grazing

Bijeenkomst: EGF2015
Auteur: Hennessy D., Delaby L., Van den Pol-van Dasselaar A. and Shalloo L.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
In temperate and oceanic regions, grazed grass is the lowest cost feed available for milk production. In other regions, grazed grass is less important but can contribute to the diet of livestock. Within high output systems the interaction between the animal and sward is challenging for a host of reasons, including intake and milk production potential, substitution, grass allowance, quality, etc., which often means that grass utilisation and quality are compromised. Adaptation of grazing management and implementation of a range of grazing strategies can provide possibilities to increase the proportion of grazed grass in the diet of dairy cows in high output systems. As Europe transitions to a non-milk quota situation, increasing scale, or herd size, will probably lead to a trend towards a reduction in grazing, and may lead to a loss of the benefits of grazing. Therefore, strategies are required to increase the level of grazed grass in the diet of dairy cows on high output farms through the integration of grassland measurement and budgeting within everyday grassland management practices. There is a growing body of literature describing the benefits of grazing from an economic, environmental, animal welfare and overall social dimension. However, there are fewer reviews highlighting the constraints and difficulties to maintaining a high level of grass utilisation and good grazing performance in high output systems. The objective of this review is to present a balanced overview of the possibilities and the constraints for grazing in dairy systems in the future.

Bijeenkomst: EGF2015
Auteur: Bélanger G., Tremblay G.F., Dos Passos Bernardes A., Papadopoulos Y., Fillmore S., Lajeunesse J. and Duynisveld J.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
Legume-grass mixtures generally provide more consistent forage yield than monocultures. We studied 18 binary mixtures of one legume and one grass species for dry matter (DM) yield, neutral detergent fibre (NDF) concentration and in vitro digestibility (NDFD), and estimated milk production per hectare. Cocksfoot (Dactylis glomerata L.), Kentucky bluegrass (Poa pratensis L.), meadow bromegrass (Bromus biebersteinii Roemer & J.A. Schultes), meadow fescue (Festuca elatior L.), tall fescue [Schedonorus phoenix (Scop.) Holub], and timothy (Phleum pratense L.) were seeded with birdsfoot trefoil (Lotus corniculatus L.), lucerne (Medicago sativa L.) or white clover (Trifolium repens L.). Frequent clipping at two sites, simulating grazing, and cattle grazing at one site were imposed on the 18 binary mixtures in this 3-year study conducted in eastern Canada. Legume and grass species significantly affected seasonal herbage DM yield, NDF concentration, and NDFD of the mixtures averaged over three production years. Birdsfoot trefoil in mixtures with meadow bromegrass or timothy resulted in the largest estimated milk production per hectare under frequent clipping, whereas white clover with meadow bromegrass or tall fescue provided the best results under cattle grazing. Frequent clipping and cattle grazing affected differently the performance of the mixtures, primarily for the legume component. Meadow bromegrass performed very well with the three legume species and under both frequent clipping and cattle grazing.

Bijeenkomst: EGF2015
Auteur: Cornelissen J.M.R., De Haan M.H.A., Hin C.J.A., Zijerveld E.J.M. and Philipsen A.P.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
The Dutch dairy sector is leading in production efficiency with research and innovation achieving great improvements by focussing on the cow as the central production factor. Grass and soil, while also being essential production factors, have received much less attention. Recent developments mark a turning point for attention to grass production and grazing. While increased focus on grass production and grazing is generally considered as sustainable development, it is centred around the dimensions of people or planet; the profit dimension is under-represented. This paper builds the economic case for an increased focus on grass production and grazing by modelling the exploitable yield of grass production in the Netherlands. The current dry matter (DM) production is assessed at 6.0×106 Mg. The potential production is modelled at 9.3×106 Mg, thus leading to an exploitable net yield of 3.3×106 Mg. This is over 1.5 times the current grass production. Financially, the additional production implies a gain of 500 million euros when taking into account the market price for grass DM. When considering the feed value profits may rise to 750 million euros.

Bijeenkomst: EGF2015
Auteur: Holshof G., Evers A.G., De Haan M.H.A. and Galama P.G.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
Dairy herds in the Netherlands will increase in size in the coming years, due to the imminent abolition of milk quotas. Also more farms will make use of automatic milking systems (AMS). Both trends mean less opportunity for grazing. As the grazing area itself will not increase it has become a priority to explore new ways of grazing. At Dairy Campus – a Dutch experimental farm – two distinct grazing systems were tested: strip grazing with AMS and one-day rotational grazing with a fixed paddock area and a standard growing period of 23 days. The grazing time was restricted to daytime. At night the cows were fed silage and concentrates. In the one-day rotational grazing, the grass allowance depended on what was grown in 23 days on the fixed paddock. The silage feeding was adapted to the allowed amount of grass. The total allowance of grass and roughage for both systems was 16 kg dry matter cow‑1 d‑1 supplemented with concentrates. The strip grazing system had a fixed allowance of 8 kg DM grass cow‑1 d‑1 supplemented with 8 kg TMR cow‑1 d‑1. Model calculations showed a relation between grazing efficiency, milk price and income. Grazing will be more profitable than an indoor system at lower milk prices. At higher milk prices a high grazing efficiency is necessary to make a grazing system profitable.

Bijeenkomst: EGF2015
Auteur: McCarthy B., Dineen M., Guy C., Coughlan F. and Gilliland T.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
An experiment to investigate the impact of tetraploid and diploid perennial ryegrass swards sown with and without white clover on the productivity of spring milk production systems was established in 2012 (75%) and 2013 (25%). Four separate grazing treatments/swards were sown for the experiment: tetraploid only, diploid only, tetraploid with clover and diploid with clover. Eight cultivars (four diploid: Tyrella, Aberchoice, Glenveagh and Drumbo; four tetraploid: Aston Energy, Kintyre, Twymax and Dunluce) were sown as monocultures with and without clover. Thirty cows were allocated to each treatment after calving in February 2014. All treatments were stocked at 2.75 cows ha‑1 and received 250 kg of nitrogen fertiliser ha‑1. There was no difference in milk or milk solids yield between the tetraploid-only (4,895 and 414 kg cow‑1, respectively) and diploid-only (4,848 and 403 kg cow‑1, respectively) swards. However, incorporating clover resulted in 13.3% greater milk yield and 13.4% greater milk solids yield (5,532 and 464 kg cow‑1, respectively, and 5,506 and 462 kg cow‑1, respectively, for the tetraploid with clover and diploid with clover treatments, respectively). Pasture dry matter (DM) production was 16.8% greater on the grass-clover swards (17,400 kg DM ha‑1) compared to the grass-only swards (14,900 kg DM ha‑1).

Bijeenkomst: EGF2015
Auteur: Foley C., Shortall J. and O’Brien B.
ISBN: 978-9090-289-61-8
Jaar van uitgifte: 2015
Producttype: Paper
Voluntary movement of cows from paddock to milking yard is an inherent aspect of an automatic milking system (AMS) integrated with grazing. The motivation for the cow to present at the milking yard, during the main grass-growing period, is the trained knowledge that they will be rewarded with fresh grass in a new paddock. In late-lactation concentrate supplementation assists in ensuring the cow receives adequate nutrition. Although the cow decides to present at the milking yard, AMS settings determine when the cow is milked based on milk yield and time since last milking. The aim of this study was to investigate the influence of milking permission and concentrate supplementation on milk production and cow traffic. There were 4 treatments with combinations of milking permissions, 3.2 or 1.8 times per day and concentrate supplementation allowance of either 3 kg or 0.84 kg per day. This study has highlighted strategies to maintain consistent milk production and cow traffic in the latter stages of lactation, through adjusting AMS settings for concentration supplementation and milking permission.