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Shearing at the end of summer affects body temperature of free-living Angora goats (Capra aegagrus) more than does shearing at the end of winter

Published online by Cambridge University Press:  01 July 2009

R. S. Hetem ,
B. A. de Witt ,
L. G. Fick ,
A. Fuller ,
G. I. H. Kerley ,
S. K. Maloney ,
L. C. R. Meyer  and
D. Mitchell
R. S. Hetem*
Affiliation:
Brain Function Research Group, School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa
B. A. de Witt
Affiliation:
Brain Function Research Group, School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa
L. G. Fick
Affiliation:
Brain Function Research Group, School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa
A. Fuller
Affiliation:
Brain Function Research Group, School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa
G. I. H. Kerley
Affiliation:
Department of Zoology, Centre for African Conservation Ecology, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa
S. K. Maloney
Affiliation:
Brain Function Research Group, School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa Physiology, School of Biomedical, Biomolecular, and Chemical Science, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
L. C. R. Meyer
Affiliation:
Brain Function Research Group, School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa
D. Mitchell
Affiliation:
Brain Function Research Group, School of Physiology, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, South Africa
*
E-mail: robyn.hetem@wits.ac.za
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Abstract

Angora goats are known to be vulnerable to cold stress, especially after shearing, but their thermoregulatory responses to shearing have not been measured. We recorded activity, and abdominal and subcutaneous temperatures, for 10 days pre-shearing and post-shearing, in 10 Angora goats inhabiting the succulent thicket of the Eastern Cape, South Africa, in both March (late summer) and September (late winter). Within each season, environmental conditions were similar pre-shearing and post-shearing, but September was an average 5°C colder than March. Shearing resulted in a decreased mean (P < 0.0001), minimum (P < 0.0001) and maximum daily abdominal temperature (P < 0.0001). Paradoxically, the decrease in daily mean (P = 0.03) and maximum (P = 0.01) abdominal temperatures, from pre-shearing to post-shearing, was greater in March than in September. Daily amplitude of body temperature rhythm (P < 0.0001) and the maximum rate of abdominal temperature rise (P < 0.0001) increased from pre-shearing to post-shearing, resulting in an earlier diurnal peak in abdominal temperature (P = 0.001) post-shearing. These changes in amplitude, rate of abdominal temperature rise and time of diurnal peak in abdominal temperature suggest that the goats’ thermoregulatory system was more labile after shearing. Mean daily subcutaneous temperatures also decreased post-shearing (P < 0.0001), despite our index goat selecting more stable microclimates after shearing in March (P = 0.03). Following shearing, there was an increased difference between abdominal and subcutaneous temperatures (P < 0.0001) at night, suggesting that the goats used peripheral vasoconstriction to limit heat loss. In addition to these temperature changes, mean daily activity increased nearly two-fold after March shearing, but not September shearing. This increased activity after March shearing was likely the result of an increased foraging time, food intake and metabolic rate, as suggested by the increased water influx (P = 0.0008). Thus, Angora goats entered a heat conservation mode after shearing in both March and September. That the transition from the fleeced to the shorn state had greater thermoregulatory consequences in March than in September may provide a mechanistic explanation for Angora goats’ vulnerability to cold in summer.

Keywords

Angora goatsbody temperatureshearingfleece
Type
Full Paper
Information
animal , Volume 3 , Issue 7 , July 2009 , pp. 1025 - 1036
Copyright
Copyright © The Animal Consortium 2009

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References

Alexander, G, Lynch, JJ, Mottershead, BE 1979. Use of shelter and selection of lambing sites by shorn and unshorn ewes in paddocks with closely or widely spaced shelters. Applied Animal Ethology 5, 51–69.CrossRefGoogle Scholar
Appleman, RD, Delouche, JC 1958. Behavioral, physiological and biochemical responses of goats to temperature, 0°C to 40°C. Journal of Animal Science 17, 326–335.CrossRefGoogle Scholar
Askins, GD, Turner, EE 1972. A behavioral study of Angora goats on west Texas range (Un estudio sobre ias actividades de cabras de Angora en un pastizal natural en el oeste de Texas). Journal of Range Management 25, 82–87.CrossRefGoogle Scholar
Avondo, M, Bordonaro, S, Marletta, D, Guastella, AM, D’Urso, G 2000. Effects of shearing and supplemental level on intake of dry ewes grazing on barley stubble. Small Ruminant Research 38, 237–241.CrossRefGoogle ScholarPubMed
Baker, MA, Doris, PA 1982. Effect of dehydration on hypothalamic control of evaporation in the cat. Journal of Physiology 322, 457–468.CrossRefGoogle ScholarPubMed
Beatty, DT, Barnes, A, Fleming, PA, Taylor, E, Maloney, SK 2008. The effect of fleece on core and rumen temperature in sheep. Journal of Thermal Biology 33, 437–443.CrossRefGoogle Scholar
Bennett, JW 1972. The maximum metabolic response of sheep to cold: effects of rectal temperature, shearing, feed consumption, body posture, and body weight. Australian Journal of Agricultural Research 23, 1045–1058.CrossRefGoogle Scholar
Bianca, W, Kunz, P 1978. Physiological reactions of three breeds of goats to cold, heat and high altitude. Livestock Production Science 5, 57–69.CrossRefGoogle Scholar
Birrell, HA 1989. The influence of pasture and animal factors on the consumption of pasture by grazing sheep. Australian Journal of Agricultural Research 40, 1261–1275.Google Scholar
Boko, M, Niang, I, Nyong, A, Vogel, C, Githeko, A, Medany, M, Osman-Elasha, B, Tabo, R, Yanda, P 2007. Climate change 2007: impacts, adaptation and vulnerability. In Contribution of working Group II to the fourth assessment report of the Intergovernmental Panel on Climate Change (ed. ML Parry, OF Canziani, JP Palutikof, PJ van der Linden and CE Hanson), pp. 433–467. Cambridge University Press, Cambridge, UK.Google Scholar
Burton, I, Lim, B 2005. Achieving adequate adaptation in agriculture. Climatic Change 70, 191–200.CrossRefGoogle Scholar
Cena, K, Monteith, JL 1975. Transfer processes in animal coats. I. Radiative transfer. Proceedings of the Royal Society of London. Series B-Biological Sciences 188, 377–393.Google Scholar
Cronje, PB 1995. Differences in glucose response to insulin stimulation and fasting between Angora goats of two different phenotypes. Small Ruminant Research 16, 121–127.CrossRefGoogle Scholar
Done-Currie, JR, Wodzicka-Tomaszewska, M, Lynch, JJ 1984. The effects of thermoregulatory behaviour on the heat loss from shorn sheep as measured by a model ewe for micro-climate integration. Applied Animal Behaviour Science 13, 59–70.CrossRefGoogle Scholar
Donnelly, JB, Lynch, JJ, Webster, ME 1974. Climatic adaptation in recently shorn Merino sheep. International Journal of Biometeorology 18, 233–247.CrossRefGoogle ScholarPubMed
Dýrmundsson, OR 1991. Shearing time of sheep with special reference to conditions in northern Europe: a review. Iceland Agricultural Science 5, 39–46.Google Scholar
Fourie, TJ 1984. A comparative study of the effects of cold exposure on the heat production of Angora (Capra aegagrus) and Boer (Capra hircus) goats (‘n Vergelykende studie van die effek van koue bloodstelling op die hitteproduksie van angora- (Capra aegagrus) en boerbokke (Capra hircus)). MSc, University of Port Elizabeth.Google Scholar
Fuller, A, Meyer, LCR, Mitchell, D, Maloney, SK 2007. Dehydration increases the magnitude of selective brain cooling independently of core temperature in sheep. American Journal of Physiology-Regulatory Integrative and Comparative Physiology 293, R438–R446.CrossRefGoogle ScholarPubMed
Fusch, C 2000. Measurement of water turnover using deuterium dilution: impact of periodically varying turnover rates on precision and accuracy. Clinical Chemistry of Laboratory Medicine 38, 961–964.CrossRefGoogle ScholarPubMed
Glass, MH, Jacob, RH 1992. Losses of sheep following adverse weather after shearing. Australian Veterinary Journal 69, 142–143.CrossRefGoogle ScholarPubMed
Hargreaves, AL, Hutson, GD 1990. Some effects of repeated handling on stress responses in sheep. Applied Animal Behaviour Science 26, 253–265.CrossRefGoogle Scholar
Hetem, RS, Maloney, SK, Fuller, A, Meyer, LCR, Mitchell, D 2007. Validation of a biotelemetric technique, using ambulatory miniature black globe thermometers, to quantify thermoregulatory behaviour in ungulates. Journal of Experimental Zoology A: Comparative and Experimental Biology 307, 342–356.CrossRefGoogle ScholarPubMed
Hofman, WF, Riegle, GD 1977. Thermorespiratory responses of shorn and unshorn sheep to mild heat stress. Respiration Physiology 30, 327–338.CrossRefGoogle ScholarPubMed
Hofmeyr, HS, Joubert, DM, Badenhorst, FJG, van De Steyn, GJ 1965. Adaptability of sheep and goats to a South African tropical environment. Proceedings of the South African Society of Animal Production 4, 191–195.Google Scholar
Hofmeyr, HS, Guidry, AJ, Waltz, FA 1969. Effects of temperature and wool length on surface and respiratory evaporative losses of sheep. Journal of Applied Physiology 26, 517–523.CrossRefGoogle ScholarPubMed
Holmes, CW, Clark, DA 1989. Effects of cold conditions on the oxygen consumption of shorn goats. Proceedings of the New Zealand Society of Animal Production 49, 175–177.Google Scholar
Holmes, CW, Moore, YF 1981. Metabolisable energy required by feral goats for maintenance and the effects of cold climatic conditions on their heat production. Proceedings of the New Zealand Society of Animal Production 41, 163–166.Google Scholar
Hopkins, PS, Knights, GI, Feuvre, ASL 1978. Studies of the environmental physiology of tropical Merinos. Australian Journal of Agricultural Research 29, 161–171.CrossRefGoogle Scholar
Hutchinson, JCD 1968. Deaths of sheep after shearing. Australian Journal of Experimental Agriculture and Animal Husbandry 8, 393–400.CrossRefGoogle Scholar
Hutchinson, JCD, Bennett, JW 1962. Effect of cold on sheep. Wool Technology and Sheep Breeding 9, 11–16.Google Scholar
Hutchinson, KJ, McRae, BH 1969. Some factors associated with the behaviour and survival of newly shorn sheep. Australian Journal of Agricultural Research 20, 513–521.CrossRefGoogle Scholar
Jessen, C, Dmi’el, R, Choshniak, I, Ezra, D, Kuhnen, G 1998. Effects of dehydration and rehydration on body temperatures in the black Bedouin goat. Pflügers Archiv: European Journal of Physiology 436, 659–666.CrossRefGoogle ScholarPubMed
Johnson, KG 1971. Body temperature lability in sheep and goats during short-term exposure to heat and cold. Journal of Agricultural Science 77, 267–272.CrossRefGoogle Scholar
Lachica, M, Aguilera, JF 2003. Estimation of energy needs in the free-ranging goat with particular reference to the assessment of its energy expenditure by the 13C-bicarbonate method. Small Ruminant Research 49, 303–318.CrossRefGoogle Scholar
MacFarlane, WV, Morris, RJH, Howard, B 1958. Heat and water in tropical Merino sheep. Australian Journal of Agricultural Research 9, 217–288.CrossRefGoogle Scholar
MacFarlane, WV, Howard, B, Morris, RJH 1966. Water metabolism of Merino sheep shorn during summer. Australian Journal of Agricultural Research 17, 219–225.CrossRefGoogle Scholar
McArthur, AJ, Monteith, JL 1980. Air movement and heat loss from sheep. I. Boundary layer insulation of a model sheep, with and without fleece. Proceedings of the Royal Society of London. Series B-Biological Sciences 209, 187–208.Google Scholar
McGregor, BA 1985. Heat-stress in Angora wether goats. Australian Veterinary Journal 62, 349–350.CrossRefGoogle ScholarPubMed
McGregor, BA 1986. Water-intake of grazing Angora wether goats and Merino wether sheep. Australian Journal of Experimental Agriculture 26, 639–642.CrossRefGoogle Scholar
McGregor, BA 1998. Nutrition, management and other environmental influences on the quality and production of mohair and cashmere: a review with particular reference to Mediterranean and annual temperate climatic zones. Small Ruminant Research 28, 199–215.CrossRefGoogle Scholar
McGregor, BA 2001. Avoiding weather induced deaths of goats. In Australian goat notes (ed. AJ Simmonds), pp. 76–77. Australian Cashmere Growers Association, Kellyville, NSW, Australia.Google Scholar
McGregor, BA, Butler, KL 2008a. The effect of frequency and timing of shearing on the growth of fibre and objective and subjective attributes of Angora goat fleeces. Journal of Agricultural Science 146, 351–361.CrossRefGoogle Scholar
McGregor, BA, Butler, KL 2008b. Relationship of body condition score, live weight, stocking rate and grazing system to the mortality of Angora goats from hypothermia and their use in the assessment of welfare risks. Australian Veterinary Journal 86, 12–17.CrossRefGoogle Scholar
Milne, TA 2008. The effects of thicket transformation on the diet and body condition of Angora Goats. MSc, Nelson Mandela Metropolitan University.Google Scholar
Morris, RJH, Howard, B, MacFarlane, WV 1962. Interaction of nutrition and air temperature with water metabolism of merino wethers shorn in winter. Australian Journal of Agricultural Research 13, 320–334.CrossRefGoogle Scholar
Mottershead, BE, Alexander, G, Lynch, JJ 1982. Sheltering behaviour of shorn and unshorn sheep in mixed or separate flocks. Applied Animal Ethology 8, 127–136.CrossRefGoogle Scholar
Nijland, MJ, Baker, MA 1992. Effects of hydration state on exercise thermoregulation in goats. American Journal of Physiology. Regulatory Integrative and Comparative Physiology 263, R201–R205.CrossRefGoogle ScholarPubMed
Panaretto, BA 1967. Some factors affecting off-shear losses in sheep. Wool Technology and Sheep Breeding 14, 27–31.Google Scholar
Panaretto, BA, Vickery, MR 1971. Cardiovascular parameters in shorn sheep prior to and during their exposure to a cold, wet environment. Quarterly Journal of Experimental Physiology, Cognitive Medical Science 56, 101–107.CrossRefGoogle ScholarPubMed
Parer, JT 1963. The effects of wool length and nutrition on heat reactions of Merino sheep in the field. Australian Journal of Experimental Agriculture 3, 243–248.CrossRefGoogle Scholar
Pennisi, P, Costa, A, Biondi, L, Avondo, M, Piccione, G 2004. Influence of the fleece on thermal homeostasis and on body condition in Comisana ewe lambs. Animal Research 53, 13–19.CrossRefGoogle Scholar
Phillips, GD, Raghavan, GV 1970. Responses of unshorn and shorn sheep to thermal stress. Journal of Physiology 208, 317–328.CrossRefGoogle ScholarPubMed
Piccione, G, Caola, G 2003. Influence of shearing on the circadian rhythm of body temperature in the sheep. Journal of Veterinary Medicine Series A-Physiology Pathology Clinical Medicine 50, 235–240.CrossRefGoogle ScholarPubMed
Piccione, G, Caola, G, Refinetti, R 2002. Effect of shearing on the core body temperature of three breeds of Mediterranean sheep. Small Ruminant Research 46, 211–215.CrossRefGoogle Scholar
Piccione, G, Giannetto, C, Casella, S, Caola, G 2008. Seasonal change of daily motor activity rhythms in Capra hircus. Canadian Journal of Animal Sciences 88, 351–355.CrossRefGoogle Scholar
Robertshaw, D 1968. The pattern and control of sweating in the sheep and the goat. Journal of Physiology 198, 531–539.CrossRefGoogle ScholarPubMed
Scholes, RJ, Midgley, GF, Wand, SJE 1999. The vulnerability and adaptation of rangelands. South African Climate Change Country Studies Contract Report, Division of Water, Environment and Forest Technology, CSIR, Pretoria, pp. 1–19.Google Scholar
Shelton, M 1993. The problem of cold stress or “off-shear” losses. In Angora goat and mohair production, pp. 176–191. Anchor Publishing Company, San Angelo, TX, USA.Google Scholar
Slee, J 1966. Variation in the responses of shorn sheep to cold exposure. Animal Production 8, 425–434.Google Scholar
Slee, J 1972. Habituation and acclimatization of sheep to cold following exposures of varying length and severity. Journal of Physiology 227, 51–70.CrossRefGoogle ScholarPubMed
Stuart-Hill, G, Aucamp, A 1993. Carrying capacity of the succulent valley bushveld of the Eastern Cape. African Journal of Range and Forage Science 10, 1–10.CrossRefGoogle Scholar
Sykes, AR, Slee, J 1969a. Cold exposure of Southdown and Welsh Mountain sheep. 1. Effects of breed, plane of nutrition and acclimatization to cold upon resistance to body cooling. Animal Production 11, 65–75.Google Scholar
Sykes, AR, Slee, J 1969b. Cold exposure of Southdown and Welsh Mountain sheep. 2. Effects of breed, plane of nutrition and previous acclimatization to cold upon skin temperature, heart rate, shivering and respiratory rate. Animal Production 11, 77–89.Google Scholar
Symonds, ME, Bryant, MJ, Lomax, MA 1986. The effect of shearing on the energy metabolism of the pregnant ewe. British Journal of Nutrition 56, 635–643.CrossRefGoogle ScholarPubMed
Vlok, J, Euston-Brown, D, Cowling, R 2003. Acocks’ Valley Bushveld 50 years on: new perspectives on the delimitation, characterisation and origin of thicket vegetation. South African Journal of Botany 69, 27–51.CrossRefGoogle Scholar
Webster, MED, Lynch, JJ 1966. Some physiological and behavioural consequences of shearing. Proceedings of the Australian Society of Animal Production 6, 234–239.Google Scholar
Wentzel, D, Viljoen, KS, Botha, LJJ 1979. Physiological and endocrinological reactions to cold stress in the Angora goat. Agroanimalia 11, 19–22.Google Scholar
Wheeler, JL, Reardon, TF, Lambourne, LJ 1962. The effect of pasture availability and shearing stress on herbage intake of grazing sheep. Australian Journal of Agricultural Research 14, 364–372.CrossRefGoogle Scholar
Young, BA 1981. Cold stress as it affects animal production. Journal of Animal Science 52, 154–163.CrossRefGoogle ScholarPubMed