A report on the consumption, composition and nutritional adequacy of a mixture of lush green perennial ryegrass (Lolium perenne) and cocksfoot (Dactylis glomerata) fed ad libitum to Thoroughbred mares.

This study monitored the daily consumption and nutritional intake of non-pregnant Thoroughbred mares fed a mixture of perennial ryegrass and cocksfoot grass. The research outcomes showed that the amount of grass, and its nutritional content, ingested by the horses fell within their daily dietary requirements.

Study Design and Method

• The study comprised two trials each lasting for 24 hours. The subjects were non-pregnant Thoroughbred horses (mares) fed a mixture of two types of grasses – perennial ryegrass and cocksfoot grass – both freshly cut and green.
• In the first trial, two lactating mares with their foals and one mature non-lactating mare were observed. The mares’ body mass was calculated at the start of each trial.
• In the second trial, conducted three weeks later, the same lactating mares but a different non-lactating mare were observed. The mares were also given oat straw to eat freely along with the grass mixture.

Results of the Trials

• In the first trial, the lactating mares ate 75.5 kg and 61.0 kg of the grass mix while the non-lactating mare consumed 39.5 kg. The nutritional content of the mix included varying amounts of moisture, protein, calcium, phosphorus and dry matter.
• In the second trial, the lactating mares consumed 54.5 kg, and 56.0 kg while the non-lactating mare consumed 40.5 kg of the mix. The mix contained slightly different nutritional levels compared to the first trial. Both lactating mares consumed less grass compared to the first trial but all mares had access to oat straw which could be a contributing factor to this decrease.
• The foals did not consume the grass mix. The study did not mention the consumption of the diets by the foals which is crucial information.

Nutritional Adequacy of the Diets

• Researchers compared the total intake of protein, calcium, and phosphorus in the grass mix against the daily dietary requirements of the mares.
• The nutritional content of the grass mix seemed to fulfil the mares’ daily requirements. However, the exact comparison to dietary requirements was not specified in this abstract.

In conclusion, the study reports observations on the consumption patterns and nutritional intake of non-pregnant Thoroughbred mares fed ad libitum with a mixed grass diet. The indications suggest that this diet is adequate for these mares, in terms of nutritional value and quantity consumed, though a more detailed comparison with dietary needs and potential influence of supplementary feeding (oat straw included in the second trial) would enhance the findings’ validity.