AUTHOR=Justino Evandra da Silva , Santos Edson Mauro , Abreu Matheus Lima Corrêa , Herbster Caio Julio Lima , Brito Neto Antonio de Sousa , Marcondes Marcos Inácio , Silva Luciano Pinheiro da , Bezerra Leilson Rocha , Santos Stefanie Alvarenga , Oliveira Ronaldo Lopes , Pereira Elzania Sales 

TITLE=Trace minerals for maintenance and weight gain in male and female hair sheep

JOURNAL=Frontiers in Animal Science

VOLUME=Volume 6 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/animal-science/articles/10.3389/fanim.2025.1624560

DOI=10.3389/fanim.2025.1624560

ISSN=2673-6225

ABSTRACT=The objective of this study was to estimate the net requirements for gain (NCug, NFeg; NMng; NZng, NCog, and NCrg) and maintenance (NCum, NFem; NMnm, NZnm, NCom; and NCrm) in males and female hair sheep. Data from six studies, comprising 248 individual records (139 non-castrated males, 75 castrated males, and 34 females), were used to estimate net trace mineral requirements for weight gain. For maintenance requirements, 52 observations (26 intact and 26 castrated males) were analyzed. A meta-analytical approach was employed, incorporating non-linear mixed-effects models with the study treated as a random effect. Model selection was guided by the corrected Akaike information criterion (AICc) and some AICc-derived functions (Akaike difference, model probability, evidence ratio, and number of parameters of the fitted combination), which indicated that heterogeneous variance functions provided a better fit, with minimal model selection uncertainty. The final models selected effectively accounted for variability associated with sex and exhibited high confidence levels (model weights w ≥ 0.9), supporting their adequacy in describing trace mineral requirements. Sex did not affect the intercept and slope of the linear equations, and the net mineral requirements for maintenance were 34.85, 39.63, 6.11, 194, 6.06, and 11.67μg/kg of BW for Cu, Fe, Mn, Zn, Co, and Cr, respectively. The Fe requirements for gain decreased with increasing BW from 10 to 30 kg and average daily gain (ADG) of 150 g/day, ranging from 11.54 – 8.93; 10.58- 6.81; 7.16-2.91 mg for non-castrated males, castrated males, and females, respectively. The estimated dietary requirements for males with a BW of 30 kg and an average daily gain of 150 g were 69.6 mg/day for Fe;76.06 mg/day for Mn, and 2.62 mg/day for Co. Nutritional requirements for growth differ among castrated male, non-castrated male and female sheep for Fe, Mn, Zn and Cr. Thus, this study represents a significant advancement in the recommendation of nutritional requirements for trace elements in sheep breeds raised in tropical conditions.