A comparison of energy balance and metabolic profiles of the New Zealand and North American strains of Holstein Friesian dairy cow

Abstract

The milk production, energy balance (EB), endocrine and metabolite profiles of 10 New Zealand Holstein Friesian (NZ) cows and 10 North American Holstein Friesian (NA) cows were compared. The NA cows had greater peak milk yields and total lactation milk yields (7387 v. 6208 kg; s.e.d. 5 359), lower milk fat and similar protein concentrations compared with the NZ cows. Body weight (BW) was greater for NA cows compared with NZ cows throughout lactation (596 v. 544 kg; s.e.d. 5 15.5), while body condition score (BCS) tended to be lower. The NA strain tended to have greater dry matter intake (DMI) (17.2 v. 15.7 kg/day; s.e.d. 5 0.78) for week 1 to 20 of lactation, though DMI as a proportion of metabolic BW was similar for both strains. No differences were observed between the strains in the timing and magnitude of the EB nadir, interval to neutral EB, or mean daily EB for week 1 to 20 of lactation. Plasma concentrations of glucose and insulin were greater for NA cows during the transition period (day 14 pre partum to day 28 post partum). Plasma IGF-I concentrations were similar for the strains at this time, but NZ cows had greater plasma IGF-I concentration from day 29 to day 100 of lactation, despite similar calculated EB. In conclusion, the results of this study do not support the premise that the NZ strain has a more favourable metabolic status during the transition period. The results, however, indicate that NZ cows begin to partition nutrients towards body reserves during mid-lactation, whereas NA cows continue to partition nutrients to milk production.

Responses of North American and New Zealand strains of Holstein–Friesian dairy cattle to homeostatic challenges during early and mid-lactation

“…Differences in BCS profiles between the strains were less pronounced in the current study than previously documented (Harris and Horan et al, 2005). In the current study, both strains had comparable BCS loss during early lactation (T1), and had similar BCS in mid-lactation (T2); however, the NZ cows accumulated significantly more body reserves from T2 to the end of lactation (Patton et al, 2008).…”

“…This indicates greater insulin responsiveness in the NZ cows compared to NA cows in mid-lactation, as insulin resistance is associated with slower CR, longer t 1 2 and a greater AUC for glucose at similar insulin concentrations (Mertz, 1993). Greater insulin responsiveness in the NZ cows in mid-lactation is consistent with the accumulation of more body reserves from midlactation to the end of lactation (Patton et al, 2008).…”

“…at T1 (P 5 0.46) or at T2 (P 5 0.13). The milk production, post-partum EB and metabolic profiles of the animals used in the current study have been previously reported (Patton et al, 2008).…”

“…Plasma insulin Values reported are mean 6 s.d. and adapted from information previously reported in Tables 2 and 3 of Patton et al (2008).…”

Differences in the expression of genes involved in the somatotropic axis in divergent strains of Holstein-Friesian dairy cows during early and mid lactation

“…The liver is the major source of circulating insulin-like 18 growth factor's (Miller et al, 1981;Schwander et al, 1983;Thissen et al, 1994), and 19 therefore this organ plays a central role in the metabolism of the cow. 20 21 Numerous reports have suggested that nutritionally compromised cows have reduced 22 systemic concentrations of insulin and IGF-I (Patton et al, 2006;Lucy, 2008), and 23 Lucy et al (2009) reported that NAHF cows experience an uncoupling of the 24 somatotropic axis in conjunction with reduced BCS. It has been reported that 25 irreversible glucose loss leads to some degree of uncoupling of the somatotropic axis, 26 5 as plasma concentrations of IGF-1 decline concomitant with a reduction in hepatic 1 mRNA abundance of IGF-1 and GH receptor (GHR) (Meier et al, 2008).…”