Prediction of bulk milk fatty acid composition based on farming practices collected through on-farm surveys

Abstract

The aim of this study was to predict the fatty acid (FA) composition of bulk milk using data describing farming practices collected via on-farm surveys. The FA composition of 1,248 bulk cow milk samples and the related farming practices were collected from 20 experiments led in 10 different European countries at 44°N to 60°N latitude and sea level to 2,000 m altitude. Farming practice-based FA predictions [coefficient of determination (R(2)) >0.50] were good for C16:0, C17:0, saturated FA, polyunsaturated FA, and odd-chain FA, and very good (R(2) ≥0.60) for trans-11 C18:1, trans-10 + trans-11 C18:1, cis-9,trans-11 conjugated linoleic acid, total trans FA, C18:3n-3, n-6:n-3 ratio, and branched-chain FA. Fatty acids were predicted by cow diet composition and by the altitude at which milk was produced, whereas animal-related factors (i.e., lactation stage, breed, milk yield, and proportion of primiparous cows in the herd) were not significant in any of the models. Proportion of fresh herbage in the cow diet was the main predictor, with the highest effect in almost all FA models. However, models built solely on conserved forage-derived samples gave good predictions for odd-chain FA, branched-chain FA, trans-10 C18:1 and C18:3n-3 (R(2) ≥0.46, 0.54, 0.52, and 0.70, respectively). These prediction models could offer farmers a valuable tool to help improve the nutritional quality of the milk they produce.

Effect of phenological stage and proportion of fresh herbage in cow diets on milk fatty acid composition

“…However, the results obtained in this study are in line with the results on the effect of fresh herbage proportions in cow diets demonstrated by Couvreur et al (2006) in controlled conditions or in on-farm conditions in other territorial contexts (i.e. Ferlay et al, 2008;Coppa et al, 2012Coppa et al, , 2013.…”

The effect of cattle breed, season and type of diet on the fatty acid profile of raw milk

“…Similarly, in their subsequent study Frelich et al (2012) mentioned lower content of C12:0, C14:0, C15:0 and C16:0 and higher content of C18:0 in grazing herds in comparison to indoor kept herds (P < 0.05). According to Dewhurst et al (2006) and Coppa et al (2013), a lower amount of C16:0 in milk from feeding of fresh herbage is a well-known and wellpredicted trend that is attributed to a lower C16:0 proportion in herbage in comparison to maize silage (Elgersma et al, 2006).…”

“…Furthermore, changes in BCFAs that originate from rumen fermentation can be well predicted by an increase in fresh herbage and hay and a decrease in maize silage and concentrates in the cows' diet (Coppa et al, 2013) because high-neutral detergent fibre diets (such as fresh herbage-based diet) favour ruminal populations of cellulolytic bacteria instead of the amylolytic bacteria favoured by starch-rich diets (Vlaeminck et al, 2006). Furthermore, the FA profile of milk fat can be influenced by the FA composition of pastures, which is dependent upon species, variety, growing conditions and forage maturity, as well as by grazing management strategies implemented at the farm level such as timing of cutting or grazing (Chouinard et al, 1998;Dewhurst et al, 2003;Elgersma et al, 2006;Ferlay et al, 2006).…”

“…The abovementioned studies showed the possibility of altering FA profile of milk fat. However, as Coppa et al (2013) pointed out, the majority of studies investigating the effect of diet and animal-related factors on milk FA profile were controlled trials not always reflecting common practice in commercial farms or applying measurements of farming practices not suitable on farms. Thus, the aim of the study was to determine the effect of the two predominant breeds reared in the Czech Republic and the effects of season and feeding management on the fatty acid profile of raw bovine milk.…”

DairyCant: a model for the reduction of dairy farm greenhouse gas emissions

“…The milk quality parameters are expressed as fatty acid (Coppa et al, 2013), fat, protein, urea concentration in the milk, based on the diet components for the flock. The energy cost represented by the excess of urea and its equivalent in litres is also estimated.…”