Balanced diets key to keeping cows in milk
Waikato dairy farmers are well-placed heading into the peak of summer, thanks to favourable growing conditions late last year that resulted in abundant onfarm feed reserves.
The first thing is to ensure quality ensiled is as high as possible, given the cost to make poor silage is much the same as good. “So maximise the quality going into the pit.”
With cereal silage in particular that can be tricky, he warned, as grain needs to be sufficiently mature to give the silage a good starch and hence energy content, but if cut too late the grains are too hard – unless crimped by the contractor – and pass straight through cattle undigested.
“The grain really is the engine of the crop.”
Pits need to be well stacked and compacted, and when feeding the aim is to maximise intake even if it means wasting a little in the process. “Intake is the key driver of growth rate,” he stressed.
Roughly the first 7kgDM/day of intake for a rising two-year-old cattle beast will be used for maintenance. Feed it 9kgDM/day and you might get 0.4-0.5kg of liveweight gain/day, but feed it 11-12kg and that will jump to 0.8-0.9kg liveweight gain/day.
“That’s a huge difference and it flows through to the cost you put on these animals.” Feed conversion to liveweight gain at the higher feed rate is a respectable 13:1. At the lower feed rate it’s 25:1 and infinite at maintenance.
With self-feed or feedlot systems the important thing is to ensure enough space for all animals to feed four or five times a day. Five Star works on one-third of a mob being able to feed at any one time. “Ideally you want to be able to get at least 25% upto the feed-face in one shot.”
Ensuring feed is always available during daylight hours, particularly at dawn and dusk when animals prefer to feed, is also important to maximise intake, said Gordon.
While the Giles’ limestone floored pits hadn’t had a problem self-feeding behind a wire, what can happen is cattle don’t eat down to the floor and the waste gradually builds up and up under their feet as they pull feed down and trample on it, he warned.
Five Star’s solution is to use purpose-made metal barriers so the feed falls down between them and the pit face, effectively forming a trough for the cattle to eat out of. When they can’t reach any more, the barrier’s pushed closer to the pit face again and more silage is pulled down.
Easy access to clean water is critical to achieving top performance, particularly with higher drymatter feeds.
“If they’ve got poor water or a long walk to get it, they won’t eat as much. It’s a bit like Weetbix: if you’ve not got enough milk you’re not going to eat many.”
Similarly, if cattle have to walk through “gumboot sucking” mud to get to feed, they’re not going to do it so often. “Studies have shown that once the mud gets over the hoof there’s a decrease in production.”
Minerals and vitamins also need to be considered, with deficiencies in the feed rectified with licks or minerals mixed into the stack at ensiling or feeding.
Certain feeds, such as maize, may need more protein adding for optimum stock growth rates. One way to do that is to add urea but Gordon stressed specialist advice should be sought as urea can be toxic if not incorporated properly.
“But the most important thing is to maximise feed intake. You can give animals all the minerals under the sun but if you’re not feeding them enough they’re not going to grow.”
