Short Communications / Kort Mededelings Chemical composition of carcass sawdust residue as a predictor of the chemical composition of sheep carcasses

Abstract

Twenty sheep, ranging in body mass from 25 to 62 kg, were slaughtered to compare two methods of estimating the chemical composition of the carcassO. ne half of eachc arcassw as groundi n a carcass grinder equipped with a 6 mm sieve and a representatives ample taken. The other half was frozen. The complete frozen half was saweda t 25 mm intervalsi nto 'chop' portionsw ith a bandsawT. he tissue residue in the saw was collected. Moisture, fat, protein and ash percentageosf the samplesw ere determinedT. he meanc omposition of the groundc arcassa nd sawdusts amplesw ere respectivelym: oisture: 56.4 and 55.j%o (/ = 0.137); fat 21.2 and 23.l7o (/ = 0.923); protein: 16.6 and l6.1Vo (/ = 0.154) and ash: 4.7 and 5.5Vo (y' = 0.235).T he correlationsb etweens amplingt echniquesc omparew ell with similarc omparisonso btainedfr om studiesw ith cattlea ndp igs. This suggeststh at a reliablee stimateo f the fat and moisturec ontent of the carcass can be obtained from the sawdust residue. The techniquec an be recommendedfo r use in growth and feedingt rials with sheepa t locationsw here sophisticatedin strumentsa re not available to measurec arcassc omposition.

Twintig skape met 'n liggaamsmassvaa n tussen2 5 en 62 kg is geslago m twee metodeso m die chemieses amestellingv an karkasse te bepaal, te vergelyk. 'n Halwe karkas van elk is in 'n karkasmeule met 'n 6 mm sif gemaal en 'n monster is geneem. Die ander helfte is gevriesD. ie heelg evriesdeh elftei s in 25 mm 'kotelet'-stukkme et'n bandsaagg esaage n 'n monsteri s van die weefselresiduin die saag geneem.V og-, vet-, proteien- en asbepalingsv an die monstersi s gedoen. Die gemiddelde samestelling van die gemaalde- en saagmonstersw as respektieweliks oos volg: vog: 56.4 en 55.0Vo(f = 0.137);v et: 2l .2 en 23.17o( y' = 0.923):p roteien:1 6.6e n 16.lVo( y' = 0.154) en as: 4.7 en 5.57oG = 0.235).D ie korrelasiestu ssen metodes van monsterneming stem goed ooreen met soortgelyke vergelykingsv an bees-e n varkkarkasseD. ie resultated ui daaropd at die saagresidu-metodvea n monsternemingb etroubares kattingsv an die vet- en voginhoud van skaapkarkassgee e. Die metodek an by groei- en voedingsproewem et skapea anbeveewl ord in omstandighedew aar gesofistikeerdein strumenteo m die bepalingst e doen,n ie beskikbaairs nie.

Keywords: Carcass chemical composition, fat, protein, ash, sawdust residue, sheep.