Betaine Improves Milk Yield in Grazing Dairy Cows Supplemented with Concentrates at High Temperatures

Abstract

Betaine is an organic osmolyte sourced from sugar beet that accumulates in plant cells undergoing osmotic stress. Since the accumulation of betaine lowers the energy requirements of animals and, therefore, metabolic heat production, the aim of this experiment was to investigate if betaine supplementation improved milk yield in grazing dairy cows in summer. One hundred and eighteen Friesian × Holstein cows were paired on days in milk and, within each pair, randomly allocated to a containing treatment of either 0 or 2 g/kg natural betaine in their concentrate ration for approximately 3 weeks during February/March 2015 (summer in Australia). The mean maximum February temperature was 30 °C. Cows were allocated approximately 14 kg dry matter pasture and 7.5 kg of concentrate pellets (fed in the milking shed) per cow per day and were milked through an automatic milking system three times per day. Betaine supplementation increased average daily milk yield by over 6% (22.0 vs. 23.4 kg/day, p < 0.001) with the response increasing as the study progressed as indicated by the interaction (p < 0.001) between betaine and day. Milk fat % (p = 0.87), milk protein % (p = 0.90), and milk somatic cell count (p = 0.81) were unchanged by dietary betaine. However, betaine supplementation increased milk protein yield (677 vs. 719 g/day, p < 0.001) and fat yield (874 vs. 922 g/day, p < 0.001) with responses again being more pronounced as the study progressed. In conclusion, dietary betaine supplementation increased milk and component yield during summer in grazing dairy cows.

Betaine Supplementation Improves the Production Performance, Rumen Fermentation, and Antioxidant Profile of Dairy Cows in Heat Stress

“…VFA, acetate, and propionate concentrations increased with the supplementation of betaine in the present study, so it is possible that betaine supplementation could increase rumen fermentation by serving as a source of either ruminally available nitrogen or methyl groups [26]. The results of the present study are in line with previous research by Dunshea et al [1]. Wdowiak-Wróbel et al [27] reported that betaine supplementation has an osmoprotective effect, and it promotes the growth of favorable microbiota in rumen under environmental stress conditions.…”

“…Curvilinear dose responses to betaine supplementation have also been noticed in beef cattle and sheep during HS with improvements at 2 and 15 g betaine per day, respectively [6,10]. The reason for the moderation in response to high doses of Bet during HS may be that the stimulation of hepatic metabolism and a resultant upsurge in heat production by the liver may offset the decrease in heat production due to the osmoprotective effects of betaine in the rest of the body [1].…”

“…Dairy cows reach optimum production performance in temperatures from 5 to 25 • C. In high environmental temperature and humidity, dairy cows cannot dissipate body heat to prevent a rise in body temperature [1,2]. Generally, dairy cow production performance is affected by a diminished feed intake when the temperature-humidity index (THI) exceeds 72 [3].…”

“…For example, betaine (Bet) is an osmolyte [7] and a methyl donor [8]. It performs as a molecular chaperone [1], reduces the vulnerability of microbes to stress [9], and under some conditions, has antimicrobial activity [1]. In addition, Bet is an amino acid and has the ability to improve the production performance of different animals [1], such as steers [10] and pigs [11].…”

“…It performs as a molecular chaperone [1], reduces the vulnerability of microbes to stress [9], and under some conditions, has antimicrobial activity [1]. In addition, Bet is an amino acid and has the ability to improve the production performance of different animals [1], such as steers [10] and pigs [11]. These results suggest that betaine has the potential to reduce heat stress by reducing energy expenditure [6], thereby reducing metabolic heat production and maintaining osmotic balance in animals facing heat stress.…”