Balanced nutrition essential

Megalac is a rumen-protected fat supplement that increases energy supply in dairy cow diets without increasing the acid load. Photo by Daneka Hill

Balanced nutrient supply is essential for dairy cow productivity, according to Volac Wilmar Feed Ingredients global technical manager Richard Kirkland.

“Maintaining production, fertility and body condition score are key elements for a profitable dairy enterprise,” Dr Kirkland said.

“In nutritional terms, energy is the primary factor we must meet when formulating rations and this is a major challenge as milk production potential per cow increases, particularly through the early lactation period.”

Volac Wilmar Feed Ingredients is a joint venture between the global dairy business Volac and the massive Singapore-based agribusiness Wilmar, which processes oils, sugar, rice, flour and more.

Together the companies are offering a complete range of branded feed fat products — in particular, the popular Megalac feeds.

Dr Kirkland said the “balance of energy” in a cow’s diet needed to be considered carefully as it influenced all aspects of her performance.

“Cereals deliver that essential starch which promotes milk protein, but in excess risks rumen acidosis and low milk fat,” he said.

“In contrast, digestible fibre sources provide a source of acetate and butyrate for milk fat synthesis but deliver a lower energy density.”

Dr Kirkland said body condition was key to herd fertility.

“Delivering maximal megajoules of energy in early lactation is essential to support that genetic drive for producing milk and minimising the extent of body condition loss.”

Research data from the United Kingdom and United States have shown a link between reduced conception rates and extended days to first ovulation with body condition loss.

Dr Kirkland said as a general guide, conception rate decreased by 10 per cent per 0.8 unit decrease in body condition score through the early lactation period (Australian 8-point scale).

“This is a key area where rumen-protected feed fat supplements such as Megalac play a role, providing a highly concentrated source of ME MJ (around 2.5-times that of cereals) with a balance palmitic acid (C16:0) and oleic acid (C18:1) present in a 1.5:1 ratio.

“Palmitic acid increases ttNDFd, milk yield and milk fat yield while oleic acid improves the digestibility of total dietary fatty acids to supply an additional energy boost and improves the development of follicles, corpus lutea and eggs to help increase the likelihood of a successful pregnancy.”

Recent data from the US also demonstrates that oleic acid influences the insulin sensitivity status of body tissue in early lactation.

Insulin is an important hormone which drives energy to body fat stores and helps reduce body condition loss.

Dr Kirkland said energy supply was critical.

“Dairy cows need nutrients from a range of sources and the MJ of ME they supply will contribute to the overall energy balance of the cow, and the source of the ME supplied will determine the nature of the response achieved,” he said.

“Over-reliance on an individual energy source is likely to cause health, production and fertility issues, so diets need to be set up for success with a considered balance of nutrient sources.”