies and individuals introduced Angora, and cashmere type goats, some of which ultimately found their way into the Their descendants have thrived and have been described as a healthy, fecund fit population whose size is variously estimated to be between one half and million individuals. They present to us a gene pool possibly unique in the dairy wild. and five world. Although these animals have been harvested for meat export since the early 195Os, serious studies of the feral population only began in the mid 1970s. These studies have shown that the feral goat has fleece, flesh and skin suitable for development for commercial exploitation. Recent changes in the world supply pattern of cashmere fibre, has led to an intense commercial effort by a major textile processor from the U.K. to establish a cashmere industry in Australia. Other textile processors are known to be interested in the feral goat down. These developments indicate that Australia is poised to begin a new animal industry based on the feral goat. It is timely to assess its characteristics and its potential. CURRENT EXPLOITATION OF THE FERAL GOAT T.D. MITCHELL** Little published information exists on either the biology or environmental impact of feral goats in mainland Australia. The information published k-g. Holst and Pym 1977; Smith et al. 1973) indicates that feral goats are able to produce usable quantities of meat and/or fibre. Studies on environmental impact are being carried out in at least two environments (Henzell pers. comm.; Mahood (deceased) pers. comm.). Others, for example Harrington (1979), Kajons and Holst (1977), have provided data on environmental effects of domesticated goats of feral origin in some locations. There is little argument that uncontrolled feral goats can damage an environment, are a risk in the event of an exotic disease outbreak and are a nuisance to pastoral area managers. Control and management of feral goats, is essential for proper environmental management, disease control and utilization of goat products. * N.S.W. Department of Agriculture, Agricultural Research Centre, Wollongbar, N.S.W. 2480. ** N.S.W. Department of Agriculture, P.O. Box 865, Dubbo, N.S.W. 2830. 130 Animal Production in Australia CURRENT USES Feral goats have been an important resource which has supplied animals for breeding and for slaughter. Most animals that are harvested are moved into other areas rather than maintained in their original environment. For breeding purposes, sound does have been selected from harvested ferals, subjected to a domestication process and then used as either 'foundation' does in Angora grading-up programmes or for control of weeds in definable circumstances. More recently, interest in down production has emerged, for which goats of feral origin are the genetic resource. Flocks of down bearing goats have been established and animals with more or less down producing ability are being selected from within flocks. A research project (see Paper 2) at the Agricultural Research and Advisory Station, Condobolin, has shown that goats of feral origin can be managed and bred to become efficient meat producers. Goats have long been recognised as able to control many woody weeds and recent studies have shown that goats will control serrated tussock (NasseZZa trichotoma>, (Campbell et al. 1979) and blackberries (Rubus ~z?&cosus), (Vere and Holst 1979). Observations have been recorded by Holst et al. (1978) of many other weed species being consumed and/or controlled by goats. Near Orange, the N.S.W. Forestry Commission is running goats on ?kLYS Padiata forest floors to control weed growth (Edwards 1981). EXPORTS Of all goat commodities exported from Australia, meat has been the greatest earner. Most of this produce has been derived from goats harvested from feral flocks in semi-arid pastoral areas. Table 1 shows the numbers slaughtered in export licensed abattoirs in recent years. Western Australia has been the largest source of animals and meat. There is considerable movement of live animals for slaughter between eastern states, so that it is difficult to relate the state of origin of live animals to numbers slaughtered. TABLE 1 Numbers of goats slaughtered at licensed abattoirs (Source: A.M.L.C.) The total weight of goat meat exported from Australia and its value, have continued to increase (Table 2). If the value of exports is divided by the weight, an indication of value per tonne F.O.B. is calculated. This figure indicates that the unit value of goat meat exports has also increased. 131 Animal Production in Australia TABLE 2 Total amount and value of goat meat (chilled and frozen) exports (Source: A.B,S.) Live animals for slaughter are also being exported in increasing numbers. Unfortunately, harvested goats are not usually selectively culled, that is there is no attempt to retain sound females for breeding while others are sent to slaughter and kids returned to the wild to grow. If does are retained, it is usually in response to particular orders or that they are mustered by their future owners for that reason. Harvesters are more usually involved in catching goats for slaughter. If an animal is big enough, that is over about 10 kg dressed weight, and able to walk onto a truck, it is sent to slaughter. The product of this process must be of variable quality as the animals themselves vary from aged bucks to buck kids, from aged does to doe kids that may be in any physiological state. The animals can be difficult to skin, old bucks have an offensive odour and condemnations of either part or whole carcases is relatively common. Feral goats have also been implicated in the incidence of Q-fever in employees in some abattoirs. Grading of carcases from feral goats is usually done on a weight basis. Some markets,' like Singapore, prefer carcases over 18 kg; while others, like Malaysia prefer carcases below 18 kg (Anon. 1980). There is no age, sex or condition classification for the export carcase trade. There is a need to develop these classifications for the local meat trade. Skins are a potentially valuable by-product, but are also of variable quality. Age I sex and lack of management affect scarring, bruising, external parasite infestation, and fat deposition. Skin quality is also affected by flailing and treatment once removed, No attempt is usually made to grade skins for size, quality or any other reason, These factors combine to ensure that skins from feral goats receive low prices. Trials by Holst (pers. comm.) indicate that skins from domesticated and managed feral goats are of a more consistent and higher quality, and are thus of greater value. LEGISLATION Attitudes and thus laws towards feral goats differ between states, although in all states there is concern about the effects of uncontrolled feral animals. In Western Australia, 'wild' goats are declared noxious; in South Australia uncontrolled feral goats might be declared noxious (Henzell pers. comm.); while in New South Wales goats have recently been included within the Pastures Protection Act with managers being encouraged to control and manage feral flocks. Attitudes in Queensland and Victoria are unknown. 132 Animal Production in Australia The West Australian Department of Agriculture have begun a down bearing goat breeding project using harvested feral goats. This project may lead to alterations to existing legislation that would allow producers to maintain husbanded flocks of goats in pastoral areas. Similarly, the legislation that is likely in South Australia may allow husbanded flocks of goats to be run in pastoral areas. At this time, while official attitude does not agree with allowing feral animals to roam free, most agencies are becoming aware that the present uncontrolled feral goats may be a valuable source of new products and that they may also have some value in management of our pastoral areas (Mitchell 1977). FUTURE There is a need to assess the relative worth of our feral goat flocks. We have seen them used as foundation animals in Angora grading-up, and we know that they can produce meat and fibre in their own right. Their role in environmental management has not been studied exhaustively, but they have been shown to be of worth in the management of some weeds. An assessment of the phenotypic characters of feral goats is essential to assess their genetic worth for at least meat and down production. The need is urgent, as there is little doubt that the current rate of harvest is above the level of recruitment (Henzell pers. comm.). SUITABILITY FOR GOAT MEAT AND SKIN PRODUCTION P.J. HOLST*, R.A. PYM** and P.J. NICHOLLS*** GOAT MEAT AND MARKETS The meat from goats is a preferred meat in many countries, especially in Africa and Asia where it is not only a traditional meat, but also has a particular value in that there are no known religious taboos against it (Holst and Whitelaw 1980). Goat meat exports from Australia were initiated in 1952 and for the past three years have been approximately 3500 tonnes/year (A.M.L.C.), As a generalization, goat meat is exported to reliable traditional markets such as Malaysia, West Indies etc., to manufacturing meat markets such as the United States, and to erratic markets such as the middle east. That most of this meat was derived from feral goats might suggest that the feral goat is suitable for the export market. While this may be true, the successful export of the meat is dependent on the entrepreneural skills of the exporter, on competitive pricing (relative to mutton) and differences in the requirements of sections of the market that facilitates the utilization of a variable product (i.e. mixed sex, weight and fat cover). The potential for a domestic market for carcase goat meat has not been identified. Without a reliable supply of quality carcases, it is a difficult exercise but the table, restaurant and providoring outlets would suggest that it is significant. The current (since 1981) supply of carcase meat to the Sydney and Canberra markets meets a steady demand for the limited number of carcases available. Carcases of lo-12 kg with some fat cover are in particular demand. * N.S.W. N.S.W. ** N.S.W. Seven *** N.S.W. Department of 2794. Department of Hills, N.S.W. Department of Agriculture, Agricultural Research Station, Cowra, Agriculture, Poultry Research and Advisory Station, 2147, Agriculture, Biometrical Branch, Sydney, N.S.W. 2000. 133 Animal Production in Australia EFFICIENT MEAT PRODUCTION Factors that have to be considered in meat production are reproductive efficiency, growth rates and the potential for genetic improvement, Reports on fertility (Holst and Pym 1977; Holst 1981; Harrington 1982) and growth rates (Holst and Pym 1977; Hancock, Phillips and Sabine 1979) for the feral and domesticated goat suggest that the feral goat has an outstanding potential to produce meat efficiently. Potential for genetic improvement There are two main genetic avenues for improving meat production in the feral goat. The first method is to select within existing stock for improved growth rate to slaughter age and the second is to upgrade by crossbreeding with a breed showing superior performance. There is a dearth of information on genetic parameters associated with growth in the goat and to provide this much needed information on the Australian feral goat a selection experiment was initiated by the N.S.W. Department of Agriculture at Condobolin in 1974. Selection was for increased liveweight at 5 months of age adjusted for birth and rearing types and age of dam. The realised heritability of 5 month liveweight calculated in the 1976 drop kids was 0.35 + 0.15. This agrees with the few published heritability estimates of liveweight at about this age in goats ,and with the majority of estimates in sheep. Thus selection for improved liveweight at slaughter should yield reasonable response. The main problem limiting gains in this area is the necessity for accurate correction factors for age, birth and rearing types and dam age (Pym, Holst and Nicholls 1982). As an indication of the performance of the goats in the feral breeding programme, average liveweights of 1977 drop twin progeny from non-maiden does are shown in the table below. Selection commenced in 1975 and was only exercised in the males. Weaning and 5 month weight were corrected for age. Weaning was at about 13 weeks. TABLE 3 Average liveweights of 1977 drop twin progeny from nonmaiden does in the selected and control lines Perhaps the simplest and quickest means of making genetic improvement in livestock is to cross with a superior breed. One major problem in Australia is that breeds possibly superior to the feral goat in growth and meat characteristics are few and those that are present have a very narrow genetic base and are highly inbred. An evaluation of the Anglo Nubian breed as a means of upgrading the growth and carcase characteristics of feral goats was commenced at Condobolin in 1975. Preliminary results indicated that the Anglo Nubian x feral first cross animals were some 3 kg heavier at 5 months of age than their feral parents and the Fl x Anglo Nubian parent backcross were about 4 kg heavier than the ferals. The main problem in this evaluation was the impossibility of obtaining objective data on the performance of the Anglo Nubian parent breed and the small number of males of that breed that could be used in the study. 134 Animal Production in Australia Notwithstanding these limitations, the results to date indicate that there may be considerable potential in the industry for the male progeny produced by backcrossing the Fl crossbred doe to Anglo Nubian bucks. It should be possible to generate reasonably large numbers of these 3/4 Anglo Nubian bucks and the performance of the commercial progeny produced from mating these animals to feral does would in all probability be fairly similar to that of first cross animals. One possible implication of such a move may be to have an undesirable influence upon the fleece characteristics of the feral goat. Work is in progress to obtain more comprehensive genetic parameter estimates from the feral selection experiment and to more precisely evaluate the potential of the Anglo Nubian in upgrading programmes. LEATHER Australia exports 300 tonnes of goat essentially all the feral goats slaughtered skins has not been great and in the absence returns to the producer have been minimal. been graded prior to sale/export. skins annually and this in the country. Demand of a domestic goat skin Most of the skins would represents for these industry, not have Factors affecting the quality of a skin include the following: pre slaughter slaughter preservation grading damage from ectoparasites, fences, transport careless flaying no trimming, often air dried not graded nor sorted into single lines based on sex, age, hair, etc. It is not unusual for all of the above factors to be operating and thus even a potential1 y good quality skin will be damaged. Yet, all of the above factors can be solved by adopting known management techniques and because the skins are usually structurely sound, with care, they could have been valuable. Top quality, finely grained leather is used for shoe uppers, gloves, etc. Other poorly grained but sound leather is in demand for luggage, shoe linings, book covers, etc. Holst (1982) concluded that the skins were basically sound and that considerable scope existed for improving leather quality by altering management and processing procedures. He noted the acceptable grain fineness of some skins was related to density of primary follicles (Np) and skin surface area. He proposed selection criteria and methods for the genetic improvement/maintenance of the skin quality for leather purposes of these goats. Factors included density of primary follicles, guard hair length, diameter and follicle depth, Rendel and May objectives in sheep. goats (Turner 1982) could be achieved in grown, fertile goat (1978) showed that it was possible to achieve these In view of similarity in other traits between sheep and it is reasonable to expect that these selection objectives goats as well. The meat/skin goat could then be a well with dense fine, short guard hair with shallow follicles. 135 Animal Production in Australia GENETIC IMPROVEMENT FOR DOWN PRODUCTION B.J. RESTALL Since the first recognition that at least some of the Australian feral goats grew a fine down similar to cashmere (Smith, Clarke and Turner 1973), a small number of breeders have been attempting to improve down production from selected feral animals. In 1981, a large cashmere processor issued a buying schedule that gave a premium for white down of 15/16 1-1 diameter, with coarser and colored fibres being discounted. The 1982 price schedules have increased these differentials giving breeders clear production goals. Further impetus to this infant industry has come from commercial promotions that indicate that 1000 tonne of down is required by one UK processor alone (Dawson International 1981). These developments have led to a demand for information on breeding for increased down production. Breeding for improved production implies that there are clearly defined breeding goals, and breeding plans based on a knowledge of the production parameters of the goat. Unfortunately, we lack any systematic study of the genetics of down production in our goats, and indeed have only fragmentary data on the fleece characteristics and their variation in the feral population, Nevertheless, provisional breeding plans are required now, and these must be necessarily based on extrapolation from other sources until we have completed our own systematic studies. Down production in our goats will be a function of the down bearing surface area, the density of down fibres per unit area, the diameter of the fibre (related to cross-sectional area), the length of the fibre and its specific gravity. The successful manipulation of these components to improve down quantity and maintain quality requires a knowledge of the relative importance of the components, their variability, heritability, and the genetic and phenotypic correlations between them. The situation with the goat is complicated because it has two coats. The biological and genetical relationships between the two are unknown, but may be of practical importance if, for example, the hair coat protects the downy undercoat from damage. GENETIC STUDIES WITH DOWN BEARING GOATS For some 50 years selection and crossbreeding studies with goats have been carried out in the USSR. Reports of this work appearing in Animal Breeding Abstracts have been reviewed (Restall, in preparation) and indicate that the components of down production are highly heritable. Increases in down weight due to selection have been substantial but generally are at the expense of fibre diameter. The use of the Angora to improve yields of white down have also resulted in an increase in fibre diameter. While genetic correlations are not reported it seems as if density and diameter may be negatively correlated as in the sheep. The current Soviet breeding policy appears to be selection for fine white down within the various indigenous strains. FLEECE CHARACTERISTICS OF THE AUSTRALIAN FERAL GOAT Smith e-6 al. (1973) suggested that 10 to 15 per cent of feral goats grew down with a mean diameter of 15.5 1-i and a mean length of 3.5 cm, i.e. within the 136 Animal Production in Australia limits for cashmere processing. Measurements on a number of groups of goats have extended these observations (Table 4). TABLE 4 Fleece characteristics of male feral goats originating in western N.S.W. Mean values and standard deviations (SD) The data show variability in total fleece weight, down weight and down diameter such that there is considerable scope for selection. Only limited data is available for female goats; in a group of 125 unselected feral does from western N.S.W., 90 (72%) were assessed as having commercially recoverable down. Samples of their fleeces showed a mean yield of 22.3 per cent (sd 7.7), a mean diameter of 15.8 p (sd 1.18) and a mean length of 3.38 cm (sd 0.84). The implications of these data for breeding plans are that it may be of value to spend considerable effort to locate males with superior down weights within the desired diameter range in order to obtain large selection differentials. Phenotypic correlations for some parameters in flocks B and C are given in Table 5. TABLE 5 Phenotypic correlations for some fleece parameters in male goats from two flocks 137 Animal Production in Australia The positive correlations between down weight, diameter and yield suggest that selection for down weight within a flock will result in an increase in the mean diameter of the selected animals. These correlations also suggest that the hair and down components of the fleece may be considered independently for the purpose of selection, and that selections will have to be based on the more expensive measures of down weight and diameter. Data component. 22.9 per sq per sq mm. the fleece are lacking for density of down fibres, the other important fleece Hoist (pers. comm,) has recorded a primary plus secondary density of mm; data from the USSR gives a density range of 21 to 30 follicles There is an urgent need for data on the genetic correlations between components, particularly that between density and down diameter. Provisional breeding plans for the improvement of down production should aim at producing white down with a mean diameter of 15.5 1-1. As heritabilities are likely to be moderate to high, selection based on independent culling levels for down weight and diameter should result in improvement of weight of down of the desired quality. It would be advisable to avoid the temptation to rapidly increase weights by allowing diameter to broaden, as it may be difficult to recover the fibre fineness without loss in weight in the future. A far better strategy is to hold diameter at the desired level and allow weight to increase through changes in density, length and body weight. To improve the probability of obtaining superior individuals, herd sizes should be as large as possible, and employ an open nucleus breeding system. Co-operative breeding schemes between breeders with agreed production goals could achieve such herd sizes. THE NUTRITION OF THE FERAL GOAT B.W. NORTON* The establishment of a goat industry producing meat and fibre in Australia will require basic information on the nutrient requirements of goats and on management practices necessary to optimise the selected form of production. Reliable information on the energy requirements of goats for maintenance and growth comes from the studies of Devendra (196i'a and b) with indigenous Malaysian goats (mature weight 25 kg), and the N-balance studies of Majumdar (1960a and b) with Jamnapari goats (31-44 kg) provide the only information on maintenance protein requirements. Little is known about the specific requirements for fibre growth or the mineral nutrition of the goat. Although any future goat industry in Australia will be based on systems, a critical assessment of nutrient requirements must involve pen-fed goats where feed intake ant-l quality are varied and related to characteristics. The broad genetic base of the Australian feral goat may provide ample scope for selection, but this variability may also difficulty in the precise description of the nutritional requirements animals. grazing studies with production population cause of these Table 6 shows mean values, range and coefficient of variation for some measurements of feed intake and utilization of a randomly selected population of feral goats offered a concentrate diet (17.9% crude protein, 38.6% NDF). *Department of Agriculture, University of Queensland, St. Lucia, Qld 4067. 138 Animal Production in Australia TABLE 6 Mean values, range and coefficients of variation for liveweight, feed intake, digestibility, live weight gain and fleece growth of male feral goats (n = 25) offered a concentrate diet These results demonstrate the likely variability associated with nutritional trials with feral goats, and in addition to this, approximately 20% of the goats used were excluded from these figures because of a persistent non parasitic diarrhoea. In this study, digestible organic matter (DOM) intake was significantly (P < 0.05) correlated with live weight gain (r = 0.84), and described by the following equation This equation indicates that the maintenance requirement of these goats (25.9 g DOM/kg 0.75/d> was similar to that reported by Devendra (1967a) for Malaysian goats (25.2 g DOM/kg 0.75/d) and not greatly different from sheep of similar weight (A.R.C. i965). The requirement for liveweight gain (3.1 g DOM/g gain) was also similar to that for growing lambs (Walker and Norton 1971a) suggesting that some similarities do exist between sheep and goats in dietary requirements. However, these preliminary observations need further confirmation because goats differ from sheep by having lower fleece growth rates at equivalent N intakes (Reis and Schinckel 1964; Walker and Norton 1971b), leaner carcases, seasonal patterns of fleece growth and probably higher requirements during pregnancy for the growth of multiple foetuses. The following areas of nutrition research require high priority if producer interests in the goat industry are to be met with factual information. Pregnancy and lactation The goat is a prolific breeder under feral conditions and reproductive activity may be related to prevailing nutritional conditions. Singh (1968) has demonstrated very poor reproductive performance in does restricted in energy intake, and does carrying multiple foetuses have high nutritive requirements in late pregnancy (Kalaissakis 1959). The effects of nutrition in this period on lactation performance also need careful study. The selection of goats for high growth rate from birth to weaning is essentially a selection of goats from dams with high milk yields. The relationship between pre- and post-natal nutrition of the doe on milk yield, composition and persistence will have a major effect on kid growth to weaning and hence on all aspects of productivity from goats in a commercial enterprise, 139 Animal Production in Australia Post weaning growth Yearly management systems for goats are yet to be determined, and specific information is required on optimum weaning times, and on the management of the post weaning kids. It is at this time that greatest nutritional stress applies to the growing kids, and from our experience growth rates during this period under a range of pasture conditions have been disappointingly low. Table 7 shows some mean values, range and coefficient of variation for the liveweight gain of feral kids we have recorded from goats grazing tropical pastures in the post weaning period. TABLE 7 Mean values, range and coefficient of variation (CV) for mean live weight (kg), live weight gain (g/d) of female feral goats in post-weaning period grazing different pastures * Figures in parentheses are number of goats When compared with pre-weaning growth rates, there has been a significant decrease despite treatment for intestinal parasites and supplementation with cobalt. However, growth rates markedly improved when goats grazed oats indicating firstly that compensatory weight gain occurs in these animals and secondly that a nutritional, rather than genetic factor was probably responsible for poor growth prior to this period. There is a need to raise kids to 25 kg by at least 18 months of age for both the maintenance of breeding flock numbers and for the turn off of animals suitable for slaughter. There is an urgent need to define the protein, energy and mineral requirements of goats in the post weaning period so that management practices may be developed to optimise the growth and productivity of goats during this time of maximum stress, Fibre production and nutrition There is presently no information on the relationship between fibre (cashmere) production and nutrition that can be reliably applied to the Australian feral goat. However, a number of areas of research can be readily identified from the extensive literature on wool growth in sheep. The initiation and development of secondary and primary follicles in utero needs intensive study, with particular attention to the relationship between maternal nutrition throughout follicle development and the effect that multiple foetuses has on this process. These studies must be extended into the post-natal period to determine the effects of nutrition on fibre production and on the development and ultimate maturity of secondary follicles during this time, The relationship between nutrition, live weight growth and fleece production also needs clarification. Does the selection of goats for high live weight gain during post-natal growth select against goats with high potential for fleece production? Alternatively, what penalty is paid in terms of fibre diameter (quality) when goats are liberally fed to maximise fleece growth? Cashmere production is seasonal, commencing in Jan\uary in our flock and being shed in August. The physiological factors affecting the 140 Animal Production in Australia initiation of growth and the stimulus to shedding, the effects of pregnancy and seasonal feed availability on cashmere growth must be determined before management strategies can be developed to optimise fleece production. IS THERE AN ECONOMIC FUTURE FOR FERAL GOAT EXPLOITATION? L. DAVIES* I have chosen to use the term bush goat to refer to a domesticated feral goat, and the term feral goat to goats in an unmanaged state. At present, bush and feral goats are utilised in four main ways: (1) (2) (3) (4) For the production of meat and skins. For use in Angora upgrading programmes. Using selected bush or feral goats for a cashmere enterprise. For use as a method of weed control. The long term use of bush goats in upgrading programmes (both Angora and cashmere) is unlikely. In an example Angora goat grading up programme (Mitchell 1978) no further bush goats were brought into the programme after year one. It is doubtful that there will be further demand for bush goats in Angora upgrading as new enteries into the industry are most likely to buy 1st or 2nd cross Angora does that have been culled from other flocks. There will be a short term demand for bush goats showing cashmere characteristics if a cashmere industry develops. The prospects for a developing cashmere industry are beyond the scope of this paper but Buffier and Gellatly (1981) and a recent publicity document by Dawson International indicated that returns should be comparable to sheep enterprises. However, demand for bush goats will only be short term and dependent on the ultimate size of the cashmere industry. In addition, demand for feral stock will be restricted to those showing cashmere characteristics and this could vary from 15 per cent of the herd to 60 per cent of the herd (Mitchell 1981 pers. comm,). WEED CONTROL Goats are most likely to be considered for weed control in areas where cultivation