Backfat Characteristics of Barrows and Gilts Fed on Tuna Oil Supplemented Diets during the Growing-finishing Periods

This study was conducted to evaluate the effect of supplementing tuna oil to diets of growing-finishing pigs (barrows and gilts) on backfat characteristics when slaughtered at different weights. Four hundred and eighty crossbred (Large White$\times$Landrace$\times$Duroc) pigs averaging 30 kg were allotted to 12 treatment combinations (40 pigs/treatment combination) in a completely randomized design with a $2{\times}2{\times}3$ factorial arrangement of treatments. The treatments were: dietary tuna oil supplementation (0 and 2%); sex (barrows and gilts); and slaughter weight (90, 100 and 110 kg). As pigs reached their slaughter weight, they were randomly selected (8 pigs/treatment combination; 96 pigs in total) and slaughtered. Backfat colour, hardness and fatty acid profile were assessed. There were significant (p