The approach to antibiotic use in animal husbandry requires specific considerations, particularly in relation to the type of animal bred with specific reference to the age and resistance of the animals. In the beef cattle rearing sector, the greater resistance and robustness of the animals, together with the application of good management practices, make it possible to avoid preventive antibiotic treatments and decidedly limit their overall use.
The “receiving phase” is, however, the one phase of the rearing cycle recognised as being particularly critical due to the high health risk associated with it. For animals naturally accustomed to living together in herds and therefore with social relations founded on a well-established and stable hierarchy, factors such as a change of environment, feed and, above all, mixing with other animals, may subject them to severe stress.
Stress is known to cause an impairment of their immune defences, which, together with reduced feed consumption and rumination, results in an increased risk of both digestive and respiratory problems, such as BRD (Bovine Respiratory Disease). The use of functional feed additives could limit the consequences of stress, guaranteeing prompt and effective immune reactivity and rapidly restabilising conditions of normal rumination. It is in this setting that yeast pro- and post-biotics play a central role.
With the aim of defining a effective nutritional approach to support the reduction in the use of antimicrobials under conditions of high stress, an assessment was made. The effect of a combination of yeast probiotic, organic selenium and yeast parietal fractions rich in mannans and beta 1,3-1,6 glucans on productive performance, health and digestive efficiency of newly arrived beef cattle was studied.
The lower incidence and severity of health problems together with the enhanced digestive activity and both ruminal and intestinal stability led to an improvement of the average daily weight gain in the treatment group (Figure 1). This significant improvement was found to be equivalent to 93 g/head/day during the adaptation phase. The increase in ADG was 31 g/head/day when taking the entire rearing period into account. This result is confirmed in the literature, which reveals that the reduced growth that takes place during the days immediately following arrival due to disease or nutritional adaptation difficulties, is not recovered during the subsequent phases of the rearing cycle, thus representing a net loss. In fact, prompt recovery of the full physiological immune and digestive function is a key factor, not only for the animals’ welfare but also for their growth and productive efficiency.
It therefore emerges that dedicating time and money to the critical phases of any production process represents an indispensable condition, which becomes obligatory when the health of animals and safety of consumers are at stake. Efforts and investments are however normally repaid by the fact that the increasingly restrictive commercial requirements are met, guaranteeing a strong position on the market and larger shares of it for the farm, and that the difference between the costs and benefits is normally in favour of the latter. The production cost, which may seem to be higher, is actually lower due to the reduction in health costs and the improvement of growth and feed efficiency (Table 1). The case at hand is a clear example of this as, for an overall investment of about 5.17 euros per head, the economic return is about 18.66 euros per head.
In conclusion, the results of the study show how the use of a pro- and post biotic supplementation with proven efficacy is a practice to be adopted regularly during the critical phase of adaptation of imported beef cattle. It improves the immune function and resistance of the animals to pathogens resulting in the reduced administration of antibiotics and an increased awareness of their use.
Cario Angelo Sgoifo Rossi, University of Milan, Vespa Dept
Silvia Grossi University of Milan, Vespa Department,
Francesca Martinelli, Doctor of Animal Science,
Riccardo Compiani University of Milan ,
Valentin Nenov Global Ruminants Manager, Phileo by Lesaffre