August 22, 2019

Interpretive Summary: Phytogenic feed additives for dairy cattle

Interpretive Summary: Productive and physiological responses of lactating dairy cows supplemented with phytogenic feed ingredients

By Dr. Emily Taylor

The objective of this study was to enhance the productivity and welfare of dairy cattle by using a blend of phytogenic ingredients as a feed additive. These phytogenic ingredients include condensed tannins which decrease the degradation of protein in the rumen, cinnamaldehyde which enhances rumen fermentation and alleviates systemic inflammation in cattle receiving high-concentrate diets, and compounds isolated from pungent plants that appear to have immune benefits and increase the synthesis of digestive enzymes in monogastrics. Milk production, composition, and physiological responses were measured when these phytogenic ingredients were added to the diets of thirty-six lactating Holstein X Gir cows.

As hypothesized, an increase in milk yield was observed in cows being supplemented with the phytogenic blend. Because the increase was not seen until 14 days following the initiation of treatments, it is suggested that a two week adaption period is needed. A gain in BCS was observed in supplemented cows; however, the overall changes were not enough to cause differences. Cows from both treatments were given injections of rBST with blood samples collected for glucose and IGF-1 analysis. While glucose concentration was similar between treatments, IGF-1 increased within supplemented cows. The collective increase in milk production, change in BCS, and increase of IGF-I indicate an improved nutritional status for the supplemented cows. Milk composition, however, was not affected by the addition of the phytogenic blend.  

Moreover, the addition of the phytogenic blend did not alleviate the incidence of mastitis. Serum haptoglobin concentrations, which increase when the ruminal ecosystem is disrupted, were reduced, most likely due to the optimization of rumen function and fermentation. Stressors may also have a response on haptoglobin concentrations with cortisol mediating the response. Reduced serum haptoglobin and cortisol concentrations have also increased the nutritional status of the cows in addition to having a positive effect on milk production.

In conclusion, it appears that the use of phytogenic ingredients as a feed additive may be a valid strategy to improve milk production in dairy cattle.

To view the full article, visit Translational Animal Science.