@conference {40294,
	title = {The efficacy of used CIDR devices for synchronisation of oestrus and post-mating treatment},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {51},
	year = {1991},
	month = {Jan},
	pages = {111-116},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {An upper limit to the force animals exert to server a bite maybe  important in maintaining grazing momentum. Structural strength of  accessible pasture components would then determine bite dimensions and  weight.   Pure perennial ryegrass turfs (surface area 0.1m2 x 0.1m soil depth),  were manipulated by clipping to produce 3 pasture heights (5, 10 and  15cm) x 3 sward structures (varying in leaf to pseudostem ratio and bulk  density). Six sheep grazed 4 turfs fixed to a force plate of each  height and bulk density. Mean peak bite force, bite weight, bite depth,  bite area, bite volume and grazed stratum bulk density were calculated.   Peak bite force increased with sward surface height but significantly so  only between 10 and 15 cm. Sward structure had no effect except on the  5cm sward treatment with the highest grazed stratum bulk density. Bite  depth and bite weight increased with pasture height and were not  influenced by sward structure at a constant height. Bite area was  similar at all sward heights, but decreased as grazed stratum bulk  density increased. On short swards, proximity to the ground restricted  bite depth and bite weight rather than peak bite force. Low bite  weights per newton bite force may constrain bite depth and weight rather  than absolute peak bite force.  },
	issn = {1176-5283},
	author = {Smith JF and Konlechner JA and Parr J}
}
@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}
}
