Fat partitioning in British Friesian cows: the influence of physiological state on dissected body composition

Abstract

SummaryThe influence of physiological state (pregnant, lactating, dry) on body composition and fat partitioning in Friesian cows has been examined. A total of 20 cows, four per physiological state, were slaughtered and their left half carcasses dissected into individual muscles, bones and fat depots. All body parts, including the internal organs and fat depots, were weighed at slaughter.Muscle tissue and the internal organs showed some weight changes, consistent with a redistribution of tissue towards the udder and gut, and mobilization of muscle, but the major changes in weight associated with changing physiological state occurred in total body fat.Intermuscular fat made the greatest absolute contribution to changing fat weight, but subcutaneous fat showed the greatest proportional change with changing physiological state. The order of depletion of fat depots during fat loss was approximately the reverse of the order of development found during developmental growth.The distribution of subcutaneous fat between seven defined regions of the carcass was not affected by differences in total fatness in different physiological states. This, and the high correlation found between fat depth and total body fatness, confirms the view that measures of subcutaneous fat depth, e.g. by ultrasonics, should be useful predictors of the energy status of cows in varying physiological states.

Relationship between body condition score and body composition in dairy cows

“…It has been recommended that dairy farmers should aim to calve their cows when they have a condition score of 4 or more (Holmes et al 1987). During the first half of the lactation period, dairy cows in good body condition lose about 50% of their body fat reserves (Butler-Hogg et al 1985). A 50% loss of body fat in a cow which has a condition score of 4 would bring that cow close to a state which corresponds to depleted body fat reserves.…”

“…The extent to which such residual internal fat is accessible is not fully understood, but the lability of the different fat depots during lactation has been determined by Butler-Hogg et al (1985) for British Friesian cows which were in good condition. In that study, the rib and subcutaneous fats were the depots from which most fat was mobilised during early lactation when measured as a proportion of the fat for each depot that was present at the time of calving.…”

“…On an absolute basis this depot accounts for only 25% of the total body fat mobilised during early lactation (Butler-Hogg et al 1985). Intermuscular fat is the largest fat depot and contributes 39% of the total fat that is mobilised.…”

Dynamic model of the lactating dairy cow metabolism

“…Thus, the shape of the evolution in EBW was controlled so that it was close to an average curve as derived from results of a meta-analysis of lactation kinetics (Martin and Sauvant, 2002). Moreover, based on data of Komaragiri et al (1998), Komaragiri and Erdman (1997), Gibb et al (1992), Chilliard et al (1991), Butler-Hogg et al (1985), Martin and Ehle (1984) and Belyea et al (1978), it was assumed that the LIP and PRT compartments reached a minimum of, respectively, 65% and 90% of their initial pre-calving value during a standard lactation. Additionally, it was assumed that calving EBW was recovered by 300 days of a standard lactation.…”

Comparison of a classical with a highly formularized body condition scoring system for dairy cattle

“…Therefore, monitoring the energetic status and the quantity of the cow's fat storage is recommended (Bewley and Schutz, 2008). Subcutaneous adipose tissue seems to represent the proportional change of total body fat weight within the different physiological phases of the lactation cycle and therefore serves as a good indicator for major changes in total fat reserves (Butler-Hogg et al, 1985).…”