The quantification of the effect of increasing levels of various fats on body weight gain, efficiency of food conversion and food intake of growing chicks

A study, based on data from the literature, was carried out to establish the quantitative effect of increasing levels of various fats on food intake, weight gain and efficiency of food conversion of growing chicks.

The fats concerned were soyabean oil, soyabean soapstock, maize oil, lard, grease and tallow. Their effect was studied by using regression analyses.

It was found that the addition of fat, both animal fats and vegetable oils, diminishes food intake. The food intake decreases significantly with rising percentages of fat according to a linear function. No differences in effect between various fats could be demonstrated.

The incorporation of various fats improves the weight gain, although the increase was not related to the amount of fat added. The improvement in weight gain differs from one fat to an other.

The addition of fats improves efficiency of food conversion, but varies according to the kind of fat. Here the improvement is correlated with the level of fat added.

The difference in improvement of food conversion can be only partially explained by differences in absorbability and metabolisable energy of the fats.

It is concluded that certain fats ameliorate the efficiency of food conversion and, in some cases, weight gain to a higher degree as may be expected from their metabolisable energy content. It might be possible that some fats possess one or more factors which improve the efficiency of metabolisable energy or exert a protein anabolic action.