Period of lot feeding of feral goats before live export by ship

Abstract

Proc. Aust. Soc. Anim. Prod. 1994 Vol. 20 PERIOD OF LOT-FEEDING OF FERAL GOATS BEFORE LIVE EXPORT BY SHIP S.G. GHERARDI and T.J. JOHNSON Sheep Industries Branch, Dept of Agriculture, South Perth, W.A. 6151 SUMMARY Feral goats were lot-fed for either 7 or 14 days before a simulated shipping voyage of 20 days, to examine whether period of lot-feeding affected the proportion of goats that ate pelleted feed and the subsequent liveweight changes. During the period from the start of lot-feeding to the completion of the simulated voyage, liveweight losses were similar and underestimated true losses because of the removal of goats which lost more than 20% of their initial liveweight to days 7 or 14 of simulated shipping. Also period of lot-feeding had no effect on either the proportion of non-feeders during the simulated voyage or the proportion of goats that completed the voyage. It was postulated that the failure of the goats to eat in the feedlot was a likely cause for their poor performance. The results of this study suggest that there was no advantage in increasing the period of lot-feeding of feral goats from 7 to 14 days. However, further studies are required to define the optimum period of lot-feeding of feral goats before live export by ship. Keywords: feral goats, lot-feeding, live export, shipping. INTRODUCTION The major markets into which goat carcases are sold from Western Australia (WA), that is the Caribbean and Taiwan, are extremely volatile, and the long-term prospects for this trade are unpredictable, but there is a potential to develop markets for live goats in both the Middle East and Asia (Toseland 1990). The development of these markets is hampered by the inability of Australian exporters to provide a consistent supply of a quality product. Goats, primarily of feral origin, suffer a big loss in liveweight and condition with mortalities during shipping of around 6% (R.T. Norris pers. comm.). There is no information on the causes of poor performances and mortalities of goats aboard ships. Goats are usually lot-fed for a period of 5 to 7 days before shippin g, during which they are fed the pelleted diet offered aboard ship. It is possible that this period of lot-feeding is too short for feral goats and may be contributing to poor performances. The experiment reported here examined the effect of 2 periods of lot-feeding on the proportion of 2 liveweight groups of feral goats that ate the pelleted feed offered, and on subsequent liveweight changes during lot-feeding and simulated shipping. This experiment was conducted prior to the introduction of the current regulations which require that feral goats be lot-fed for a period of 21 days before live export by ship (Australian Quarantine and Inspection Service 1992). MATERIALS AND METHODS Animals On 23 June 1990,50 bucks (mean 5 s.e.m., 19.8 2 0.69 kg) and 56 does (20.4 + 0.67 kg) (abbreviated LWl), and 82 bucks (40.8 5 0.73) (LW2) were selected from a group of feral goats captured on Nambi station (28' 122'E) in the Goldfields region of WA. Seven days later, another 58 bucks (19.0 2 0.68 S, kg) and 48 does (20.9 5 0.62 kg) (LWl), and 75 bucks (39.4 + 0.67 kg) (LW2) were selected from the same location. The goats were trucked 650 km to a feedlot at the Department of Agriculture Research Station, Katanning, WA (33' ' and 117'32' All animals were vaccinated against pulpy kidney and tetanus 43 s E). (Glanvac 3:l; Commonwealth Serum Laboratories, Australia) before the start of the experiment. The experiment was a factorial design. The effects of 2 periods of lot-feeding (14 cf. 7 days) on the proportions of LWl and LW2 goats that ate pellets and on their liveweight changes during lot-feeding and simulated shipping were examined. The lot-feeding phase was unreplicated, but, there were 2 replicates of each of the 4 treatments for the simulated voyage. The animals that died or lost more than 20% of their initial liveweight during simulated shipping were replaced with spare animals from the same treatment group. Lot-feeding The animals in each treatment were located in separate outdoor pens (1200 rnz area). The LWl and /hd. Both groups of goats were introduced to shipper pellets LW2 goats were stocked at 11 and 15 m' 194 Proc. Amt. Sot. Anim. Prod. 1994 Vol. 20 over a period of 3 days after being put in the pens, by increasing the amounts of pellets and decreasing the amounts of hay fed in equal increments (O:lOO%, 50:50% and lOO:O% for days 1, 2 and 3). The pellets had a dry matter (DM) content of 92.0%, a crude protein concentration of 135 g/kg, a modified acid detergent fibre (MADF) concentration of 261 g/kg and a DM digestibility of 60%. The hay was offered in racks and the pellets in troughs which provided 4.2 and 7.3 cm/head for the LWl and LW2 ooats. At the end of the introductory period, the LWl goats were given 700 g/hd.day and the LW2 goats 7200 g/hd.day of pellets. It was assumed that the pellets had an ME concentration of 9 MJ/kg and the quantities of pellets offered were calculated from the metabolisable energy requirements of goats growing at 50 g/day under range conditions (NRC 1981). Feed residues from each pen were collected daily and the animals subsequently offered fresh feed. Fresh water was available at all times. Simulated voyage Before simulation of live export the goats were trucked 70 km to simulate transport to a ship. The goats in each treatment and liveweight group were housed in separate pens (3.83 m x 3 m) for the 20 day simulated voyage. At the start of the voyage, the LWl goats were stocked at 48/pen which provided an area of 0.24 m2/goat. The stocking density for the LWl goats declined to 37/pen by day 8 and 35/pen by day 15. The /goat) throughout the period of the stocking density for the LW2 goats was maintained at 3l/pen (0.37 m' voyage. The LWl and LW2 goats were offered 700 and 1200 g/hd.day and the pellets were fed in troughs which provided 5.8 and 9.0 cm/head. Feed residues from each pen were collected daily and the animals subsequently offered fresh feed. Fresh water was available at all times. Measurements Dye was used to mark goats that ate the pelleted feed for a number of periods during lot-feeding and simulated shipping. Pellets were sprayed with a solution of Edicol Blue dye (35 g/L) (Bush Boake and Allen Limited, Australia) at a rate of 33 L/tonne. The goats were examined for dye around and inside the mouth and nose on days 1, 2, 6,7, 13 and 14 of lot-feedin g, and days 2,3, 15, 16 and 20 of the simulated voyage. Goats marked on either of the consecutive observation periods or on day 20 of the simulated voyage, were recorded as eating. Goats which lost in excess of 20% of their starting liveweight and were removed from the experiment were classified as non-feeders for analytical purposes. The liveweight of each animal was measured at the start of the experiment and every 7 days during lot-feeding and simulated shipping. Analytical methods A sample of the pellets was analysed for DM content by drying to a constant weight at 105�C for total nitrogen using a Kjeldahl procedure and for MADF by the method of Clancey and Wilson (1966). The DM digestibility was determined by the pepsin cellulase method (McLeod and Minson 1978). StatisticaZ analysis The differences in the proportions of non-feeders and the numbers of goats that failed to complete the simulated voyage for the treatment and liveweight groups were tested using log linear models. Analysis of variance was used to compare differences in liveweight change for treatment and liveweight groups. The treatment and liveweight group means were adjusted for the effect of the different proportions of male and female animals. RESULTS The mean daily DM intakes during lot-feeding (excluding the introductory period) were 307 and 451 g/goat.day for LWl goats in the 14-day and 7-day treatments and during simulated shipping were 598 and 554 g/goat.day. For LW2 goats in the 14-day and 7-day treatments, DM intakes during lot-feeding were 758 and 838 g/goat.day and during simulated shipping were 998 and 983 g/goat.day. The number of goats that died or lost more than 20% of their initial liveweight is shown in Table 1. There were no significant differences in the total proportions of goats that failed to complete the simulated voyage between treatment (28.8 cf. 20.7%) or liveweight groups (22.7 cf. 25.8%) when adjusted for the effect of sex. The percentages of goats that failed to eat pellets at the end of lot-feeding and during the simulated' voyage are shown in Table 2. The main effects are presented as there were no significant interactions. At the end of lot-feeding, there were nearly twice as many non-feeders among goats lot-fed for 7 days than those lot-fed for 14 days (24.6 cf. 13.1%, P < 0.05). There were still twice as many non-feeders in the 7-day treatment group on day 3 of simulated shipping (8.5 cf. 3.4%, P < 0.05) with more LWl goats 195 Proc. Amt. Sot. Anim. Prod. 1994 Vol. 20 Table 1. The number of goats in each of the 2 liveweight (LW) groups (LWl and LW2) that died (D) or were removed for reasons of liveweight loss (R) during the simulated voyage after being lot-fed for either 14 or 7 days failing to eat pellets than LW2 goats (8.0 cf. 1.8%, P < 0.05). However, there were no significant differences in the proportions of non-feeders between treatment and liveweight groups on days 16 and 20 of simulated shippin g, when goats that were removed for reasons of liveweight loss were included as nonfeeders. The percentages of the LWl goats that were non-feeders on day 20 of the simulated voyage were 2 and 0% for the 14-day and 7-day treatment groups, and 3% for both the LW2 treatment groups. A significantly higher proportion of the non-feeders than feeders at the end of lot-feeding subsequently died or were removed for reasons of liveweight loss during simulated shipping (52 cf. 19%. P c 0.001). Table 2. Percentage of goats (predicted means (s.e.m.) adjusted for the effect of sex) in each of the 2 liveweight (LW) groups (LWl and LW2) that failed to eat pellets at the end of lot-feeding and during the simulated voyage after being lot-fed for either 14 or 7 days The liveweight changes of the goats expressed in absolute terms (kg) or adjusted for metabolic body sizes (kg/kg LWo.75) over the period of lot-feedin g, simulated voyage and from the start of lot-feeding to the end of the simulated voyage, are presented in Table 3. Only the main effects are presented as there were no significant interactions. Over the period of lot-feeding, a Ooats lot-fed for 14 days suffered significantly greater liveweight losses than those lot-fed for 7 days (-2.2 cf. -0.08 kg, P c 0.001 and -0.18 cf. -0.01 kg/kg LW 0.75, P < 0.001). The LW2 goats suffered greater absolute liveweight losses than LWl goats (-1.6 cf. -0.65 kg, P c 0.01). Over the period of the simulated voyage, goats lot-fed for 7 days lost weight in comparison to those lot-fed for 14 days (-1.1 cf. 0.8 kg, P < 0.001 and -0.09 cf. 0.06 kg/kg LW'.75, P < 0.001) The LW2 goats lost liveweight in comparison to LWl goats (-0.90 cf. 0.59 kg, P < 0.001 and -0.09 cf.` 0.06 kg/kg LW 0.75, P < 0.001). From the start of lot-feeding to the end of simulated shipping, there was no difference in the absolute liveweight losses between goats lot-fed for either 7 or 14 days (-0.96 cf. -0.62 kg, P > 0.05). However, when adjusted for metabolic body size the goats lot-fed for 7 days lost significantly more weight (-0.08 cf. -0.05 kg/kg LW'.75, P c 0.05). Of the 2 liveweight groups only the LW2 goats lost weight over this period (-2.0 cf. 0.43 kg, P < 0.001 and -0.18 cf. 0.05 kg/kg LW'.75, P < 0.001). 196 Proc. Aust. Sot. Anim. Prod. 1994 Vol. 20 Table 3. The liveweight changes (least square means (s.e.m.) adjusted for the effect of sex) (kg or kg/kg LW'-75) during lot-feeding, simulated voyage and the start of lot-feeding to the end of simulated voyage for goats in each of the 2 liveweight (LW) groups (LWl and LW2) lot-fed for either 14 or 7 days DISCUSSION The findings of our study showed that during simulated shipping, goats lot-fed for 7 days lost weight in comparison to those lot-fed for 14 days. However, these losses in liveweight were negated by the liveweight losses that occurred during lot-feeding. Therefore, in the period from the start of lot-feeding to the end of simulated shippin g, the absolute liveweight losses recorded were similar (around 1 kg) although these were an underestimate of the true liveweight losses because of the removal of goats which lost more than 20% of their initial liveweight on days 7 and 14 of simulated shipping. Also the period of lot-feeding had no effect on either the proportion of non-feeders during simulated shipping or the proportion of goats that completed the simulated voyage. Consequently, increasing the period of lotfeeding from 7 to 14 days did not improve the performance of feral goats during live export. The evidence from our study su ggests that the failure of goats to eat in the feedlot may be a major reason for their poor performance aboard ship. A significantly higher proportion of the non-feeders at the end of lot-feeding died or were removed for reasons of liveweight loss during simulated shipping in comparison to feeders. The above parallels the findings of Norris et al. (1989) who showed that sheep which ate pellets in feedlots are more likely to continue to eat and survive aboard ship compared to those that failed to eat pellets in the feedlot. The results of this study su,, that there was no advantage in increasing the period of lot-feeding of OOest feral goats from 7 to 14 days. Further studies are needed to define the optimum period of lot-feeding from both an economic and welfare viewpoint in the light of the current regulations which require feral goats to be lot-fed for a period of at least 21 days before live export by ship (Australian Quarantine and Inspection Service 1992). ACKNOWLEDGMENTS We wish to thank Messrs R. Mills and A. Howe for their technical assistance and Mrs J. Speijers and Mr S. Daliwhal for their advice on the statistical analyses. REFERENCES AUSTRALIAN QUARANTINE and INSPECTION SERVICE (1992). Circular Memorandum CQAO(A) 168/92. CLANCEY, M.J. and WILSON, R.K. (1966). Proceedings of 10th International Grassland Congress, Helsinki, pp. 445-53. MCLEOD, M-N. and MINSON, D.J. (1978). Anim. Food Sci. Tech. 3: 277-87. NORRIS, R-T., RICHARDS, R.B. and DUNLOP, R.H. (1989). Aust. Vet. J. 66: 97-102. NATIONAL RESEARCH COUNCIL (1981). 'Nutrient Requirements of Goats' (National Academy Press: Washington DC). TOSELAND, B. (1990). Snippet the Cashmere Newsletter XI (2):15. 197