Effect of Spirulina (Arthrospira plantensis) Supplementation on Wool Quality in Purebred and Crossbred Merino Lambs Fed Pasture and Lucerne Hay Basal Diets

Abstract

This study investigated the effects of Spirulina (Arthrospira plantensis) supplementation level, basal diet, sire breed, and sex on wool quality parameters in purebred and crossbred Merino lambs. A total of 48 lambs, over two consecutive years (n=24 per year), was randomly allocated into Spirulina supplementation level (CONTROL, LOW, MEDIUM, HIGH) groups and balanced by sire breed (Black Suffolk, Dorset, Merino, White Suffolk) and sex (ewes, wethers). Lambs had ad libitum access to a basal diet of pasture and Lucerne hay, and had Spirulina supplement daily throughout the 42-day feeding trial, after a 21-day adjustment phase. Mid-side wool samples were removed from each lamb at the beginning and end of the feeding trial and commercially analysed for quality. The wool quality data were transformed into 'wool trait change over the feeding trial period' by the difference between the wool measurements at the beginning and end of the experiment prior to statistical analysis. Wool clean fleece weight (CFW) was significantly influenced by level of supplementation, basal diet and sex (P<0.05). Spirulina-supplemented lambs on Lucerne hay basal diet elicited higher CFW responses which increased with supplementation level. CONTROL lambs had the lightest CFW regardless of basal diet. Sire breed and sex variations were significant (P<0.05) as wool from Suffolk-sired lambs and ewes had the highest fibre diameter coefficient of variation (CV) and CFW, respectively. CV and fibre diameter standard deviation were the most affected wool traits by significant interactions between Spirulina supplementation level, sire breed and sex. It was concluded that Spirulina supplementation with Lucerne hay basal diet improves wool CFW without compromising wool fibre diameter, comfort factor and spinning fineness in dual-purpose prime lambs.

Correlations between growth and wool quality traits of genetically divergent Australian lambs in response to canola or flaxseed oil supplementation

“…The results of our previous findings from this same flock [22] were consistent with other studies [17, 22, 33–39] on growth traits related to meat production in lambs and had been presented in detail, hence will not be repeated herein. Apart from growth and meat production, wool products also contribute a significant percentage to economic returns in the dual-purpose sheep enterprise [40]. The additional data in the present study build upon previously published findings by providing new knowledge on the relationships between growth and wool parameters in the light of dietary oil supplementation, breed and gender effects.…”

“…Herein, we illustrate that wool is not a uniform biological product because its physical characteristics vary depending on sheep genetics, environment and management strategies [41]. Wool fibres are primarily composed of protein [42], thus wool synthesis is frequently influenced by the quality and amount of dietary protein, especially sulphur-containing amino acids–cysteine and methionine [40]. However, protein content was not impacted by the inclusion of canola oil or flaxseed oil [22].…”

Effect of Rearing Systems on Growth Performance and Wool Characteristics of Rahmani Sheep Lambs

“…Normally, the clean fleece weight refers to the fibrous content of wool and attracts high price premiums (Holman and Malau-Aduli 2012). Wool fibres are primarily composed of proteins (Plowman, 2003), hence it is possible that with increasing of protein-rich sources, there was a corresponding increase in nutrient partitioning towards wool fibre synthesis, hence the observed increase in clean fleece weight (Holman and Malau-Aduli 2014). Moreover, current differences detected in clean wool yield between the rearing systems, could be due to that lambs were not exposed to wool contaminants (such as vegetable matter and dust) which are known to decrease clean fleece weight (Holman and Malau-Aduli, 2012).…”