The Effect of Pasture Allowance and Supplementation on Feed Efficiency and Profitability of Dairy Systems

Abstract

Partial budgeting was used to compare income over feed costs of high-yielding Holstein cows based on data from an experiment with 4 dietary treatments arranged in a 2 x 2 factorial. The factors were low (25 kg DM/cow per day) and high (40 kg DM/cow per day) pasture allowance (PA) and supplemental grain fed at 1 kg/4 kg of milk or no supplemental grain fed. The 4 treatments were low PA unsupplemented (LPAU), low PA concentrate supplementation (LPAC), high PA unsupplemented (HPAU), and high PA concentrate supplementation (HPAC). Two management systems were modeled. The first, a fixed herd size flexible rotation length model, and the second, a flexible herd size model where rotation length was fixed. The LPAC treatment yielded the highest income over feed costs, followed by the HPAC treatment. The treatment generating the lowest income was the HPAU system. The low PA systems generated more income than did the high PA systems for equivalent supplemental feeding strategies. The results also showed that feeding supplemental grain increased the income-over-feed costs compared with systems that did not feed supplemental grain. In most treatments, comparing the fixed herd against the flexible herd models, the flexible herd size model generated higher income due to the substitution of relatively low income per hectare of hay production for higher income from milk production. There were also differences in feed conversion efficiencies for milk production due to concentrate supplementation (1.04 unsupplemented vs. 1.21 supplemented), but PA did not affect the efficiency of milk production. Neither supplementation nor PA affected the feed conversion efficiency of milk fat yield. However, the efficiency of milk protein yield was affected by concentrate supplementation (0.028 unsupplemented vs. 0.034 supplemented) but not by pasture allowance.

Pasture‐based dairy farm systems increasing milk production through stocking rate or milk yield per cow: pasture and animal responses

“…Thus, lower intakes at the higher stocking rates were avoided, removing one of the main causes of poor FCE in pasture‐based systems (Beever and Doyle, 2007; Kolver, 2007). These results are in line with those by Tozer et al. (2004) who also found no effect of increasing stocking rate on FCE working with high genetic merit cows on supplemented pasture‐based systems.…”

“…, 2009) proposed that with improved feeding management (i.e. including supplementation when pasture availability is limiting), farmers could avoid reductions in feed intake and milk yield per cow and therefore in FCE (Tozer et al. , 2004).…”

Some challenges and opportunities for grazing dairy cows on temperate pastures

“…Efficiency of supplementation depends on the relative costs of grazing and supplement, grazed herbage allowance, season and stage of lactation (Tozer, Bargo, & Muller, 2004). Although herbage DMI is reduced, total DMI is increased and the reduction in total N intake is inversely related to substitution rate.…”

Energy balance, milk production and reproduction in grazing crossbred cows in the tropics with and without cereal supplementation

“…Calculating the income over feed costs, Tozer et al (2004) found a better performance in Supplemented cows ($4.51 vs. $3.30/cow/day). Numerous studies have examined production responses to concentrates in cows of medium or high milk potential consuming tropical forages, but reproductive variables have not been reported (Combellas, 1998).…”