Performance, Body Composition, and Behavior of Lambs Consuming Different Extruded Roughage to Concentrate Ratios
Abstract
High levels of roughage in the diet reduce energy density and limit voluntary intake due to ruminal physical constraints. In this context, extrusion processing can improve digestibility and enable greater fiber inclusion in the diet, thereby improving animal performance. The objective of this study was to evaluate the productive performance, body composition, and ingestive behavior of lambs that were fed different proportions of extruded roughage to concentrate (R:C). Twenty lambs, weighing 25.0 ± 2.8 kg and aged 120 ± 8 d, were distributed in a completely randomized design and fed one of four proportions of roughage to concentrate: 30:70; 40:60; 50:50; or 60:40. Lambs were housed in collective pens throughout the experimental period. Body weight (BW) and body condition score (BCS), body conformation (in vivo biometric measurements), average daily gain (ADG, g/d), and in vivo carcass characteristics were not influenced by the treatments (p>0.05). An increase in roughage levels linearly increased total chewing time (TCT) (p<0.05). In contrast, idle time (IT) decreased linearly (p<0.05). There was a quadratic and positive linear effect of evaluation day (p<0.05) for BW, BCS, in vivo biometric measurements, ADG during the periods between 15–30 d (p=0.03) and 75–90 d (p<0.05), and in vivo carcass characteristics (p<0.05). There was an interaction between R:C ratio and the day of assessment for loin eye area, with day 84 superior to day 0 (p<0.05). The inclusion of higher levels of roughage in fully extruded diets increases TCT and decreases IT without affecting productive performance or body composition in sheep.
Full text article
References
Abadi, M. H., Ghoorchi, T., Amirteymouri, E., & Poorghasemi, M. (2023). The effect of different processing methods of linseed on growth performance, nutrient digestibility, blood parameters and ruminate behaviour of lambs. Veterinary Medicine and Science, 9(4), 1771-1780. https://doi.org/10.1002/vms3.1149
Amirteymoori, E., Khezri, A., Dayani, O., Mohammadabadi, M., Khorasani, S., Mousaie, A., & Kazemi-Bonchenari, M. (2021). Effects of linseed processing method (ground versus extruded) and dietary crude protein content on performance, digestibility, ruminal fermentation pattern, and rumen protozoa population in growing lambs. Italian Journal of Animal Science, 20(1), 1506-1517. https://doi.org/10.1080/1828051X.2021.1984324
Assis, T. S., Schultz, E. B., Oliveira, K. A., Siqueira, M. T. S., Sousa, L. F., & Macedo-Júnior, G. L. (2022). Evaluation of extruded roughage with different additives in sheep diet. Acta Scientiarum Animal Sciences, 44(1), e53447. https://doi.org/10.4025/actascianimsci.v44i1.53447
Bell, A. W., Bauman, D. E., & Currie, W. B. (1987). Regulation of nutrient partitioning and metabolism during pre-and postnatal growth. Journal of Animal Science, 65(suppl_2), 186-212. https://doi.org/10.1093/ansci/65.suppl_2.186
Ding, L. M., Chen, J. Q., Degen, A. A., Qiu, Q., Liu, P. P., Dong, Q. M., Shang, Z. H., & Liu, S. J. (2016). Growth performance and hormonal status during feed restriction and compensatory growth of Small-Tail Han sheep in China. Small Ruminant Research, 144(1), 191-196. https://doi.org/10.1016/j.smallrumres.2016.09.018
Dougherty, H. C., Evered, M., Oltjen, J. W., Hegarty, R. S., Neutze, S. A., & Oddy, V. H. (2022). Effects of dietary energy density and supplemental rumen undegradable protein on intake, viscera, and carcass composition of lambs recovering from nutritional restriction. Journal of Animal Science, 100(7), 1-16. https://doi.org/10.1093/jas/skac158
Hallgren, K. A. (2012). Computing inter-rater reliability for observational data: an overview and tutorial. Tutorials in Quantitative Methods for Psychology, 8(1), 1-21. https://doi.org/10.20982/tqmp.08.1.p023
Harvey, N. D., Craigon, P. J., Sommerville, R., McMillan, C., Green, M., England, G. C., & Asher, L. (2016). Test-retest reliability and predictive validity of a juvenile guide dog behavior test. Journal of Veterinary Behavior, 11(1), 65-76. https://doi.org/10.1016/j.jveb.2015.09.005
Hicks, Z. M., Beer, H. N., Herrera, N. J., Gibbs, R. L., Lacey, T. A., Grijalva, P. C., Most, M. A., & Yates, D. T. (2021). Hindlimb tissue composition shifts between the fetal and juvenile stages in the lamb. Translational Animal Science, 5(1), 38-40. https://doi.org/10.1093/tas/txab164
Koo, T. K., & Li, M. Y. (2016). A guideline of selecting and reporting intraclass correlation coefficients for reliability research. Journal of Chiropractic Medicine, 15(2), 155-163. https://doi.org/10.1016/j.jcm.2016.02.012
Li, B., Sun, X., Huo, Q., Zhang, G., Wu, T., You, P., He, Y., Tian, W., Li, R., Li, C., Li, J., Wang, C., & Song, B. (2021). Pelleting of a total mixed ration affects growth performance of fattening lambs. Frontiers in Veterinary Science, 8(1), 1-13. https://doi.org/10.3389/fvets.2021.629016
McManus, C., Paim, T. D. P., Louvandini, H., Dallago, B. S. L., Dias, L. T., & Teixeira, R. A. (2013). Avaliação ultrasonográfica da qualidade de carcaça de ovinos Santa Inês. Ciência Animal Brasileira, 14(1), 8-16. https://doi.org/10.5216/cab.v14i1.12336
Nascimento, C. O., Santos, S. A., Pina, D. D. S., Tosto, M. S. L., Pinto, L. F. B., Eiras, D. N., Assis, D. Y. C., Perazzo, A. F., Araújo, M. L. G. M. L., Azevêdo, J. A. G., Mourão, G. B., & Carvalho, G. G. P. (2020). Effect of roughage-to-concentrate ratios combined with different preserved tropical forages on the productive performance of feedlot lambs. Small Ruminant Research, 182(1), 15-21. https://doi.org/10.1016/j.smallrumres.2019.11.002
Oliveira, K. A., Macedo-Júnior, G. L., Araújo, C. M., Siqueira, M. T. S., Araújo, M. J. P., & Jesus, T. A. V. (2019a). Productive parameters of growing lambs fed an extruded ration with different roughage: concentrate ratios. Semina Ciências Agrárias, 40(6), 3641-3652. https://doi.org/10.5433/1679-0359.2019v40n6Supl3p3641
Oliveira, K. A., Macedo-Júnior, G. L., Varanis, L. F. M., Araújo, C. M., Assis, T. S., Siqueira, M. T. S., & Sousa, L. F. (2019b). Nutritional parameters of lambs fed extruded ration with different roughage to concentrate ratios. Semina: Ciências Agrárias, 40(5), 1979-1990. https://doi.org/10.5433/1679-0359.2019v40n5p1979
Oliveira, K. A., Sousa, J. T. L., Sousa, L. F., Silva, A. L., Varanis, L. F. M., & Macedo-Júnior, G. L. (2020). Extruded feed in different volume-concentrate ratios: in-vitro fermentation kinetics, consumption, and evaluation of lambs’ metabolic profile. Veterinária Notícias, 26(2), 135-153. https://doi.org/10.14393/VTN-v26n2-2020-46321
Oliveira, B. Y. S., Moura, C. M. S., Araújo, G. G. L., Turco, S. H. N., Voltolini, T. V., Furtado, D. A., Medeiros, A. N., Gois, G. C., & Campos, F. S. (2024). Thermoregulatory responses and ingestive behavior of sheep subjected to water restriction and high-and low-energy diets in a semi-arid environment. Journal of Thermal Biology, 119(1), e103749. https://doi.org/10.1016/j. Jtherbio.2023.103749
Oliveira, K. A., Siqueira, M. T. S., Ribeiro, P. H. C., Araújo, L. C., Andrade, V. G., Vilaça, L. E. G., Oliveira, M. R., Faria, L. O., Schultz, E. B., & Macedo-Júnior, G. D. L. (2025). Feeding behavior and metabolic parameters of lambs fed extruded diets in different roughage: concentrate ratios. Semina Ciências Agrárias, 46(2), 443-458. https://doi.org/10.5433/1679-0359.2025v46n2p443
Parente, H. N., Parente, M. O. M., Gomes, R. M. S., Sodré, W. J. dos S., Moreira-Filho, M. A., Rodrigues, R. C., Santos, & V. L. F., Araújo, J. S. (2016). Increasing levels of concentrate digestibility, performance and ingestive behavior in lambs. Revista Brasileira de Saúde e Produção Animal, 17(2), 186-194. https://doi.org/10.1590/S1519-99402016000200006
Ponnampalam, E. N., Priyashantha, H., Vidanarachchi, J. K., Kiani, A., & Holman, B. W. (2024). Effects of nutritional factors on fat content, fatty acid composition, and sensorial properties of meat and milk from domesticated ruminants: an overview. Animals, 14(6), 1-38. https://doi.org/10.3390/ani14060840
Ribeiro, P. H. C., Oliveira, K. A., Siqueira, M. T. S., Araujo, L. C., Faria, L. D. O., Oliveira, M. R., Vilaça, L. E. G., Schultz, E. B., & Macedo-Júnior, G. D. L. (2025). Productive, behavioral and metabolic parameters of sheep fed with different roughage: concentrate ratios in fully extruded diets. Semina Ciências Agrárias, 46(3), 983-998. https://doi.org/10.5433/1679-0359.2025v46n3p983
Rodrigues, G. R. D., Siqueira, M. T. S., Oliveira, K. A., Oliveira, M. R., Schultz, E. B., & Macedo-Júnior, G. L. (2022). Extrused soybean hull as replacement for corn silage - nutritional and biochemical parameters in sheep. Revista Agrária Acadêmica, 5(1), 147-162. https://doi.org/10.32406/v5n1/2022/147-162/agrariacad
Russel, A. J. F., Doney, J. M., & Gunn, R. G. (1969). Subjective assessment of body fat in live sheep. Journal of Agricultural Science, 72(3), 451-454. https://doi.org/10.1017/S0021859600024874
Shao, X., Lu, X., Sun, X., Jiang, H., & Chen, Y. (2024). Preliminary studies on the molecular mechanism of intramuscular fat deposition in the longest dorsal muscle of sheep. BMC Genomics, 25(1), 592. https://doi.org/10.1186/s12864-024-10486-w
Silva, D. A. P., Santana, A. G., Araújo, C. M., Oliveira, K. A., Siqueira, M. T. S., & Macedo-Júnior, G. L. (2020). Evaluation of the nutritional and metabolic effects of replacing corn silage with extruded feed of grass marandu (Urochloa brizantha) in sheep. Caderno de Ciências Agrárias, 12(1), 1-9. https://doi.org/10.35699/2447-6218.2020.19833
Silva, D. A. P., Rodrigues, G. R. D., Siqueira, M. T. S., Schultz, E. B., Oliveira, K. A., & Macedo-Júnior, G. L. (2021). Evaluation replacement of corn silage by extruded roughage on sheep diet. Caderno de Ciências Agrárias, 13(1), 1-10. https://doi.org/10.35699/2447-6218.2021.32930
Silva, D. A. D. P., Loreno, M. B. N., Schultz, E. B., Siqueira, M. T. S., Oliveira, K. A., & Macedo-Júnior, G. D. L. (2023). Replacing corn silage with extruded forage in sheep feeding. Acta Scientiarum Animal Sciences, 45(1), e57397. https://doi.org/10.4025/actascianimsci.v45i1.57397
Silva, R. F., Ribeiro, P. H. C., Silva, Y. S., Soares, M. A. L., Ribeiro, C. V. M., Rangel, A. H. N., Ferreira, M. A., Emerenciano-Neto, J. V., & Urbano, S. A. (2024). Weight development and growth curves of grazing Santa Inês sheep supplemented with concentrate in the pre-weaning phase. Animals, 14(12), 1-10. https://doi.org/10.3390/ani14121766
Siqueira, M. T. S., Oliveira, K. A., Schultz, E. B., Sousa, L. F., Silva, V. R. S., & Macedo-Júnior, G. L. (2022). Evaluation of the effect of replacement of corn silage by extrused cane fiber ration in sheep. Revista Agrária Acadêmica, 5(1), 163-177. https://doi.org/10.32406/v5n1/2022/163-177/agrariacad
Zhang, C., Li, M. M., Al-Marashdeh, O., Gan, L. P., Zhang, C. Y., & Zhang, G. G. (2019). Performance, rumen fermentation, and gastrointestinal microflora of lambs fed pelleted or unpelleted total mixed ration. Animal Feed Science and Technology, 253(1), 22-31. https://doi.org/10.1016/j.anifeedsci.2019.05.003
Authors
Copyright (c) 2026 Tropical Animal Science Journal

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Authors submitting manuscripts should understand and agree that copyright of manuscripts of the article shall be assigned/transferred to Tropical Animal Science Journal. The statement to release the copyright to Tropical Animal Science Journal is stated in Form A. This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License (CC BY-SA) where Authors and Readers can copy and redistribute the material in any medium or format, as well as remix, transform, and build upon the material for any purpose, but they must give appropriate credit (cite to the article or content), provide a link to the license, and indicate if changes were made. If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original.