Article

Muscle fiber, connective tissue and meat quality characteristics of pork from low birth weight pigs as affected by diet-induced increased fat absorption and preferential muscle marbling

Bimol Roy1,*, Patience Coleman1, Meghan Markowsky1, Kun Wang1,2, Yongbo She1,2, Caroline Richard1,2, Spencer Proctor1,2, Heather Bruce1
Author Information & Copyright
1Division of Animal Science, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton T6G 2P5, Canada.
2Division of Human Nutrition, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton T6G 2P5, Canada.
*Corresponding Author: Bimol Chandra Roy. E-mail: rimol@ualberta.ca.

© Copyright 2023 Korean Society for Food Science of Animal Resources. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: Jul 28, 2023 ; Revised: Sep 07, 2023 ; Accepted: Sep 15, 2023

Published Online: Sep 21, 2023

Abstract

This study investigated how birth weight differences in piglets affected carcass and muscle fiber properties as well as meat quality at slaughter. Within litters, piglets were grouped according to their birth weight as either normal (NBW; 1.62-1.73 kg) or low (LBW; 1.18-1.29 kg). At 5 weeks old, NBW piglets were randomly transitioned to control (C) or isocaloric high fat diets derived from non-dairy (HF), while LBW piglets were randomly transitioned to high fat diets derived from non-dairy (HF) or dairy sources (HFHD). Piglets were reared in individual pens under standardized housing and feeding conditions. Live weight was recorded weekly, and pigs were slaughtered at 12 weeks of age. Hot carcass weights, dressing percentages, lean meat yield, and primal cut proportions were determined. The m. longissimusthoracis was collected from the right side of the carcass for measurement of physical and chemical properties of meat and muscle fiber characteristics. Results indicated that LBW pigs compensated for their live weight compared to NBW pigs at 6 weeks of age. The mean muscle fiber diameter of LBW-HFHD group is significantly higher than NBW-C and NBW-HF group, and the type I muscle fiber diameter is significantly higher than NBW-C group. Dairy fat inclusion in LBW pig diet reduced carcass back fat thickness. This increased the calculated lean meat yield to be comparable to that of NBW pigs fed a commercial diet. Incorporating dairy sources high fat into LBW pigs' diets appears to be an effective strategy for producing carcasses equivalent to NBW pigs.

Keywords: pig; pork; carcass quality; birth weight; muscle fibers