There has been a marked change in the calving pattern on dairy farms in recent years. A substantial number of farmers are now targeting a 10- to 11-week breeding period. Many of these farms have also expanded cow numbers, leading to an intense breeding season. Added to this is a switch on some farms to 100% AI, with all of these factors combined putting pressure on handling facilities, particularly at the start of the breeding season.
While automatic drafting facilities are not eligible for grant aid, a batch AI crush is currently included for grant aid under the Targeted Agricultural Modernisation Scheme (TAMS II) and, as such, has detailed specifications for its construction.
The specifications are also useful for farmers installing a batch AI crush without grant aid but for the purpose of this article the recommendations on constructing a batch AI crush will be based on Department of Agriculture specification S137.
Batch AI crushes can be either fixed width or adjustable width to suit the size of cows on the farm. They must always be double-sided and not constructed against a wall. The crush should be designed in a manner which encourages cows to stand at an angle across the crush, similar to the way in which cows stand in a herringbone milking parlour.
The unit must include a rump rail, breast rail with neck and front and rear gates. The rump rail must be at least 1.28m in height and consist of at least three fixed rails and one drop rail.
The height of the three fixed rails should range from 440mm to 980mm above floor level. The top rail or drop rail should be fixed on hinges to allow it to be dropped out of the way quickly when cows are being artificially inseminated. While a top rail or drop rail is required under TAMS, some farmers opt not to include one.
The specifications state that rails should have an outside diameter (OD) of at least 48mm with a 3mm thick wall. Supporting uprights should be at least 60mm OD tubing with a 5mm thick wall positioned at centres of no more than 2m in distance or 80mm x 80mm x 4mm box steel at 2.3m centres.
The design of the breast rail includes a breast rail at least 810mm high with the underside of the neck rail supported at a height not exceeding 1.43m.
No vertical elements between the breast rail and the neck rail are permitted for the entire length of the batch crush barring an exception for one at the entrance end of the batch AI crush. This is a really important aspect as vertical rails will lead to the potential of animals getting their head caught as they move through the crush.
The breast rail must consist of at least two rails in a lattice form and be constructed with tubing of at least 60mm OD with a 3.0mm thick wall for adjustable width batch AI crushes.
While automatic drafting facilities are not eligible for grant aid, a batch AI crush is currently included for grant aid under the Targeted Agricultural Modernisation Scheme (TAMS II)
For fixed-width crushes the specification is at least two rails of minimum 48.0mm OD tubing with a 3mm thick wall.
The guideline for tubing for the neck is tubing of at least 90mm OD with this supported in a manner that ensure cows’ heads cannot be caught against the vertical elements.
The front and back gates should be plain, constructed at the same height as the rump side of the crush and angled to match the alignment of cows in the crush. The concrete floor of the unit must extend at least 1.2m out from the rump rail side of the crush.
The floor should be constructed to the same specification as that listed on pages 34 and 35.
The cost laid out for a batch AI crush under TAMS II is €210.10 per linear metre excluding VAT.
Pages 34 and 35 go into detail on designing cattle handling facilities. Under TAMS II it is permitted to install mass concrete footbaths in the race. Where installed, the specifications state that they shall be sized at a minimum of 2.5m long by the width of the race and 150mm deep.
The floor and the walls of the footbath must be at least 150mm thick concrete built on a hardcore base of at least 150mm as detailed in Figure 1.
There must also be a slope of one in five on entry and exit to the footbath to avoid step downs, which are highlighted as possibly stressing animals.
These ramps or sloped sections must also have a non-slip finish or horizontal grooves at 100mm intervals.
Foundations supporting steel uprights at the wall of the footbath must be 150mm deeper than advised on the previous pages for supporting standard uprights.
Proprietary, or specially made, footbaths are permitted to use as long as they possess certification by the manufacturer that they are suitable for cattle and have a minimum working life of 20 years. The Department advises such footbaths may require prior Departmental acceptance.