Once-daily milking during late lactation in pasture-fed dairy cows has minor effects on feed intake, body condition score gain, and hepatic gene expression

Abstract

Milking cows once daily (1×) is a management practice occasionally used during mid/late lactation in pasture-based systems. It has been postulated that 1× milking will reduce dry matter intake (DMI) and increase body condition score (BCS) gain; however, this has not been quantified. Lactating, pregnant Holstein-Friesian dairy cows (n=52) were allocated to either 1× or twice-daily (2×) milking in mid-January (summer, 175d in milk). To obtain accurate DMI measurements, cows underwent 4 periods in a Calan gate indoor feeding facility, interspersed with grazing outdoors. Milk production, body weight (BW), and BCS were recorded 2 wk before treatment start (-2 wk) and weekly thereafter. Blood variables were recorded at -2 wk and weekly when indoors. Liver was biopsied at -2, 2, and 10 wk, and hepatic gene expression measured using quantitative PCR. Milking cows 1× tended to lower DMI (17.8 vs. 18.2 kg of dry matter), but increased BCS gain (0.36 vs. 0.13 BCS units) and BW (546 vs. 533 kg) at wk 12 relative to 2×. The greater BCS and BW of cows milked 1× compared with 2× were reflected in lower plasma concentrations of nonesterified fatty acids and lower transcription of genes involved in the oxidation of fatty acids, indicating reduced release and processing of fatty acids. Cows milked 1× produced 20% less milk, and although milk fat and protein concentrations were increased relative to cows milked 2×, yields of fat and protein were 14 and 17% less, respectively. The reduction in milk production with 1× milking (14.1 vs. 16.8 kg/cow per d energy-corrected milk) was accompanied by increases in blood concentrations of glucose and insulin, with a concurrent decrease in the transcription of the insulin receptor and gluconeogenic genes. These results indicate a coordinated response to reduce glucose production due to decreased mammary demand. Expression of 2 genes linked to inflammation and adipokine signaling was reduced in cows milked 1× and may indicate a lower inflammatory state in the liver of cows milked 1× in late lactation. No effect was found of milking frequency during late lactation on milk production in the subsequent lactation. In summary, although 1× milking tended to reduce DMI and increase BCS in late lactation, these effects were lower than what is commonly supposed in pasture-based dairy systems. The modest BCS gains need to be considered with the reduced milk production when adopting 1× milking as a management strategy.

Reducing milking frequency from twice each day to three times each two days affected protein but not fat yield in a pasture-based dairy system

“…Interestingly, FS-3-in-2 yielded similar lactation yield percentage changes to short-term (3-8 wk) use of OAD in early lactation (Phyn et al, 2014;Kennedy et al, 2021), while requiring considerably fewer milkings, a result also reported by Woolford et al (1985). Previous studies (e.g., Grala et al, 2016) using OAD in late lactation have not included production information before the experimental period, meaning the effect on lactation yield cannot be discussed in relation to our results.…”

Physiologically based modelling of the pharmacokinetics of three beta‐lactam antibiotics after intra‐mammary administration in dairy cows

“…Variations to the traditional twice-daily milking regimen have become important in some production systems: some farms have instituted once-daily milking (Clark, Phyn, Tong, Collis, & Dalley, 2006;Grala et al, 2016), some farms use asymmetrical twice-daily milking such as alternating 14 and 10 hr inter-milking intervals (Chládek et al, 2014;Rémond, Pomiès, Julien, & Guinard-Flament, 2009), some farms have moved to thrice-daily milking (Allen, DePeters, & Laben, 1986), and robotic milking introduces randomness into the milking frequency (Løvendahl & Chagunda, 2011). In our model, when the duration of the inter-milking interval and the milking frequency were included in the sensitivity analysis, these factors were the dominant effects on both the milk drug concentrations and drug persistence.…”

Milking frequency and feeding level effects on feed intake, body condition score, energy balance, and feeding behavior of late lactation dairy goats

“…In early lactation cows, ODM management improved the nutritional status of the animals as they lost less live weight and body condition than those under TDM and thus improved their energy balance 8,9 . In late lactation cows in pasture-fed, ODM milking showed a minor effects on feed intake and body condition score gain 10 .…”