A High Dietary Incorporation Level of Chlorella vulgaris Improves the Nutritional Value of Pork Fat without Impairing the Performance of Finishing Pigs

Abstract

The influence of a high inclusion level of Chlorella vulgaris, individually and supplemented with two carbohydrase mixtures, in finishing pig diets was assessed on zootechnical performance, carcass characteristics, pork quality traits and nutritional value of pork fat. Forty crossbred entire male pigs, sons of Large White × Landrace sows crossed with Pietrain boars, with an initial live weight of 59.1 ± 5.69 kg were used in this trial. Swines were randomly assigned to one of four dietary treatments (n = 10): cereal and soybean meal-based diet (control), control diet with 5% C. vulgaris (CV), CV diet supplemented with 0.005% Rovabio® Excel AP (CV + R) and CV diet supplemented with 0.01% of a four-CAZyme mixture (CV + M). Animals were slaughtered, after the finishing period, with a BW of 101 ± 1.9 kg. Growth performance, carcass characteristics and meat quality traits were not influenced (p > 0.05) by the incorporation of C. vulgaris in the diets. However, the inclusion of the microalga in finishing pig diets increased some lipid-soluble antioxidant pigments and n-3 PUFA, and decreased the n-6:n-3 ratio of fatty acids, thus ameliorating the nutritional value of pork fat. Moreover, the supplementation of diets with the carbohydrase mixtures did not change (p > 0.05) neither animal performance nor meat quality traits, indicating their inefficacy in the increase of digestive utilization of C. vulgaris by pigs under these experimental conditions. It is concluded that the use of C. vulgaris in finishing pig diets, at this high incorporation level, improves the nutritional value of pork fat without compromising pig performance.

Effects of Chlorella vulgaris as a Feed Ingredient on the Quality and Nutritional Value of Weaned Piglets’ Meat

“…For instance, piglets’ diet receiving 5% of C. vulgaris combined with the four-CAZyme mixture could be a valuable source of these protective fatty acids to both animals and humans. Consistent with our findings, the dietary C. vulgaris at this level of incorporation also produced an increment in n -3 PUFA amount in finishing pigs [ 9 ]. The enhancement of n -3 PUFA content subsequently resulted in a positive decline in n -6/ n -3 ratio in muscle with incorporation of C. vulgaris in piglets’ diet.…”

“…In fact, the incorporation of this microalga led to higher content of pigments in the diets, in particular about 17 times more total carotenoids if compared with the reference diet. As highlighted by Coelho et al [ 9 ], the transfer of carotenoids from the microalga to the meat adds extra nutritional value to pork. Our data are in accordance with these authors, who also found 2 times higher total carotenoid contents in meat from finishing pigs fed with 5% of C. vulgaris .…”

“…The ingredients and chemical composition of diets are shown in Table 1 . The detailed chemical composition of C. vulgaris was previously described [ 9 ].…”

“…Fatty acids were converted to FAME through a combined alkaline and acid sequential transesterification, in accordance with Raes et al [ 26 ]. The fatty acid composition was analyzed by GC (HP6890A; Hewlett-Packard, Avondale, PA, USA), equipped with a flame ionization detector, as described [ 9 ]. The identification of FAME was achieved using a reference standard (FAME mixture of 37 compounds, Supelco Inc., Bellefonte, PA, USA) corroborated by GC along with mass spectrometry using a GC-MS QP2010-Plus (Shimadzu, Kyoto, Japan).…”

“…Rovabio ® Excel AP is a commercially available CAZyme mixture containing mainly xylanases and β-glucanases for cereal-based diets. This CAZyme mixture has also been used for microalgae-containing diets [ 8 , 9 ]. Moreover, a four-CAZyme mixture, consisting of alginate lyase, exo-β-glucosaminidase, lysozyme, and peptidoglycan N -acetylmuramic acid deacetylase, has been shown to partially disrupt the C. vulgaris cell wall in vitro [ 10 ].…”