Nutritional supplementation with dietary omega-3 PUFA-rich flaxseed and canola oils enhances prime lamb performance and meat quality

Nguyen, Don Viet (2018) Nutritional supplementation with dietary omega-3 PUFA-rich flaxseed and canola oils enhances prime lamb performance and meat quality. PhD thesis, James Cook University.

[img]
Preview
PDF (Thesis)
Download (4MB) | Preview
View at Publisher Website: https://doi.org/10.25903/5bdbb8cf3573f
 
95


Abstract

This thesis tested the effects of supplementation with graded levels of either canola or flaxseed oils and their interactions with lamb breed and sex on Australian prime lamb productivity and product quality. It was hypothesised that supplementation of prime lambs with oil would interact with lamb breed and sex to: (1) positively impact feed intake, body conformation, growth and carcass indices of lamb productivity; and (2) alter plasma metabolites, wool and meat eating quality traits, and the fatty acid (FA) profiles of lamb tissues and organs including Longissimus dorsi muscle, visceral adipose tissue, heart, liver and kidney. Independent effects of breed and sex on productivity and product quality of lambs were also investigated.

Sixty dual-purpose prime lambs comprising purebred Merinos and Corriedale x Merino and White Suffolk x Merino crossbreds were allocated to one of five treatments of lucerne hay basal diet supplemented with isocaloric and isonitrogenous wheat-based pellets. Treatments were: no oil inclusion (Control); 2.5% canola oil; 5% canola oil; 2.5% flaxseed oil and 5% flaxseed oil, with lamb groups balanced by breed and gender. Each lamb was daily supplemented with one kg of pellets and had free access to lucerne hay and water throughout the 7-week feeding trial, after a 3-week adaptation. Individual animal basal and supplementary pellet feed intakes were recorded daily, while body conformation traits, body condition scores and liveweights were measured on days 0, 21, 35 and 49. The lambs were dye-banded on the mid-side and shorn before commencing the feeding trial and mid-side wool samples were collected from the same dye-banded area of each lamb at the end of the experiment. Plasma metabolites, fatty acids and carcass data were determined from blood, muscle, adipose, heart, kidney and liver samples at slaughter. All investigated parameters were analysed using the Statistical Analysis System (SAS) software version 9.2. General Linear Model (PROC GLM) analyses were used to fit oil supplementation, lamb breed, gender and their second-order interactions as fixed effects and measured traits associated with growth, body conformation, carcass characteristics wool, plasma metabolites and FA profile as dependent variables. In each case, linear and cubic orthogonal contrasts were interrogated and where any fixed effect was not a significant factor, it was removed from the final analytical model since it was not a variance contributor to the observed variation.

It was evident from the series of 5 experimental studies that supplementation of prime lambs with graded levels of canola and flaxseed oils, breed and sex significantly influenced productivity and product quality in Australian prime lambs, in which:

(1) Oil supplementation had no detrimental effect on growth performance, body conformation, wool quality, carcass characteristics, plasma metabolites and sensory attributes of meat eating quality;

(2) the supplementation of 5% flaxseed oil or canola oil into lamb diets decreased the omega- 6/omega-3 (n-6/n-3) ratio and increased the content of the health beneficial omega-3 longchain polyunsaturated fatty acids (n-3 LC-PUFA) in Longissimus muscle;

(3) Supplementing of 5% flaxseed oil into lamb diets reduced n-6/n-3 ratio in all investigated tissues and improved total n-3 PUFA composition in kidney, liver and visceral adipose;

(4) meat from lamb fed 5% flaxseed oil or canola oil reached the claimable 'source' level of n-3 LC-PUFA, and liver and kidney could be consumed as alternative 'good sources' of n-3 LC-PUFA;

(5) lamb breed and sex were imperative to influencing lamb growth, carcass, wool and meet eating quality, FA profiles of edible tissues and plasma metabolites; and

(6) interaction effects between oil supplementation and lamb breed on ADG and feed conversion ratio, visceral adipose and heart FA composition and meat juiciness score were detected. As a result, the hypothesis was accepted.

In conclusion, both canola and flaxseed oils can be effectively used in the prime lamb industry without any detrimental effect on productivity and product quality during a ten-week feedlot period. Furthermore, the observed interaction effects of oil supplementation with breed permit flexibility in operational options of optimising profitability from meat in prime lamb production. These findings suggest that prime lamb producers can better manage and match their breeding goals with feed resources. Therefore, a combination of 5% oil supplementation and lamb genetics is an effective and strategic management tool for improving feed efficiency, growth performance, and the content of n-3 LC-PUFA in lamb meat.

Item ID: 56014
Item Type: Thesis (PhD)
Keywords: adipose tissue, alpha linolenic acid, body conformation, canola oil, canola, dietary supplementation, dressing percentage, feed intake, flaxseed oil, flaxseed, lamb, n-3 LC-PUFA, oil supplementation, omega-3 fatty acids, omega-3 long-chain polyunsaturated fatty acids, plasma metabolites, prime lamb, supplementation, visceral organs
Related URLs:
Copyright Information: Copyright © 2018 Don Viet Nguyen
Additional Information:

Publications arising from this thesis are available from the Related URLs field. The publications are:

Nguyen, Don V., Malau-Aduli, Bunmi S., Cavalieri, John, Nichols, Peter D., and Malau-Aduli, Aduli E.O. (2018) Supplementation with plant-derived oils rich in omega-3 polyunsaturated fatty acids for lamb production. Veterinary and Animal Science, 6. pp. 29-40.

Nguyen, Don V., Malau-Aduli, Bunmi S., Nichols, Peter D., and Malau-Aduli, Aduli E.O. (2018) Growth performance and carcass characteristics of Australian prime lambs supplemented with pellets containing canola oil or flaxseed oil. Animal Production Science, 58 (11). pp. 2100-2108.

Nguyen, Don V., Le, Van H., Nguyen, Quang V., Malau-Aduli, Bunmi S., Nichols, Peter D., and Malau-Aduli, Aduli E.O. (2017) Omega–3 long-chain fatty acids in the heart, kidney, liver and plasma metabolite profiles of Australian prime lambs supplemented with pelleted canola and flaxseed Oils. Nutrients, 9 (8). pp. 1-17.

Date Deposited: 02 Nov 2018 03:52
FoR Codes: 07 AGRICULTURAL AND VETERINARY SCIENCES > 0702 Animal Production > 070204 Animal Nutrition @ 100%
SEO Codes: 83 ANIMAL PRODUCTION AND ANIMAL PRIMARY PRODUCTS > 8303 Livestock Raising > 830310 Sheep - Meat @ 100%
Downloads: Total: 95
Last 12 Months: 21
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page