Feeding Soybean Oil to Dairy Goats Increases Conjugated Linoleic Acid in Milk

Abstract

A total of 24 Murciano-Granadina dairy goats milked once daily throughout lactation were used to study the effects of including soybean oil (SBO) in the diet on lactational performance and milk fatty acid (FA) content, particularly conjugated linoleic acid (CLA) and trans-vaccenic acid (trans-11 C18:1, TVA). Three weeks after parturition, goats were allocated to 2 balanced groups according to lactation number, body weight, and daily milk yield, and were kept in separate pens. The experiment consisted of a 2-period (28 d each) crossover with 2 dietary treatments: control and SBO (6% as fed in the concentrate). Goats were fed dehydrated fescue (ad libitum), alfalfa pellets (0.5 kg/d), and concentrate (1 kg/d) to which the SBO was or was not added. Forage was fed in the pens, and concentrate was fed individually in 2 equal portions at milking (0900 h) and in the afternoon (1700 h). Final SBO content in the consumed SBO diet was 2.5% (dry matter basis). Diets were isonitrogenous (17.4% crude protein), but their total FA content varied from 2.2% (control) to 4.6% (SBO). There was no effect of SBO on dry matter intake, milk yield, energy-corrected milk, body weight, or body condition score. Compared with the control diet, feeding SBO increased milk fat content (4.57 vs. 5.24%) and yield as well as total solids content. Soybean oil had no effect on milk crude and true protein contents, but it reduced milk casein content (2.48 vs. 2.34%). Short- and medium-chain FA decreased by feeding SBO, whereas long-chain FA increased. Feeding preformed linoleic acid through SBO increased milk concentrations of linoleic, oleic, and stearic FA but reduced levels of linolenic and palmitic FA. As a consequence, feeding SBO decreased the saturated-to-unsaturated FA ratio and the atherogenicity index. Compared with the control treatment, milk contents of cis-9, trans-11 CLA (0.68 vs. 2.03%) and TVA (2.04 vs. 6.41%) in the SBO treatment increased by approximately 200%. In conclusion, feeding a moderate dose of SBO to dairy goats was a useful way to increase milk fat, CLA, and TVA contents in milk and to reduce the atherogenicity index without negative effects on intake, milk yield, and protein content.

Feeding vegetable oils to lactating ewes modifies the fatty acid profile of suckling lambs

“…The effects of SOY supplementation have already been well described in sheep (Gó mez-Cortes et al, 2008b) and goats (Bouattour et al, 2008), and similar results have been obtained from supplementing sheep diets with sunflower oil, which is rich in 18:2n-6 ). According to previous research, SOY-fed ewes displayed a nearly five-fold higher proportion of cis-9, trans-11 CLA than PALM-fed animals.…”

“…A decrease in medium-chain FAs (C12 to C16) and SFA was also observed, and de novo synthesis of SFA may have been inhibited by the presence of long-chain FAs in the diet (Bouattour et al, 2008;Gó mez-Cortes et al, 2008b;Castro et al, 2009). Using SOY in feed has been proposed as an alternative for producing milk and dairy products enriched in MUFA, cis-9, trans-11 CLA and trans-11 18:1 (Bouattour et al, 2008). Zhang et al (2006) described how inclusion of LIN in the diet increases 18:3n-3 and PUFA, and produces moderate increases in cis-9, trans-11 CLA and trans-11 18:1 levels in milk.…”

“…The impact of supplementation with vegetable oils on sheep milk and meat FA composition has been extensively studied in recent years (Bessa et al, 2005;Bouattour et al, 2008;Gó mez-Cortes et al, 2008a, 2008bManso et al, 2009). Suckling lamb meat is a delicacy in Mediterranean countries, and as such, there is an elevated demand for this high-quality product by consumers.…”

“…According to previous research, SOY-fed ewes displayed a nearly five-fold higher proportion of cis-9, trans-11 CLA than PALM-fed animals. A decrease in medium-chain FAs (C12 to C16) and SFA was also observed, and de novo synthesis of SFA may have been inhibited by the presence of long-chain FAs in the diet (Bouattour et al, 2008;Gó mez-Cortes et al, 2008b;Castro et al, 2009). Using SOY in feed has been proposed as an alternative for producing milk and dairy products enriched in MUFA, cis-9, trans-11 CLA and trans-11 18:1 (Bouattour et al, 2008).…”

Óleo de peixe em substituição parcial ao óleo de soja em dietas para ovinos

“…Outros autores observaram decréscimo no rendimento de proteína do leite em resposta ao fornecimento de óleo de peixe SHINGFIELD et al, 2003SHINGFIELD et al, , 2006 (ABUGHAZALEH et al, 2002;BOUATTOUR et al, 2008; EIFERT et al, 2006;FREITAS Jr. et al, 2010; HERBEIN, 2003;RAMASWAMY et al, 2001). …”