Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-19T09:46:02.521Z Has data issue: false hasContentIssue false
  • English
  • Français

Photoperiodic entrainment of seasonal changes in the appetite, feeding behaviour, growth rate and pelage of pony colts

Published online by Cambridge University Press:  18 August 2016

Z. Fuller ,
J. E. Cox  and
C.McG. Argo
Z. Fuller
Affiliation:
School of Biological and Earth Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK
J. E. Cox
Affiliation:
Department of Veterinary Clinical Sciences and Animal Husbandry, University of Liverpool, Leahurst, Chester High Road, Neston CH64 7TE, UK
C.McG. Argo*
Affiliation:
School of Biological and Earth Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK
*
‡Corresponding author.
Get access

Abstract

Relationships among photoperiod and changes in voluntary food intake, feeding behaviour, growth and pelage were determined in seven, 2-year-old pony colts (182·4 (s.e. 5·4) kg). Individually housed colts were provided with ad libitum access to a complete pelleted diet (gross energy = 16·7 MJ/kg dry matter). Voluntary food intake (VFI, kg/ day) was calculated daily and body weights were recorded weekly throughout the 36-week study. Feeding behaviour was evaluated at approximately 4-week intervals by continuous observation (24 h), and the hair weight density (HWD, mg/cm2) of shoulder pelage was determined fortnightly. Day length was artificially manipulated to mimic the prevailing mid-summer photoperiod (16 h light: 8 h dark, 16L: 8D). After 1 week of the study (and the preceding fortnight), day length was abruptly decreased and thereafter animals were exposed to alternating 14-week periods of short (SD, 8L: 16D) and long days (LD, 16L: 8D). The mean daily VFI of individual ponies was calculated weekly and normalized for digestible energy (DE) content and metabolic body weight (DEI, MJ/kg M0·75). The average daily gain (ADG, kg/day) in body weight of each individual was calculated weekly. The apparent digestibility of dietary energy (digestibility) was determined over 72 h (no. = 6) on two occasions (days 92 to 95 and 190 to 193) during the study. Digestibility was similar in both periods (0·48, s.e. 0·01). DEI, ADG and HWD changed in a cyclic manner throughout the study. The period of the appetite cycle (24·4 (s.e. 1·3) weeks) did not differ from that of the 28-week photoperiodic regime. DEI decreased from a maximum of 1·4 (s.e. 0·03) MJ/kg M0.75 per day (day 21), to a nadir of 0·75 (s.e. 0·02) MJ/kg M0.75 per day (day 154, P < 0·001) and had increased (P < 0·001) to attain a second zenith (0·93 (s.e. 0·01) MJ/kg M0.75 per day) before the end of the study. Ponies ate discrete meals of similar duration, but meal frequency was associated with changes in VFI (r = 0·77) as was proportion of time spent feeding (r = 0·79). Changes in ADG reflected those of DEI. Body weight was stable for 4 weeks at the nadir of the appetite cycle. Maximal HWD was coincident with the nadir of the appetite and growth cycles. Regression of individual values for DEI on ADG described a linear relationship (R2 = 0·80) which could be used to predict the energy requirements of growing ponies maintained under similar conditions:

DEI total (MJ/kg M0·75 per day) = 0·654ADG (kg/day) + 0·789 (1).

The duration of the photoperiod, appetite, growth and pelage cycles were similar, suggesting a causal relationship. Physiological responses to photoperiodic change were not immediate and exhibited a delay of 5 to 8 weeks.

Keywords

appetitecoltsgrowthmetabolic rateseasonal variation
Type
Non-ruminant nutrition, behaviour and production
Information
Animal Science , Volume 72 , Issue 1 , February 2001 , pp. 65 - 74
Copyright
Copyright © British Society of Animal Science 2001

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Argo, C. M., Cox, J. E. and Gray, J. L. 1991. Effect of oral melatonin treatment on the seasonal physiology of pony stallions. Journal of Reproduction and Fertility, Supplement 44: 115–125.Google ScholarPubMed
Argo, C.McG., Smith, J. S. and Kay, R. N. B. 1999. Seasonal changes of metabolism and appetite in Soay rams. Animal Science 69: 191–202.Google Scholar
Barth, K. M., Williams, J. W. and Brown, D. G. 1977. Digestible energy requirements of working and nonworking ponies. Journal of Animal Science 44: 585–589.Google Scholar
Blaxter, K. L. 1962. The energy metabolism of ruminants. Hutchison Scientific and Technical, London.Google Scholar
Blaxter, K. L. and Boyne, A. W. 1982. Fasting and maintenance metabolism of sheep. Journal of Agricultural Science, Cambridge 99: 611–620.CrossRefGoogle Scholar
Cymbaluk, N. F. 1990. Cold housing effects on growth and nutrient demand of young horses. Journal of Animal Science 68: 3152–3162.CrossRefGoogle ScholarPubMed
Cymbaluk, N. F. and Christison, G. I. 1989a. Effects of diet and climate on growing horses. Journal of Animal Science 67: 48–59.CrossRefGoogle ScholarPubMed
Cymbaluk, N. F. and Christison, G. I. 1989b. Effects of dietary energy and phosphorous content on blood chemistry and development of growing horses. Journal of Animal Science 67: 951–958.CrossRefGoogle ScholarPubMed
Dawson, W. M., Phillips, R. S. and Speelman, S. R. 1945. Growth of horses under Western range conditions. Journal of Animal Science 4: 47–54.CrossRefGoogle Scholar
Ellis, R. N. W. and Lawrence, T. L. J. 1978. Energy under-nutrition in the weanling filly foal. I. Effects on subsequent live-weight gains and onset of oestrus. British Veterinary Journal 134: 205–211.CrossRefGoogle ScholarPubMed
Frape, D. 1986. Equine nutrition and feeding. Longman Scientific and Technical, Harlow.Google Scholar
Gallagher, J. R. and McMeniman, N. P. 1988. The nutritional status of pregnant and non-pregnant mares grazing South East Queensland pastures. Equine Veterinary Journal 20: 414–416.Google Scholar
Goss, R. J. 1969. Photoperiodic control of antler cycles in deer. I. Phase shift and frequency changes. Journal of Experimental Zoology 170: 311–324.CrossRefGoogle Scholar
Henneke, D. R., Potter, G. D. and Kreider, J. L. 1983. Relationship between condition score, physical measurements and body fat percentages in mares. Equine Veterinary Journal 15: 371–372.Google Scholar
Iason, G. R., Sim, D. A., Foreman, E., Fenn, P. and Elston, D. A. 1994. Seasonal variation of voluntary food intake and metabolic rate in three contrasting breeds of sheep. Animal Production 58: 381–387.Google Scholar
Jelan, Z. A., Jeffcott, L. B., Lundeheim, N. and Osborne, M. 1996. Growth rates in thoroughbred foals. Pferdeheilkunde 12: 291–295.CrossRefGoogle Scholar
Kirk, R. E. 1982. Experimental design: procedures for the behavioural sciences, second edition. Brooks/Cole Publishing Co., New York.Google Scholar
Kleiber, M. 1932. Body size and metabolism. Hilgardia 6: 315–353.Google Scholar
Kooistra, L. H. and Ginther, O. J. 1975. Effect of photoperiod on reproductive activity and hair in mares. American Journal of Veterinary Research 36: 1413–1419.Google Scholar
Moen, A. N. 1978. Seasonal changes in heart rates, activity, metabolism and forage intake of white-tailed deer. Journal of Wildlife Management 42: 715–738.CrossRefGoogle Scholar
Mossberg, I. and Jönnson, H. 1996. The influence of day length and temperature on food intake and growth rate of bulls given concentrate or grass silage ad libitum in two housing systems. Animal Science 62: 233–240.Google Scholar
Nilssen, K. J. and Ringberg, T. 1980. Seasonal changes in body weight, food intake and thyroxine in free ranging and captive Svalbard reindeer, Rangifer tarandus platyrhynchus. Proceedings of the second international reindeer/caribou symposium, Roros, Norway, pp. 329–332.Google Scholar
Ozoga, J. J. and Verme, L. J. 1970. Winter feeding patterns of penned white-tailed deer. Journal of Wildlife Management 34: 431–439.Google Scholar
Pagan, J. D. and Hintz, H. F. 1986. Equine energetics. I. Relationship between body weight and energy requirements in horses. Journal of Animal Science 63: 815–821.Google Scholar
Pagan, J. D., Jackson, S. G. and Caddel, S. 1996. A summary of growth rates in thoroughbreds in Kentucky. Pferdeheilkunde 12: 285–289.CrossRefGoogle Scholar
Sibbald, A. M. and Rhind, S. M. 1997. The effect of previous body condition on appetite and associated insulin profiles in sheep. Animal Science 64: 247–252.CrossRefGoogle Scholar
Stricklin, W. R., Wilson, L. L. and Graves, H. B. 1976. Feeding behaviour of Angus and Charalais-Angus cows during summer and winter. Journal of Animal Science 43: 721–732.CrossRefGoogle Scholar
Walkden-Brown, S.W, Norton, B. W. and Restall, B. J. 1994. Seasonal variation in voluntary feed intake and growth in Cashmere bucks fed ad libitum diets of low or high quality. Australian Journal of Agricultural Research 45: 355–366.Google Scholar