Influence of High Levels of Plant and Animal Fats in Calf Starters on Growth, Feed Consumption, and Palatability

In a growth experiment with seven calves per starter, the addition of 10% brown grease, 10% hydrogenated cottonseed oil, or 5% of each to calf starters markedly reduced consumption and weight gain.The addition of 10% of each of the fats further reduced weight gains and starter consumption.The simple and partial correlations between starter consumption and weight gains were 0.84 and 0.85, which indicates that a major portion of the reduction in growth was associated with reduced starter intake.In a cafeteria study, each of nine calves significantly preferred the control starter.However, one calf demonstrated a similar decisive preference for the starter with 10% added brown grease.In another cafeteria study with 11 calves, 1% brown grease did not significantly affect palatability of a calf starter.The addition of certain fats to feeds has increased the energy intake and growth rates of poultry.When calculated on a dry matter basis it has been shown that calves can utilize high levels of certain fats in milk and milk replacers.For example, Hopper et al. (6) used skimmilk containing 4% butyrated lard on a liquid basis--equivalent to about 30% on a dry basis--and obtained a very high growth rate.Numerous studies have been conducted in which many types of fats and oils have been fed in milk replacers.Animal fats such as tallow and lard have proven satisfactory [Wiese et al. (12), Gullickson et al. (5), and Hopper et al. (6)].However, Wiese et al. (12) demonstrated that, whereas calves grew well on a certain milk replacer when fed in liquid form, they would not eat the same material dry.Other studies have shown that hydrogenation improved the results obtained with certain oils when utilized in milk replacers [Jarvis et al. (8) and Jacobson et al. (7) ].Experiments at Connecticut [Johnson et al. (9)] indicated that calves fed dry starters containing inedible tallow consumed greater amounts of estimated net energy, resulting in a 5-6% increase in growth.Levels of tallow up to 10% were studied, but neither the optimum nor the maximum safe level was determined.None of their differences was statistically significant.The main purpose of this study was to determine the effect of high levels of certain animal and vegetable fats in calf starters on growth, feed consumption, and palatability of the starters.Brown grease was used, as it is a low-cost source of animal fat, frequently used by the feed industry.Hydrogenated cottonseed oil was used because this type of fat has given better results in milk