An assessment of intraruminal chromium controlled release capsules for measuring feed intake in dairy cows : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science in Animal Science at Massey University

Abstract

Indonesia is a tropical country that has an east-west length of 5000 km from 92 to 141 east longitude and a width of 1500 km from 6 to 11 south latitude (Indonesia Official Year Bood 1989). Approximately 60% of total employment is related to the agricultural sector and 70% of non-oil exoirts are attributable to agriculture (The Fourth Five Year Development Plan 1984). The livestock industry is closely integrated with crop production, particularly in Java and Bali. In other areas, livestock plays a significant role in family life as draft power, particularly in the transmigration areas. In East Indonesia (East Nusatenggara and South Sulawesi) conventional grazing systems are of greater importance. The 1987 Indonesian livestock population comprised approximately 7 million draft cattle, 0.3 million dairy cattle, 10 million goats, 5 million sheep, 2 million bullaloes and 211 million poultry. As the fifthe largest populated country in the world in 1990 (180) million Indonesian people consumed 2.24, 4.18, 5.34 kg of egg, milk and meat per capita per annum. This is projected to increase by 1993 to 2.52, 4.54 and 6.79 kg/person of egg, milk and meat respectively, but this will still remain the lowest consumption of animal protein among South East Asia countries. To meet the projected increase in consumption of animal products the population and production of Indonesian livestock will need to be increased to meet the needs of a population which is growing at the rate of 2.60% per annum. (The Fourth Five Year Development Plan 1984). Initial studies with CRC indicate that they could have considerable potential for improving current knowledge of feed intake at pasture. CRC increase labour efficiency for measuring feed intake compared to twice-daily administration of Cr(2)0(3) in the form of either gelatin capsules or impregnated paper. They would be particularly suited to the extensive grazing situation such as in Indonesia where it is not practical to handle cattle each day to administer faecal markers. The purpose of this investigation was therefore to validate cattle CRC for indirectly estimating faecal output and hence feed intake in dairy cows fed indoors. A secondary objective was to compare pasture intake outdoors estimated indirectly from Cr dilution in the faecal sample and by the pasture cuts technique.