
TY  - JOUR
A1  - Holroyd, RG 
A1  - Allan, PJ 
A1  - O'Rourke, PK 
T1  - Effect of pasture type and supplementary feeding on the reproductive performance of cattle in the dry tropics of north Queensland
JF  - Australian Journal of Experimental Agriculture
JO  - Aust. J. Exp. Agric.
Y1  - 1977
VL  - 17
IS  - 85
SP  - 197
EP  - 206
KW  - 
UR  - https://doi.org/10.1071/EA9770197 
N2  - A study was made over a four year period ( 1970-1 973) on the reproductive performance of cows grazing either native pasture stocked at 1 breeder 4.9 ha-1 or native pasture oversown with Townsville stylo (Stylosanthes humilis) and fertilized with superphosphate, stocked at 1 breeder 2.4 ha-1. Animals were supplemented on each pasture type with combinations of molasses, urea and phosphorus at various times of the year. Mating from September 1 to January 31 resulted in animals lactating during the dry season. At double the stocking rate, lactating cows on fertilized pastures had similar conception rates to those on native pasture. During a prolonged dry season, lactating cows on fertilized pasture had twice the conception rate and fewer required survival feeding. Urea compared with non-urea based supplements produced significant increases in conception rates of cows grazing native pasture especially during a dry year. Calves were born earlier, had shorter intercalving intervals and fewer cows had to be fed a survival ration when urea was available. On fertilized pasture, urea based supplements caused only a marginal increase in conception rate except in a dry year, when there was a significant increase. Over the four years, there was a diminishing response in the conception rate of lactating cows grazing native pasture and supplemented with phosphorus during the wet season compared with the control. On fertilized pasture, there was a variable but non-significant response. The addition of phosphorus either as a wet or dry season supplement to urea caused variable responses on each pasture type, but none differed significantly from that of urea. 
ER  -

