Intramuscular collagen characteristics of ram, wether, and zeranol-implanted ram lambs

Abstract

Eighteen spring-born Columbia ram, wether, and zeranol-implanted ram lambs were studied to determine the influence of castration or zeranol implants on intramuscular collagen (IMC) properties and muscle shear force values. Warner-Bratzler shear force values for longissimus muscle were greatest for ram lambs, intermediate for implanted rams, and least for wethers (P < .05). Nonreducible collagen crosslink concentration was greater in IMC of rams and implanted rams (P < .05). The IMC from rams compared with that from wethers contained proportionately more Type III than Type I collagen (P < .05); values for implanted rams were intermediate. Heat-soluble muscle collagen concentration was greater for rams and implanted rams than for wethers (P < .05); however, insoluble collagen concentration did not differ by treatment. Muscle collagen concentrations were not different for rams, wethers, or implanted rams. Increased shear force values in rams were associated with elevated collagen crosslink concentration and increased proportion of Type III collagen. Greater concentration of soluble collagen in ram IMC neither diminished nor diluted IMC crosslinking. The proportion of heat-labile collagen in the fractions did not reflect the IMC crosslinking profile for ram and wether lambs. Zeranol implantation modified IMC characteristics of rams such that shear force values and some collagen properties were similar to those of wethers.

Efeito Do Peso Ao Abate De Cordeiros Santa Inês E Bergamácia Sobre as Características Físico-Químicas Da Carne

“…As variações encontradas na maciez são decorrentes de vários fatores, tais como: raça dos animais [21,23,27,30], peso ou idade ao abate [34,39], tipos de músculos [1,42], sistema de manejo [27,28,36] e condições de pré e pós-abate.…”

“…MAIORANO et al [27], verificaram que cordeiros castrados (1,64kg) apresentaram maior maciez, seguido por cordeiros implantados com Zeranol (2,01kg) e mostraram menor maciez os cordeiros inteiros (2,45kg). No entanto, PURCHAS [36] relatou que diferenças entre ovelhas, machos inteiros e castrados são pequenas ou inconsistentes.…”

Collagen characteristics of skin, fell, and epimysium from rams, wethers, and zeranol-implanted ram lambs

“…A primary structural attribute of collagen, determining many of its functional qualities, is crosslinking (Reiser et al, 1992). The hydroxylysylpyridinium ( HP) crosslink is relatively abundant in intramuscular collagens and has been used to measure the progression of crosslinking across a number of species in a variety of muscles (Smith and Judge, 1991;Horgan et al, 1991;Maiorano et al, 1993;McCormick, 1994). However, the HP crosslink is absent from skin collagen (Eyre et al, 1984;Yamauchi and Mechanic, 1988), present only in trace amounts in fell (McCormick, unpublished data), and occurs in relatively low levels (compared with intramuscular collagen) in epimysium (Horgan et al, 1991).…”

“…Six Columbia ram lambs left intact, six castrated at approximately 100 d of age, and six intact rams implanted with 12 mg of zeranol at 100 d of age were used in this study. The lambs were fed an 80% corn diet on an ad libitum basis for 70 d before slaughter at approximately 6 mo of age and a live weight of approximately 53 kg as described by Maiorano et al (1993).…”

Effects of biological type and dietary fat treatment on factors associated with tenderness: I. Measurements on beef longissimus muscle

“…Wide differences in cross-link type and concentration occur between different tissues and muscle types (McCormick, 1994). Maiorano et al (1993) reported that sex and age differences affect the amount of collagen and cross-linking in sheep. The current study with LM steaks from cattle of the same sex and relative age indicates that breed differences in tenderness could not be attributed to variation in collagen amount or the amount of cross-linking.…”