Exogenous Polysaccharidases for Young Ruminants: A Review Interfacing Nutrition, Economics, and Health

Neonate ruminants possess little cell-wall and starch degrading enzyme activity. Importantly, early establishment of fibrolytic, amylolytic, and proteolytic capacities is influential for the early expansion of the reticulorumen epithelia. Such an early development in reticulorumen fermentation will enable a timely hepatic adaptation to volatile fatty acids assimilation. The early nutrient release in the reticulorumen can thus facilitate early weaning, reduce labor costs, save milk, and lessen health issues associated with late weaning. The principal objectives of this review are to delineate roles of exogenous, polysaccharidases (EP) in stimulating fermentation development of the reticulorumen in young ruminants, to discuss the literature on nutrient digestibility and calf performance response to dietary EPs, and to provide insights into future possibilities for using dietary EP for young ruminants. Evidence has been increasing that cow milk may reduce the risk of cancer development and cardiovascular diseases. Therefore, nutritional implications for humans of supplementing calf diets with EP and its potential for milk savings is also discussed. Dietary incentives leading to savings in milk would aid in meeting the rising human demands for well-distributed milk products. Applying EP to both pre- and post-weaning starters would need to be evaluated before EP could be commercially expected for young ruminants on a large scale. Any benefits of nutritional strategies to the animal industry must also consider their implications for human health. As such, dietary use of EP for young ruminants may be considered as an interface of animal nutrition, farm economics, and animal-human health.