Animal Bioscience

Asian Australasian Association of Animal Production Societies (아세아태평양축산학회)
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Relationships between dietary rumen-protected lysine and methionine with the lactational performance of dairy cows - A meta-analysis

  • Agung Irawan (Vocational School, Universitas Sebelas Maret) ;
  • Ahmad Sofyan (Animal Feed and Nutrition Modelling (AFENUE) Research Group, Faculty of Animal Science, IPB University) ;
  • Teguh Wahyono (Animal Feed and Nutrition Modelling (AFENUE) Research Group, Faculty of Animal Science, IPB University) ;
  • Muhammad Ainsyar Harahap (Research Center for Animal Husbandry, National Research and Innovation Agency (BRIN)) ;
  • Andi Febrisiantosa (Research Center for Food Technology and Processing, National Research and Innovation Agency (BRIN)) ;
  • Awistaros Angger Sakti (Research Center for Animal Husbandry, National Research and Innovation Agency (BRIN)) ;
  • Hendra Herdian (Animal Feed and Nutrition Modelling (AFENUE) Research Group, Faculty of Animal Science, IPB University) ;
  • Anuraga Jayanegara (Animal Feed and Nutrition Modelling (AFENUE) Research Group, Faculty of Animal Science, IPB University)
  • Received : 2023.03.13
  • Accepted : 2023.07.13
  • Published : 2023.11.01
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Abstract

Objective: Our objective was to examine the relationships of supplemental rumen-protected lysine (RPL) or lysine + methionine (RPLM) on lactational performance, plasma amino acids (AA) concentration, and nitrogen use efficiency of lactating dairy cows by using a meta-analysis approach. Methods: A total of 56 articles comprising 77 experiments with either RPL or RPLM supplementation were selected and analyzed using a mixed model methodology by considering the treatments and other potential covariates as fixed effects and different experiments as random effects. Results: In early lactating cows, milk yield was linearly increased by RPL (β1 = 0.013; p<0.001) and RPLM (β1 = 0.014; p<0.028) but 3.5% fat-corrected milk (FCM) and energy-corrected milk (ECM) (kg/d) was increased by only RPL. RPL and RPLM did not affect dry matter intake (DMI) but positively increased (p<0.05) dairy efficiency (Milk yield/DMI and ECM/DMI). As a percentage, milk fat, protein, and lactose were unchanged by RPL or RPLM but the yield of all components was increased (p<0.05) by feeding RPL while only milk protein was increased by feeding RPLM. Plasma Lys concentration was linearly increased (p<0.05) with increasing supplemental RPL while plasma Met increased (p<0.05) by RPLM supplementation. The increase in plasma Lys had a strong linear relationship (R2 = 0.693 in the RPL dataset and R2 = 0.769 in the RPLM dataset) on milk protein synthesis (g/d) during early lactation. Nitrogen metabolism parameters were not affected by feeding RPL or RPLM, either top-dress or when supplemented to deficient diets. Lactation performance did not differ between AA-deficient or AA-adequate diets in response to RPL or RPLM supplementation. Conclusion: RPL or RPLM showed a positive linear relationship on the lactational performance of dairy cows whereas greater improvement effects were observed during early lactation. Supplementing RPL or RPLM is recommended on deficient-AA diet but not on adequate-AA diet.

Keywords

Acknowledgement

The authors would like to address acknowledgement to Research and Innovation for Indonesia Maju (RIIM) of the National Research and Innovation Agency (BRIN) of 2022-2023 fiscal year (DFRI-BRIN No. 65/II.7/HK/2022) for supporting this study.

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