When applying precision nutrition to broiler diets it is crucial to consider how nutrients affect bird health and performance along with production budgets. Betaine has demonstrated its ability to support broilers facing heat-stress challenges and can also serve as an effective alternative to more expensive methyl-group donors like choline chloride.
Product Manager
Selko
The business of poultry production requires formulating diets that nurture flock performance as well as farm economics. Betaine provides a good example of a nutrient that supports broiler performance and profitable production. A trial conducted at the Trouw Nutrition Poultry Research Centre in Spain demonstrated the opportunity to replace up to 14% of a bird’s DL-methionine requirement with less expensive crystalized betaine while maintaining performance. As is often the case with precision nutrition, the trial inspired more questions and subsequent research.
Globally, heat-stress contributes to broiler production problems such as reduced growth. As the trial noted above was conducted under thermal-neutral conditions, researchers wanted to discover if betaine could deliver the same performance benefits for flocks experiencing heat-stress. Researchers also wanted to understand if betaine in the diet could be a more effective methyl donor than methionine to support heat-challenged flocks. Another trial conducted at the Trouw Nutrition Poultry Research center in summer 2023 sought to answer these questions.
BETAINE SUPPORTS BROILERS AND BUDGETS
More and more feed additives are being assigned a matrix value. The matrix value acknowledges that some feed additives interact with other nutrients, potentially creating a nutrient oversupply. Comprehending the matrix value of an ingredient within a precision feed formulation can reveal possibilities to prevent oversupplying costly ingredients while meeting an animal’s nutrient requirements with lower cost alternatives. This approach can enable the partial substitution of pricier ingredients in the diet, such as choline chloride and methionine. It is widely acknowledged that betaine can effectively supplant choline chloride in most poultry diets when matrix values are taken into consideration.
When applying precision nutrition to broiler diets it is crucial to consider how nutrients affect bird health and performance along with production budgets. Betaine has demonstrated its ability to support broilers facing heat-stress challenges and can also serve as an effective alternative to more expensive methyl-group donors like choline chloride. Traditionally utilized as a nutritional aid to mitigate the adverse effects of heat-stress, betaine is recognized for its favorable effect on methylation processes.
EFFECT OF HEAT STRESS ON METHYL NEEDS
Globally, flocks are often exposed to heat, which can lead to diminished growth. Heat stress increases the production of reactive oxygen species (ROS) and too much ROS results in oxidative stress. As methionine plays a role in managing antioxidants, an increase in ROS and oxidative stress will direct methionine in the diet to function as an antioxidant. An expected consequence of methionine acting in this manner is reduced growth as the nutrient’s work to facilitate protein deposition is impeded. Broilers have an increased need for methionine during heat-stress to address the lack of antioxidants and methyl donors necessary to maintain growth (Del Vesco et al., 2015). How significant this shortage of methionine is was tested by Zeits et al. (2020) as well. They showed that the extra need for methionine was not as big as expected. This dietary dilemma prompted researchers to conduct a trial evaluating whether it is better to supply extra methionine or betaine to flocks.
TRIAL DESIGN
A trial conducted at the Trouw Nutrition Poultry Research Centre, focused on two questions:
1) Is the matrix value observed under thermal-neutral conditions also valid under heat-stress conditions?
2) Which is better at reducing the negative effect of heat stress, DL-methionine or betaine?
Four dietary treatments were repeated under thermal-neutral (TN) and heat-stress (HS) conditions (Table 1). The control treatment (T1) received a diet containing methionine at the requirement level and no betaine. A second treatment group (T2) received diets that replaced 14% of the methionine requirement with 0.02% betaine (96% purity). Birds in treatment three (T3) received diets that included the control treatment + extra methionine and no betaine. Birds in treatment 4 (T4) received the T3 diet supplemented with 0.02% betaine (96% purity).
A total of 1,640 ROSS 308 male broilers were randomly assigned to the eight different treatments. Diets were corn, wheat, and soybean-meal-based. The minimum temperature in the heat-stress treatment was 25°C (77°F) and was increased to 32°C (89.6°F) during the day from day 11 to 28, and up to 29°C (84.2°F) from day 29 to 41.
BETAINE BENEFITS IN THERMAL-NEUTRAL AND HEAT-STRESS CONDITIONS
As expected, heat-stress had a significant effect on broiler performance, -10% BW and + 3% FCR (T1). Betaine also showed a significant effect, independent of the temperature. In both thermal-neutral and heat-stress conditions treatments containing betaine improved broiler performance significantly. Looking at the feed conversion ratio (FCR), a significant effect on temperature x betaine was found. This means that the positive effect of betaine during heat-stress conditions is significantly higher than betaine during thermal-neutral conditions, which were already significant. No significant effect was found on the combination of extra Met + betaine. Trial results show a numerical difference in favor of diets using the Met matrix value + betaine compared to the diets supplemented with extra methionine on top of the methionine requirement. In both thermal-neutral or heat-stress conditions, the combination of the Met matrix value and betaine saw no additional improvement when more Met was used. In these instances, addition of more Met raised diet cost without improving outcomes. This result helps demonstrate the validity of the established Met matrix value in thermal-neutral and heat-stress conditions.
In both thermal-neutral and heat-stress conditions, comparing the performance of birds in T1 and T2 reveals that birds that received 0.02% betaine outperformed birds receiving the treatment with Met levels at requirement and no betaine.
DETERMINING THE BETTER METHYL DONOR
The trial also investigated whether methionine or betaine was a better methyl donor. Researchers evaluated whether supplying extra methionine with or without betaine would further enhance growth performance.
A comparison of birds in T2 vs T3 and T4 showed that bodyweight (BW) and FCR were affected negatively when extra Met was added to the diet. The same effects were seen under thermal-neutral and heat-stress conditions. This trial confirmed that there is a significant betaine x temperature effect on FCR. A significant effect on BW and FCR was demonstrated with the addition of 0.02% betaine to birds’ diets.
The results showed that under both thermal-neutral and heat-stress conditions the best performing treatment applied the Met matrix value and added 0.02% betaine. Oversupplying methionine didn’t positively affect broilers’ BW and FCR.
CONCLUSIONS
Trial results confirm that the matrix value observed in the previous betaine study conducted under thermal-neutral conditions is also valid in heat-stress conditions. When evaluating the optimal methyl donor to support bird performance, the trial showed that betaine is a better methyl donor than methionine providing significant positive effects in both thermal-neutral and heat-stress conditions.
References
1. Del Vesco, A. P., Gasparino, E., Grieser, D. O., Zancanela, V., Voltolini, D. M., Khatlab, A. S., … & Neto, A. R. O. (2015). Effects of methionine supplementation on the expression of protein deposition-related genes in acute heat stress-exposed broilers. PLoS One, 10(2), e0115821.
2. Zeitz, J. O., Fleischmann, A., Ehbrecht, T., Most, E., Friedrichs, S., Whelan, R., … & Eder, K. (2020). Effects of supplementation of DL-methionine on tissue and plasma antioxidant status during heat-induced oxidative stress in broilers. Poultry science, 99(12), 6837-6847.
About Sanne van Beers
Sanne van Beers holds a Master’s degree in Animal Sciences from Wageningen University in The Netherlands. After which she joined Trouw Nutrition as swine gut health researcher. After 5 years in the research and development department of Trouw Nutrition she moved into a commercial role as product manager in Selko being responsible for technical support of Fibosel® and TNIBetain.
