Semina: Ciências Agrárias (May 2021)

Anthelmintic activity of the ethanolic extract of Carapa guianensis (Meliaceae) on gastrointestinal nematodes of sheep in the Western Amazon

  • Sara Lucena de Amorim,
  • Alex Cicinato Paulino de Oliveira,
  • Renato Mesquita Peixoto,
  • Maria Antonia Ferreira Moniz Pereira,
  • Lucas da Silva Bastos,
  • Cleb Rocha,
  • Ana Célia Rodrigues Athayde,
  • Wilson Wolflan Silva,
  • Maria do Carmo Medeiros

DOI
https://doi.org/10.5433/1679-0359.2021v42n4p2371
Journal volume & issue
Vol. 42, no. 4

Abstract

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The objective of this study was to evaluate the influence of energy supplementation on associative effects between forage and concentrate supplements and on the performance of beef cattle on a tropical pasture during the rainy season. Twenty-eight Nellore bulls averaging 19 months of age and 325.2 ± 4.1 kg were allotted to a completely randomized design and distributed into four paddocks of two hectares each with a tropical pasture for 84 d. The treatments consisted of bulls on Urochloa brizantha cv. Xaraés pasture without concentrate supplementation or bulls on Urochloa brizantha cv. Xaraés pasture receiving concentrate supplementation at 15 (S15), 30 (S30) or 45% (S45) of the total digestible nutrients (TDN) requirement. All bulls had ad libitum access to mineral supplementation. The amount and chemical composition of the supplement were adjusted every 28 d. Forage and supplement intakes were evaluated in all animals using fecal markers. Crude protein: digestible organic matter ratio decreased with supplementation; consequently, the imbalance between dietary protein and energy increased. Forage intake decreased with increasing supplementation. The substitution rates of pasture for supplementary feed were 0.14, 0.33, and 0.46 for bulls from S15, S30, and S45 treatments, respectively. However, the apparent DM digestibility increased linearly with supplementation level. Supplementation improved the assimilation of ammonia-N in the rumen. Energy supplementation for Nellore bulls on tropical pastures during the rainy season provides excess energy relative to protein, resulting in a substitution effect of supplement intake on forage intake. Moreover, energy supplementation does not improve body weight gain. Protein sources should be added to supplements for balancing protein and energy levels, thereby reducing a likely substitution effect.

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