A comparison of the voluntary intake and digestion of a range of forages at different times of the year by the sheep and the red deer (Cervus elaphus)

Abstract

I. Comparisons were made between castrated male Scottish Blackface sheep and red deer (Cervus eluphus) of voluntary forage intake (VFI), digestibility and the mean retention time (MRT) of a particulatephase markel ('OSRu-phenanthro1ine) in the alimentary tract, when a range of forages: dried-grass pellets, chopped dried grass, fIesh-frozen Agrosris-Festucu spp. and heather (Cullunu vulgaris, L. Hull) were given at different times of the year.2. On both the dried-grass-pellet and chopped dried-grass diets the red deer and sheep ate similar quantities. Both species had a higher VFI of dried-grass pellets in July than in November. The sheep digested the dried-grass-pellet diet better than the red deer and this was associated with a longer MRT of the particulate-phase marker in the alimentary tract.3. The VFI of Agrosfis-Festuca spp. and heather by the red deer was twice that of the sheep. The VFI of heather by the sheep increased by 32 % between January and April, and the VFI of both the AgrostisFestuco spp. and heather diets by the red deer increased by 65-70 %. The sheep digested the Agrostis-Fesfucu spp. better than the red deer but the red deer digested the heather slightly better than the sheep. MRT of the particulate-phase marker was greater for the sheep than for the red deer on both diets.The digestibility and MRT of both diets in the red deer did not decrease with the seasonal increase in VFI, suggesting a possible hypertrophy of the alimentary tract.Domesticated sheep and feral red deer (Cervus elaphus) are the principal producers of food for human consumption from a large proportion of the rough grazings of Scotland.In any study of land use or resource management it is necessary to know whether there are differences between the two species in the biological efficiency with which they use the resource. These can be brought about by differences between the species in their grazing behaviour, ability to consume more of a diet and digest it better, in their efficiency of utilization of the end-products of digestion and in their nutrient requirements. It is the second aspect which is examined in this paper. Sheep and red deer eat many similar plant species which range from highly digestible grasses in summer to poorly digested grasses and heather (Calluna vulgaris, L. Hull) in winter (Hobson, 1969), but seasonal fluctuations in voluntary intake by red deer (Simpson, 1976) and other Cervidae (Long, Cowan, Strawn, Wetzel & Miller, 1966;McEwan & Whitehead, 1970) would appear to be greater than those found with sheep (Gordon, 1964). Preliminary results of Kay & Goodall (1976) have indicated that with good-quality roughage diets there were only small differences between sheep and red deer in voluntary intake (VFI), digestibility and mean retention time of undigested residues in the gut. However, comparisons using poor quality roughages have not been made.The present experiments were designed to examine the differences between the sheep and the red deer in VFI, digestibility and mean retention time of a particulate...

Role of early experience in the development of preference for low-quality food in sheep

“…Ingestion of a high-fiber food (i.e. mature oat hay) during the exposure period may have increased reticulo-rumen capacity in EL (Milne et al, 1978;Distel and Provenza, 1991), which may have contributed to their increased acceptance of LQF.…”

Effects of subcutaneous melatonin implants during long daylength on voluntary feed intake, rumen capacity and heart rate of red deer (Cervus elaphus) fed on a forage diet

“…Rumen capacity has been proposed to limit VFI of ruminants consuming forage diets (Black, 1990), and it has been suggested that red deer may be able to increase rumen capacity during summer thus accommodating their seasonal increase in VFI (Milne et al 1978;Milne, 1980). However, results of the present study showed that rumen capacity remained relatively constant, and that one mechanism used by red deer to increase VFI was to increase rumen pool size as a proportion of total capacity.…”

“…, 1985). High VFT is associated with increasing daylength (spring-summer) and low VFI is associated with decreasing daylength (autumn-winter;Milne et al 1978; Suttie ef al. 1984;Domingue, 1989).…”

“…The fistulated animals were kept in metabolism crates (Milne et al 1978;Domingue, 1989) and the non-fistulated animals were kept in individual concrete pens with sawdust provided as bedding.…”

Managing livestock using animal behavior: mixed-species stocking and flerds

“…Although one usually considers mixed-species stocking to refer to two or more of the predominant domestic ruminant livestock species (Ralphs et al, 1986;Abaye et al, 1994;del Pozo et al, 1998;Animut et al, 2005a and2005b;Celaya et al, 2007;Sanon et al, 2007), wildlife if present should be considered as part of the mix (Grelen and Thomas, 1957;Milne et al, 1978;Bryant et al, 1979;Campbell and Johnson, 1983;Bastian et al, 1991;Gallina, 1993;Didier et al, 1994;Kreuter andWorkman, 1996 andVavra, 2005;Williams and Haynes, 2006;Anderson and McCuistion, 2008). Although not specifically addressed in this paper, the addition of wildlife to the species mix can create additional management challenges and economic opportunities from both ecotourism (Georgiadis et al, 2007) and sport hunting or game cropping (Denney, 1972;Demarais et al, 1990).…”