Pros And Cons Of Growth Promoters

Discuss the growth promoters that are used in production animals with a particular focus on their mechanisms of action and the pros and cons related to their usage.

The use of growth promoters has reached an all time high, in the livestock industry, in the past few years owing to the ever increasing human population and their requirements for more protein. Many growth promoters allow for improved feed efficiency, decreased time to reach optimal carcass weight, and improved health under intensified conditions. Antibiotics are one of the most common growth promoters available, however, new alternatives are being considered. Currently, growth promoters are administered as feed additives or hormonal implants.

Antibiotics are used prophylactically

They promote live lean weight gain by repartitioning nutrients inside the body (5), decreasing fat content whilst increasing the muscle mass. They are safe for human consumption, allow for less feed, water, land and fuel usage with the same weight gain. However, there is a high incidence of death seen in cattle given beta agonists (7), and there is a current study with regards to their negative effects on joints (6). They are also known to affect the behaviour of animals negatively. There is a need for better alternatives to the abovementioned and further options will be discussed

Lactobacillus spp., Bifidobacterium spp.) are beneficial intestinal bacteria added to animal feed. They prevent harmful organisms from colonizing the GIT and improve feed utilization (Maré, 2009). In cattle, they help to create an anaerobic environment, competing with lactic acid producing bacteria and increasing nutrient absorption (due to an increased volatile fatty acid production) (1). Competition with pathogens for colonization sites and nutrient sources is another advantage (1).Prebiotics (e.g. oligofructose, fructooligosaccharides, inulin) are nutrients that promote the growth of beneficial microorganisms in the GIT and are indigestible to the animal (Maré, 2009). Ruminants are able to degrade most prebiotics which means that residues in the meat are not likely (Maré, 2009). Unfortunately, these growth promoters are very expensive and need to be administered in large doses in order to show their