Calf

 

Over the next several weeks we will be releasing a series of articles entitled “How the ingredients of a ruminant’s diet can help save the world”. The series was written by VetSalus Director Alasdair Moffett who is currently studying Ruminant Nutrition, a distance learning course at Aberystwyth University. A full list of references will be published at the conclusion of the series.

 

What is a ruminant’s diet?

Fifty million years ago, ruminants were omnivores before they evolved into obligate herbivores. At present there are 6 families of ruminants, encompassing nearly 200 species. They are defined as members of the Artiodactyla mammalian order, suborder Ruminantia, which possess a rumen, reticulum, omasum (or an organ homologous to an omasum) and an abomasum, which regurgitate and masticate undigested foods whilst at rest, but do not possess upper incisors. The definition derives from the latin etymology, ‘ruminare’ which translates as ‘to chew again’. The wonder of the ruminant is their ability to convert photosynthetic energy derived plant material, which is inedible to humans, into nutrient dense, highly digestible meat and milk. Both possess high-quality protein and energy, with red meat containing all the essential amino acids for human health and nature’s most complete food – milk, provides a plethora of essential micronutrients in a readily available format, especially calcium, magnesium, potassium, zinc, and phosphorus.

Within the anaerobic and methanogenic rumen plant material eg. cellulose and hemi-cellulose is degraded and digested by the highly populated and diverse microbiota of bacteria, protozoa, fungi, archaea present into both microbial protein and volatile fatty acids. The latter provides around 70% of the ruminants’ daily energy requirements, with the ratio of acetate, butyrate and propionate dependent on the type of diet being fed. Further to this carbohydrate source, there is need for amino acids, essential fatty acids eg. linoleic and linolenic acids, vitamins; particularly the fat soluble A, D and E, and numerous minerals including copper, as well as water. Ruminants are regarded as not having an essential amino acid requirement due to their de-novo synthesis ability, however in bovines, methionine and lysine are regarded as production limiting amino acids. A ruminant’s dietary requirements will be dependent upon whether it is for maintenance, maximum daily live weight gain or for maximising milk yield.

Part 2 of the article series will be available next week; keep an eye on our social media channels, Twitter and LinkedIn, to ensure you don’t miss the release.