Supplementing Pasture to Lactating Holsteins Fed a Total Mixed Ration Diet

Abstract

Beginning in September 1997, a 6-week study was conducted to compare performance and income-over-feed cost of lactating Holsteins cows fed either a total mixed ration diet (TMR) only, compared to TMR in the afternoon and pasture in the morning, or TMR in the morning and pasture in the afternoon. Fifty-four Holstein cows in midlactation, averaging 28.1 kg/d of milk, were used in the study. Cows were on pasture for 8 h/d after either the p.m. or the a.m. milking. Predominantly orchardgrass with lesser amounts of white clover and Kentucky bluegrass were grazed. Pasture was sampled once per week, and weekly composites were analyzed. Compressed sward height and herbage dry matter (DM) yield were estimated once per week. Milk yield was electronically recorded and was sampled biweekly. Body condition score and body weight (BW) was recorded at the beginning and end of the study. Income-over-feed cost was calculated for each treatment. Compressed sward height and DM yield averaged 12.7 cm and 1397 kg/ha, respectively. Pasture crude protein, neutral detergent fiber, and acid detergent fiber averaged 27.0, 55.7, and 26.9%, respectively, and net energy-lactation was 1.65 Mcal/kg of dry matter. Milk production was greater for cows on the TMR treatment (29.1 vs. 28.2 and 27.6). No significant difference occurred in percentage of milk fat (3.54, 3.42, and 3.46%), or protein (3.28, 3.20, and 3.22%) for the above respective treatments. The SNF content (8.77 vs. 8.67 and 8.63%) was higher in TMR cows. While BW change did not differ among treatments (23, 32, and 22 kg), body condition score change was greater in cows fed TMR only (0.14 vs. -0.06 and 0.01). As expected, TMR intake was greatest for cows fed TMR only and lowest for cows grazing after the p.m. milking (26.6 vs. 20.3 vs. 17.5 kg/d dry matter). Income-over-feed cost differed between treatments and was approximately 18.6 and 7.5% higher for cows grazing high quality pasture during the afternoon and the morning, respectively, compared with cows on the TMR treatment.

Modeling milk urea of Walloon dairy cows in management perspectives

“…The same trend with higher MU during the summer months (July to September) has been reported by several authors (Godden et al, 2001;Rajala-Schultz and Saville, 2003;Wattiaux et al, 2005). This fluctuation could reflect the grazing period and the access of cows to fresh pasture, which typically contains highly degradable protein and has a high protein-to-energy ratio (Soriano et al, 2001). Moreover, this seasonal effect varied from year to year; the MU level increased slightly across years.…”

The effect of grazing on the composition of conjugated linoleic acid isomers and other fatty acids of milk and cheese in goats

“…Soriano et al (2001) in Holstein cows and Soryal et al (2004) in Alpine goat also found that pasture feeding slightly increased the milk fat, protein and solid without fat contents and decreased the lactose content. These results suggested that the milk produced by the grazed group would have a higher cheese yield.…”

Overnight access to pasture does not reduce milk production or feed intake in dairy cattle

“…Previous studies that compared cows housed indoors and continuously on pasture reported lower BW, milk production and milk protein in the case of grazing cows (HernandezMendo et al, 2007;Kolver and Muller, 1998). Soriano et al (2001) reported that cows kept on pasture 8 h/day after either the morning or afternoon milking consumed less TMR compared to when they were indoors, and produced less milk than cows kept indoors. In contrast, the cows in our study were able to consume TMR during the daylight hours, when they are highly motivated to eat (DeVries et al, 2003), and thus were able to maintain similar intakes to those cows housed indoors continuously.…”

“…Even with ideal pasture conditions, the lower nutrient density of grass relative to more concentrated feeds provided indoors will likely reduce milk production for pasture-housed animals (Soriano et al, 2001). Previous work in our group has shown indoor group housed dairy cows consume more than 80% of their daily DMI from 0700 to 2000 h (Huzzey et al, 2007) and that when provided free access to pasture, they normally choose to stay indoors during the day and move outdoors to pasture at night (Legrand et al, 2009).…”