Mineral requirements for growth of wool and hair lambs

Author(s)

Molina de Almeida Teixeira, Izabelle Auxiliadora ^[1] ; de Resende, Kleber Tomas ^[1] ; de Azevedo Silva, Aderbal Marcos ^[2] ; da Silva Sobrinho, Americo Garcia ^[1] ; Haerter, Carla Joice ^[1] ; de Oliveira Sader, Ana Paula ^[1]

Affiliation

^[1] Univ Estadual Paulista, UNESP, Dept Anim Sci, BR-14884900 Jaboticabal, SP - Brazil

^[2] Univ Fed Campina Grande, CSTR, BR-58700970 Patos de Minas, PB - Brazil

• Document type: Journal article
• Source: REVISTA BRASILEIRA DE ZOOTECNIA-BRAZILIAN JOURNAL OF ANIMAL SCIENCE; v. 42, n. 5, p. 347-353, MAY 2013.
• Web of Science Citations: 6

Abstract

The present study was conducted to determine the body composition and the mineral requirements for growth of wool and hair lambs. A total of 34 castrated lambs with an initial body weight (BW) of 19.9 +/- 0.8 kg were used; 17 of these lambs were of the genotype Ideal x Ile de France and 17 were Santa Ines. Ten lambs (5 of each genotype) were slaughtered at the beginning of the experiment to establish their initial body composition. The remaining lambs were assigned to one of three diets (40% roughage and 60% concentrate, 60% roughage and 40% concentrate, or 80% roughage and 20% concentrate) in a 2 x 3 factorial arrangement of treatments. All of the diets were provided ad libitum. When the group under 40% roughage and 60% concentrate reached 35 kg BW, all of the animals were slaughtered. Linear regressions were used to determine the relationship between the shrunk BW and the empty body weight (EBW) for each genotype. These equations were compared and revealed differences between the genotypes. The allometric equations were calculated using the relationship between the amount of minerals and the EBW. The equations of a given mineral for each genotype were compared to verify if they were statistically different. The equations for calcium, phosphorus, magnesium and sodium differed between genotypes. The same equations were used to estimate the major body mineral composition per kilogram of EBW. The net requirement for gain of the fleece-free Ideal x Ile de France lambs ranged from 7.77 to 6.80 g Ca, 4.54 to 4.14 g P, 0.30 to 0.27 g Mg, 1.18 to 1.07 g K and 0.84 to 0.76 g Na per kg BW gain, and the requirements of the Santa Ines animals ranged from 9.57 to 8.37 g Ca, 5.39 to 4.91 g P, 0.36 to 0.33 g Mg, 1.18 to 1.07 g K and 0.90 to 0.81 g Na per kg BW gain for the lambs weighting 20 to 35 kg. Santa Ines lambs showed higher requirements for Ca, P, Mg and Na. (AU)