Supplementing Dairy Ewes Grazing Low Quality Pastures with Plant-Derived and Rumen-Protected Oils Containing Eicosapentaenoic Acid and Docosahexaenoic Acid Pellets Increases Body Condition Score and Milk, Fat, and Protein Yields

Abstract

Simple SummaryThis study evaluated the lactation performance and body condition scores of purebred Awassi and Awassi × East Friesian crossbred dairy ewes grazing low quality pastures and supplemented with diverse plant-derived oil enriched pellets under on-farm management conditions. The origin and treatment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to get the rumen protected EPA + DHA treatment was based on a modification of the microencapsulation of oil droplets in a protein-aldehyde matrix procedure. The results demonstrated that supplementation with rumen (EPA + DHA) and oil-infused pellets improved milk, fat, and protein yields by approximately 30%, 13%, and 31% respectively, and crossbred ewes produced more milk than purebreds. These results are very useful for dairy sheep producers in improving ewe lactation performance, milk quality, and body condition score under low quality pasture grazing conditions.AbstractThe Australian dairy sheep industry is small and mostly based on a natural grass grazing system, which can limit productivity. The current study tested different plant oil-infused and rumen protected polyunsaturated fats and their interactions with sire breeds to improve lactation traits and body condition scores (BCS) of ewes grazing low quality pastures. It was hypothesised that supplementing lactating ewe’s diets with plant-derived polyunsaturated oils would improve milk production and composition without compromising BCS. Sixty ewes (n = 10/treatment) in mid-lactation, balanced by sire breed, parity, milk yield, body condition score, and liveweight, were supplemented with: (1) control: wheat-based pellets without oil inclusion; wheat-based pellets including; (2) canola oil (CO); (3) rice bran oil (RBO); (4) flaxseed oil (FSO); (5); safflower oil (SFO); and (6) rumen protected marine oil containing eicosapentaenoic acid and docosahexaenoic acid (RPO). Except for the control group, all supplementary diets included the same level of 50 mL/kg DM of oil and all diets were isocaloric and isonitrogenous. Experimental animals were grazed in the same paddock with ad libitum access to pasture, hay, and water during the 10-week study. RPO was the most effective diet that enhanced milk, fat, and protein yields by approximately 30%, 13%, and 31%, respectively (p < 0.0001). A significant increase in milk production was also observed with CO, RBO, and SFO treatments (p < 0.0001). Breed significantly influenced animal performance with higher milk yields recorded for crossbred Awassi × East Friesian (AW × EF) (578 g/day) vs. purebred Awassi (452 g/day) (p < 0.0001). This study provides empirical evidence for the use of rumen-protected and plant-derived oil-infused pellets as supplements under low quality pasture grazing conditions to improve the production performance of purebred Awassi and crossbred AW × EF ewes.

Next Generation Sequencing of Single Nucleotide Polymorphic DNA-Markers in Selecting for Intramuscular Fat, Fat Melting Point, Omega-3 Long-Chain Polyunsaturated Fatty Acids and Meat Eating Quality in Tattykeel Australian White MARGRA Lamb

“…The proteins of the FABP4 family are small molecular-weight proteins that have a high binding affinity for long-chain fatty acids, participate in fatty-acid transportation from the plasma membrane to the sites of β-oxidation, triacylglycerol, and phospholipid synthesis, and variation in FABP4 gene has been reported to affect fat deposition, growth, and meat production in sheep [71,72]. Several other research findings in sheep have demonstrated that dietary manipulation of omega-3 fatty acids can influence intramuscular fat deposition, growth, milk, wool, and meat quality [42,[73][74][75][76][77][78][79][80][81][82][83][84][85][86][87][88][89][90], while only a handful of studies [52,[91][92][93] have validated independent associations of carcass quality, shear force, intramuscular fat percentage, and omega-3 polyunsaturated fatty acid content with gene markers or the expression of genes encoding enzymes regulating fat metabolism in Australian lamb. Therefore, our current findings at the FABP4 g.62829478A>-SNP locus showing consistently positive correlations between IMF and n-3 LC-PUFA of up to 0.66 with DHA, 0.47 with DPA, and 0.38 with EPA (Figure 9 and Tables 5 and 6) provides a novel molecular marker for TAW sheep producers to select and breed lambs that are not only of high meat-eating quality, but also provide a healthy product for brain growth and development.…”

Feeding and Nutritional Factors That Affect Somatic Cell Counts in Milk of Sheep and Goats

“…Some of the fatty acids present in these oils play important roles in anti-inflammatory processes, thereby improving the immunity status of udder. Sheep fed different vegetable oils presented a decrease in the SCCs in their milk [ 80 ], with the highest reduction found with flaxseed oil (−12.73%), followed by rice bran oil (−8.55%). The beneficial effect of flaxseed oil on the immune system has been well documented among cattle [ 81 , 82 ]: the oil increased IgG production via the improvement of immune function.…”

“…In fact, the disruption of mammary epithelium integrity and the tight junction opening can be assessed using plasma lactose concentrations and the Na+ content in milk [103]. These relationships were observed for hydrolysable tannins (−9.57% SCC and +1.95% lactose, Pulina et al [53]), rice bran (−8.55% SCC and +8.88% milk production) [80], and both doses of essential oils [84] in dairy sheep.…”

Effects of supplementary inulin on ewes milk composition and rumen fermentation parameters

“…The fat corrected milk (FCM) was calculated according to the equation of Nguyen et al . (2018) and the energy corrected milk (ECM) was calculated according to the equation of Sjaunja et al . (1990) and Tajaddini et al .…”

“…Milk samples were submitted to Ideh Sazan Rojan Alvand Co. (Karaj, Alborz, Iran) for fat, protein, lactose, solids-not-fat, MUN and fatty acid profile analyses using Fourier transform infrared spectroscopy (FTIR) (Delta CombiScope FTIR 600 HP, Delta Instruments, BV, Drachten, Netherlands). The fat corrected milk (FCM) was calculated according to the equation of Nguyen et al (2018) and the energy corrected milk (ECM) was calculated according to the equation of Sjaunja et al (1990) and Tajaddini et al (2021). The equations are reported in online Supplementary File.…”