The Effect of Herbage Allowance and Concentrate Supplementation on Milk Production Performance and Dry Matter Intake of Spring-Calving Dairy Cows in Early Lactation

Abstract

The objective of this study was to determine the effect of daily herbage allowance (DHA) and concentrate level on milk production and dry matter intake of spring-calving dairy cows in early lactation. Seventy-two Holstein-Friesian dairy cows (mean calving date February 2) were randomly assigned across 6 treatments (n = 12) in a 2 x 3 factorial arrangement. The 6 treatments consisted of 2 DHA ( > 4 cm) and 3 concentrate levels: 13 kg of herbage dry matter/cow per d (low) or 17 kg of herbage dry matter/cow per d (high) DHA and unsupplemented, 3 kg, or 6 kg of dry matter concentrate/cow per d. The experimental period (period I) lasted 77 d and was followed by a carryover period (period II) during which animals were randomly reassigned across 2 grazing treatments offering 17 or 21 kg of herbage dry matter/cow per d. Increasing DHA significantly increased milk (+1.85 kg), solids-corrected milk, protein (+79.5 g), and lactose yields, protein concentration, and mean body weight (BW). Mean body condition score (BCS) and end-point BCS were also significantly higher with the high-DHA treatments. There was a linear response in milk yield, milk lactose concentration, and solids-corrected milk to concentrate supplementation. There was a significant difference in mean BW as concentrate increased from 0 to 3 kg (506 and 524 kg, respectively); there was no further increase in BW when 6 kg of concentrate was offered. Cows offered the low DHA had significantly lower grass dry matter intake (13.3 kg) and total dry matter intake (16.3 kg) than the high-DHA cows during period I. Concentrate supplementation significantly increased total dry matter intake. During period II, previous DHA continued to have a significant carryover effect on milk protein concentration, BW change, mean BCS, and end-point BCS. Concentrate supplementation during period I continued to have a significant carryover effect in period II on milk yield; milk fat, protein, and lactose yields; solids-corrected milk yield; BW; and mean BCS. Results from this study indicate that offering a medium level of DHA (17 kg of herbage dry matter) in early lactation will increase milk production. Offering concentrate will result in a linear increase in milk production. In an early spring feed-budgeting scenario, when grass supply is in deficit, offering 3 kg of dry matter concentrate with 17 kg of DHA has the additive effect of maintaining the grazing rotation at the target length as well as ensuring the herd is adequately fed.

Using post-grazing sward height to impose dietary restrictions of varying duration in early lactation: its effects on spring-calving dairy cow production

“…This deficit in energy intake was reflected in the high response (3.50 kg milk/cm increase in PGSH) to any additional herbage offered to the M cows, through an increase in PGSH. This response is higher than that reported by Ganche et al (2013a;2.88 kg of milk per extra centimeter in PGSH) and McEvoy et al, (2008;2.11 kg milk per extra centimeter in PGSH), and indicates how restrictive the feed allowance offered to the S cows actually was. Mobilisation of body energy reserves, leading to a decline in BCS postpartum, is generally used to bridge the energy deficit gap (Roche et al, 2006;McCarthy et al, 2007).…”

“…Roche (2007) and McEvoy et al (2008) disagree, as both found that an inadequate level of feed in early lactation reduced subsequent milk production; however, in both experiments, the range of PGSH was much larger, 3.1 or 3.5 to 5.0 cm, respectively. Again, these experiments reported much larger differences in milk production than in the present experiment, which had a comparatively smaller difference between treatments.…”

“…Maintaining a constant PGSH (Ganche et al, 2013b) rather than imposing a restrictive daily herbage allowance (DHA), which allows PGSH to fluctuate (Friggens et al, 1998;Wales et al, 1998;McEvoy et al, 2008), ensures that sward utilisation is maximised (Ganche et al, 2013b). However, Lee et al (2008) reported decreased grass production with extreme defoliation heights of 2 cm.…”

Development and evaluation of the herd dynamic milk model with focus on the individual cow component

“…This compares with 0.02 to 0.23 kg of milk/kg of HA in the literature. As shown in previous studies, the concentrate response increased with the theoretical milk production (Fulkerson et al, 2008) and it decreased with increasing HA (McEvoy et al, 2008). The outcomes from this model are within the range of the previously published studies for concentrate supplementation (Supplementary Table S5) with the impact of 1 kg of concentrate resulting in an increase of 0.5 to 1.1 kg of standard milk across different genotypes and HA categories.…”

Merging and characterising phenotypic data on conventional and rare traits from dairy cattle experimental resources in three countries

“…Data were collated from several studies that had been previously conducted (Buckley et al, 2000;Kennedy et al, 2003;O'Donovan and Delaby, 2005;Horan et al, 2006;Kennedy et al, 2006;McCarthy et al, 2007;McEvoy et al, 2007). In brief, these studies compared either alternative genotypes of Holstein-Friesian cows raised on different production systems or alternative grazing strategies or grass varieties.…”