Associations between milk production level, calving interval length, lactation curve parameters and economic results in Holstein cows

Abstract

The objective of work was to evaluate effects of milk production level (MY1≥9500 kg, n=23; MY2 = 8000-9499, n=28; and MY3≤7999 kg, n=29) and calving interval length (CI1≥440 days, n=22; CI2 = 400-439 days, n=33; and CI3≤399 days, n=25) on the lactation curve parameters calculated using MilkBot® Model and economic profitability of Holstein dairy cow breeding. Data were obtained from 80 Holstein cows on 1st to 4th parity calved between January and August 2012 on the dairy farm of the Czech University of Life Sciences Prague in Czech Republic. Lactation curve parameters differed more in relation with milk production level compared to calving interval length. Lactation curve in cows with the highest MY was characterized with significantly higher overall magnitude (scale parameter) of milk production (P<0.01), higher peak yield (P<0.01) which occurred later (P<0.05) and higher persistence (P<0.05). Due to combination of higher persistence and total yield, average milk yield per day of calving interval was significantly (P<0.05) higher in cows with middle CI than in short CI. Optimal calving interval length should be assessed in relation with lactation persistence and milk production level. The highest individual profitability was reached by cows in MY1 and CI2 group.

Analysis of milk production, age at first calving, calving interval and economic parameters in dairy cattle management

“…The group of longest CI (≥410 d) achieved the lowest net profit -0.85 CZK per L of milk, highest cow depreciation costs 0.85, and highest total costs 9.02 CZK per L of milk. Similar results found Němečková et al (2015) that long calving interval (≥440 days) resulted in a loss of 131.77 EUR. However, some studies do not agree with this and consider that the problem lies in inadequate management of high-producing herds, level of lactation persistency, and the genetic potential of animals (K adokawa and Martin, 2006).…”

Lactation curve modelling in dairy production

“…As it is generally known that the shape of lactation curve has a direct impact on both milk production and, consequently, milk revenue (e.g., Togashi and Lin, 2009;Němečková et al, 2015), AHE studies on reproduction management took into account the shape of the lactation curve, and thus included LCC in their decision support models. This approach provides opportunities for more informed decision making on reproductive decisions for individual cows.…”

“…As it is generally known that individual cows with a persistent milk production are more profitable (e.g., Dekkers et al, 1998;Němečková et al, 2015), it might be that herds with relatively more persistent cows are associated with higher profitability. Therefore, a herd lactation curve is needed to reflect the lactation curves of all individual cows in the herd.…”

“…Empirically, economic analyses have only included feed costs (Sölkner and Fuchs, 1987). Both normative and empirical studies have shown that cows with higher persistency are more profitable (e.g., Dekkers et al, 1998;Němečková et al, 2015).…”

“…To our knowledge, only Němečková et al (2015) have presented empirical economic evaluations of other lactation curve characteristics (ramp, scale) besides persistency.…”