Feeding hydrogenated palm fatty acids and rumen-protected protein to lactating Holstein-Friesian dairy cows modifies milk fat triacylglycerol composition and structure, and solid fat content

Abstract

The aim of this study was to analyze the effect of fat and protein supplementation to dairy cattle rations on milk fat triacylglycerol (TAG) composition, fatty acid (FA) positional distribution in the TAG structure, and milk solid fat content (SFC). Fifty-six lactating Holstein-Friesian cows were blocked into 14 groups of 4 cows and randomly assigned 1 of 4 dietary treatments fed for 28 d: (1) low protein, low fat, (2) high protein, low fat, (3) low protein, high fat, and (4) high protein, high fat. The high protein and high fat diets were obtained by isoenergetically supplementing the basal ration (low protein, low fat) with rumen-protected soybean meal and rumen-protected rapeseed meal, and hydrogenated palm FA (mainly C16:0 and C18:0), respectively. Fat supplementation modified milk TAG composition more extensively compared with protein supplementation. Fat supplementation resulted in decreased concentrations of the low molecular weight TAG carbon number (CN) 26 to CN34 and medium molecular weight TAG CN40, CN44, and CN46, and increased concentrations of CN38 and the high molecular weight TAG CN50 and CN52. Increased contents of C16:0, C18:0, and C18: 1cis -9 in TAG in response to fat supplementation were related to increases in the relative concentrations of C16:0 and C18:0 at the sn-2 position and C18:0 and C18: 1cis -9 at the sn-1(3) positions of the TAG structure. Increased concentrations of high molecular weight TAG species CN50 and CN52 in response to fat supplementation was associated with increased milk SFC at 20, 25, and 30°C. Our study shows that important alterations in milk TAG composition and structure occur when feeding hydrogenated palm FA to lactating dairy cattle, and that these alterations result in an increased SFC of milk fat. These changes in milk SFC and TAG composition and structure may improve absorption of both fat and minerals in milk-based products for infants and may affect processing of milk fat.

The Changes in Fecal Bacterial Communities in Goats Offered Rumen-Protected Fat

“…RPFs are an important ingredient in the diets of ruminants, especially dairy cows [16]. It is well accepted that RPF benefits herd reproductive performance because they can increase energy density and reduce the risk of metabolic disorders [6,17].…”

Effects of Dietary Supplements of DHA-enriched Micro Algae Diet on Physical and Technological Properties of Dairy Cow Milk Fat

“…"Because of its great importance, studies have been carried out on the effect of feed supplementation on the physical properties of milk fat properties such as solid fat content (SFC). For instance, a decrease in the SFC of milk derived from cow fed full fat soybeans and rape seed" was reported [9,10] and was associated with a reduction in saturated fatty acid content and an increase in monounsaturated fatty acid content. Shazly et al [11] observed that "the physical properties of anhydrous milk fat (AMF) such as sold fat content (SFC) of cows and buffaloes supplemented with flaxseed oil (FO), soybean oil (SO), or their mixture (FSO) were affected not only by its content of USFA but also by its contents of lipid-minor components such as cholesterol and vitamin E".…”

Functional properties of cream and butter oil from milk of Holstein cows abomasally infused with increasing amounts of high-oleic sunflower fatty acids

“…The fatty acid (FA) and triglyceride (TG) composition of milk can be altered by manipulating the diet of lactating dairy cows (Banks et al ., 1989b; Lin et al ., 1996; DePeters et al ., 2001; Pacheco-Pappenheim et al ., 2022). Oleic acid content of milk fat increases linearly in response to increased intestinal supply of oleic acid to cows (Drackley et al ., 2007; LaCount et al ., 1994).…”

“…In addition to the FA composition of milk fat, the TG composition affects solid fat content and functional properties of milk fat (Banks et al ., 1989b; Gresti et al ., 1993; Pacheco-Pappenheim et al ., 2022). Effects of increasing oleic acid on milk TG profile might impact properties of dairy products (Banks et al ., 1989b), and may be the key for determining the type and amount of FA to be included in an altered milk fat to improve the nutritional quality of milk without risking the processing characteristics of a specific dairy product.…”