Abstract:
Proc. Aust. Soc. Anim. Prod. (1978) 12: 284 THE EFFECT OF SALINE BORE WATER ON THE GROWTH OF WEANER CATTLE G.R. SAUL* and P.C. FLINN* In western Victoria, the ingestion of underground water containing high levels of magnesium (Mg) salts has been associated with growth and health problems in young or lactating cattle. A report by the VIRASC (1969) recommends the upper limits for Total Soluble Salts (TSS) and Mg for young or lactating cattle to be 6000 ppm and 250 ppm respectively, with corresponding limits of 10000 ppm and 400 ppm for mature beef cattle. Many bores contain satisfactory levels of TSS but between 250 and 600 ppm Mg. Two experiments were conducted at the Pastoral Research Institute during 1975-76 to study the effect of high magnesium water on young weaner cattle. In experiment 1, 36 weaner cattle were allocated to two equal groups according to sex, breed and weight. One group drank bore water containing 3900 ppm TSS and 370 ppm Mg and the control group drank water containing 70 ppm TSS and 1 ppm Mg. In experiment 2, 20 weaner heifers were similarly allocated except that the bore water contained 4500 ppm TSS and 500 ppm Mg. Both experiments were carried out in feedlots. Experiment 1 ran for 138 days and Experiment 2 for 60 days. All groups were fed pasture hay ad Zibitwn which contained 9.24% Mg. The measurements and results are shown in Table 1. The two types of bore water studied in these experiments did not cause scouring. or reduce growth rates. The extra Mg ingested was voided in the faeces. These observations suggest that the current recommendations for Mg are too conservative for weaner cattle. VIC. IRRIGATION RES. ADVISORY SERVICES COMMITTEE (1969). 'Quality aspects of Farm Water Supplies'. * Pastoral Research Institute, P.O. Box 180, Hamilton, Vic. 3300. 284.