The Farmers Mart Oct-Nov 2018 - Issue 59

CATTLE 37 • OCT/NOV 2018 Why gut health is essential if you want to improve the yield of your cattle When it comes to dairy cattle, the key for farmers is to help cows to utilise carbohydrates and fatty acids for milk production. There are a number of reasons why the bodies of dairy cows may not be using these essential nutrients for milk production. These range from conditions such as leaky gut to heat stress - according to the latest research. What role does the gut play in nutrient absorption and milk production? Gut health plays an important role in the absorption of nutri- ents. A gut microbiome is the vast quantities of bacteria and fungal microorganisms that live in a par- ticular environment. Unlike other animals, ruminants, like cows, have several distinct gut micro- biomes. Crucial to animal health, these microbiomes help break down food, assist with nutrient absorption and fight infection. In cattle, the rumen acts as the ‘first stomach’ and, along with the reticulum, begins the digestion of complex plant matter into smaller particles which can be absorbed. Plant matter is chewed, partially digested in the rumen, and sent back to the mouth as cud for the animal to chew further. Eventually, contractions in the rumen moves the plant matter into the reticulum where it is ‘filtered’ to allow only small particles through. Studies have found a strong cor- relation between a high volume of healthy bacteria in the rumen and milk production yields. These healthy bacteria only develop in a cow’s rumen following weaning, as plant matter requires much more complex digestion than milk. Next, the omasum absorbs the majority of the water from the plant matter along with nutri- ents like potassium and sodium, further filtering out large particles before it enters the abomasum. The abomasum is primarily responsible for digesting proteins and plant-based cellulose, which are almost impossible for other animals to break down. The final stages of digestion take place in the small and large intes- tine, which break the nutrients down using enzymes so that they can be absorbed into the blood. The large intestine, in particular, is where 10-15% of a cow’s energy is produced through fermentation, but an excess of fermentable car- bohydrates in the large intestine can lead to digestive problems. Fermentation increases the acidity of the intestine which can reduce the absorption of other nutrients while also damaging the intestinal wall. What role does the gut play in illness? Damage to the intestinal wall can lead to leaky gut syndrome (LGS), where undigested food particles, toxic waste products and bacteria ‘leak’ across the intestinal barrier and into the blood, causing disease and other illnesses. There is mounting evidence to suggest that LGS is caused partly by high-concentrate feed. The high starch contained in these feeds leads to higher concen- trations of carbohydrates being passed into the intestine. Once in the intestine, the starch ferments causing “hindgut” gut acidosis which, in turn, can lead to LGS. What’s more, up to 70% of the immune response happens in the gut, so cows need a good Dr Rosemary Warring supply of nutrients to help fight off illness. An immune response causes nutrients and energy to be used primarily for processes other than milk production, limiting a cow’s yield and leading to higher production costs for farmers. So, not only does a healthy gut lead to greater nutrient absorp- tion and higher milk yields, it minimises the chance of infection or illness which leads to lower yields. How can calving cows be helped to return to full productivity? Part of the problem for farmers lies in the stress of calving on a cow’s body. Calving, with the need to produce milk for her off- spring, places great demands on the animal’s body. To help meet these physical demands, farmers often provide high-concentrate feed. But as we’ve seen, this can lead to LGS. Cows suffering from LGS are likely to reduce their feed intake, further exacerbating the issue. The solution may lie in feeds that are high in easily digesti- ble carbohydrates and contain the enzyme amylase, which is responsible for breaking down starch and carbohydrates into digestible sugars. Recent studies by Tharos have shown that a high-carb, easily digestible, malt extract enriched with amylase can increase nutrient absorption in the gut of horses. Although they have very different gastrointestinal systems, combining simple carbs with am- ylase is thought to have a similar effect on cattle. Further research is needed, and it is possible that this could provide a solution for farmers, supporting recently calved cows get back to full strength and milk production. What’s interesting is that the malt extract seems to appeal to other fussy eaters in the ani- mal kingdom, including horses and cats. This could potentially provide a solution to help cows that have gone off their feed. For cattle experiencing LGS, this could be the key to breaking the vicious cycle of not eating and help the animals return to robust good health. Dr Rosemary Waring http://tharos.co.uk/

The Farmers Mart Oct-Nov 2018 - Issue 59 | Page 37