Ntallaris, Theodoros
- Institutionen för kliniska vetenskaper, Sveriges lantbruksuniversitet
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 ¼ 23) was fed a diet for high-producing cows (target 35 kg/d energycorrected milk, ECM). A lower feeding intensity (LE, n ¼ 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 ¼ 0.05). SRB cows had higher (p
Dairy cattle; Metabolic imbalance; Blood metabolites; Transition period; Reproductive efficiency
Theriogenology
2017, volym: 90, sidor: 276-283
Genetik och förädling inom lantbruksvetenskap
https://res.slu.se/id/publ/79622