Effect of energy balance profiles on metabolic and reproductive response in Holstein and Swedish Red cows

This study examined the effect of two feeding levels during the antepartum and postpartum period on reproductive performance and blood metabolites (glucose, non-esterified fatty acids (NEFA), insulin) in primiparous Holstein and Swedish Red (SRB) cows, in order to identify possible differences in the way these breeds respond to negative energy balance after calving. A total of 44 cows (22 Holstein, 22 SRB) kept in a loose housing system were included in the study. The control group (HE, n = 23) was fed a diet for high-producing cows (target 35 kg/d energycorrected milk, ECM). A lower feeding intensity (LE, n = 21) was achieved by giving -50% concentrate to target 25 kg/d ECM. Diets were implemented 30 days before expected calving and the cows were monitored for 120 days postpartum. Milk yield and composition, dry matter intake (DMI), live body weight and body condition score (BCS) were assessed to calculate the weekly energy balance (residual feed intake). Blood sampling started before diet implementation and was repeated every 2 weeks until Day 60 postpartum and then once monthly until Day 120. Plasma was kept at −20 °C until analysis for glucose, insulin and NEFA concentrations. Mixed linear models were used to analyse data (SAS 9.3; PROC MIXED). Holstein cows had lower mean energy balance than SRB cows (−4.7 ± 1.4 and −0.9 ± 1.4 MJ, respectively; p = 0.05). SRB cows had higher (p<0.001) BCS (3.3 ± 0.1) than Holstein cows (2.7 ± 0.1) and also higher plasma glucose concentrations from Day -30 to Day 120 relative to parturition (4.1 ± 0.1 and 4.2 ± 0.1 log ; mg/100 ml, respectively; p < 0.05). Overall, breed or diet had no effect on NEFA blood plasma concentrations. However, plasma NEFA concentration levels tended to be higher (p = 0.09) in SRB cows than in Holsteins at Day -14 before calving, indicating higher mobilisation of lipid from adipose tissue already before calving. In contrast, Holstein cows had higher NEFA at Day 14 postpartum than SRB cows (p < 0.05). There were no significant effects of diet or breed on reproductive performance (% pregnant at first AI, days open). However, commencement of luteal activity within 21d postpartum was affected (p < 0.05) by the interaction of breed and diet. These results suggest that Holstein cows prioritise milk production to a larger extent than SRB cows, resulting in a less balanced metabolic profile

Effects of feed intensity and breed on postpartum blood metabolites

International audienc

Lack of impact of low energy diets on metabolomic analysis of cow follicular and uterine fluids

International audienc

Involvement of plasma adipokines in metabolic and reproductive parameters in Holstein dairy cows fed with diets with differing energy levels

Remerciements : INRA, UMR 0085, Plateforme PIC, 37380 Nouzilly, Centre de Tours Val de LoireThis study aimed to investigate the association between plasma adipokine concentrations and metabolic and reproductive parameters in Holstein dairy cows fed diets with different energy levels during the peripartum period. The experiment started 1 mo before first calving and was maintained for 2 lactations. Dry matter intake and energy balance in animals fed a low-energy (LE) diet were significantly lower than that of animals fed a high-energy (HE) diet in the first lactation. Body weight, milk production, back fat thickness, and plasma concentrations of fatty acids, glucose, and insulin were not affected by diet, whereas plasma leptin and adiponectin concentrations were lower and plasma resistin concentrations higher in animals fed the LE diet. Unlike concentrations of adiponectin, plasma resistin concentrations were positively correlated with back fat thickness and plasma fatty acids concentrations and negatively correlated with dry matter intake and plasma leptin concentrations. No effect of diet was found on reproductive variables; that is, pregnancy rates at 35 or 90 d after artificial insemination (AI); numbers of small (3-5 mm), medium (>5 and ≤7 mm), and large (>7 mm) follicles; calving-to-AI and calving-to-calving intervals; and magnitude and duration of the LH surge. However, the commencement of luteal activity after first calving occurred sooner and the frequency of LH pulses was higher in the HE group than in the LE group. A significant positive correlation was found between the number of follicles (of any size) and the area under the curve of plasma resistin concentrations. The number of small follicles was also positively correlated with the nadir of plasma resistin concentrations. Taken together, these results suggest that dietary energy content in the range applied here can alter the resumption of ovarian activity and LH pulsatility without affecting fat mobilization. Plasma adipokine profiles (leptin, resistin, and adiponectin) were significantly altered by diet and negative energy balance but relationships with reproductive variables were limited to follicular growth characteristics and plasma resistin concentrations