@conference {40247,
	title = {Comparison of growth and carcass traits of ram lambs of three breeds from a flock screened for prolificacy and a Romney control flock},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {50},
	year = {1990},
	month = {Jan},
	pages = {397-402},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {This paper reviews the application of intraruminal chromium   controlled release capsules (CRC, Captec (NZ) Ltd, Auckland) to the   measurement of herbage intake in ruminants. The capsules are designed   to provide for the linear release of Cr2O3 over c. 25 days in sheep and   c. 20 days in cattle. Uniform release of Cr2O3 is achieved 2 to 3 days   after oral administration of the CRC but steady state levels of Cr2O3 in   the faeces are usually not achieved until day 7 or 8 in sheep and day 5   or 6 in cattle. Where cross-over or multiple feeding level experimental   designs are applied, time should be allowed for Cr2O3 to adjust to a new   steady state in the faeces before sampling for each new treatment. The   period of time required varies from 3 to more than 5 days depending on   the size of feed intake change. The continuous mode of marker release   in the rumen reduces diurnal variation of Cr2O3 in the faeces and this   allows rectal sampling regimens to be applied at different times of each   sampling day. Sward sampling of faeces reduced disturbance of animal   grazing to a minimal level since Cr2O3 is delivered by a single CRC   application. The effects of level of feed intake and feed type on the   rate of Cr2O3 release are usually small, but release rates may be up to   13\% lower in rumen-fistulated than in non-fistulated animals and may   differ for capsules of the same time applied to different ruminant   species. Reduced animal handling, flexible faecal sampling times and   lower labour requirements with CRC technology, compared to daily   drenching of Cr2O3, enable the number of experimental animals to be   increased. This improves the likelihood of detecting differences in   mean intake between groups. Intakes of individual animals will not be   reliably estimated with chromic oxide CRC until the digestibility of   herbage consumed by individual animals can be measured more accurately.    },
	issn = {1176-5283},
	author = {McEwan JC and Davis GH and Dodds KG and Fennessy PF and Clarke JN and Hishon M}
}
