@conference {40295,
	title = {Factors influencing the time to onset of oestrus after synchronisation treatment in ewes},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {51},
	year = {1991},
	month = {Jan},
	pages = {117-122},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {The effect of varying the height and bulk density of the leafy  zone of the sward on the ingestive behaviour of six 11 month old Red  deer hinds and seven 14 month old Romney ewe hoggets was examined. Deer  and sheep, confined to metabolism crates were randomly allocated 21  sward height x density combinations consisting of 7 heights (3-21 cm) x  3 bulk densities (0.19-0.75 mg DM/cm3). The Sorghum bicolor  swards were grown in 42 x 30 cm trays and had a deep, stem free leafy  zone. The required height of leaf was made accessible to animals by  raising or lowering each sward relative to a horizontal grid of fine  rods forming 3 cm x 3 cm squares below which animals could not graze.  The two lower bulk densities were engineered by snipping out alternate  rows, or rows and columns of plants. After grazing for at least 20  bites, bite depth, bite weight, grazed stratum bulk density, bite volume  and bite area were calculated.   The ingestive behaviour of deer and sheep was very similar in relation  to height and bulk density. The positive effect of height on bite depth  was on average 11 times as large as the negative effect of bulk density.  Height had little or no effect upon bite area, while bulk density had a  moderate, negative effect. On average a 100\% increase in height or bulk  density respectively resulted in a 64\% vs only 21\% increase in bite  weight; reflecting the fact that bite volume increased in relation to H  (39\%) but decreased in relation to bulk density (18\%). Thus height was  the major determinant of bite volume and bite weight via its influence  on bite depth.  },
	issn = {1176-5283},
	author = {Smith JF and Konlechner JA and Parr J}
}
