Animal feed is the biggest cost for most cattle producers. In the United States, the cost of hay, grains and other feed has risen sharply because of a drought. At the same time, wildfires this year burned more than a million hectares of North American rangeland.
Jack Field raises cattle in the northwestern state of Washington. To save money, he made plans to truck his small herd of cows three hundred kilometers to feed on crop stubble. Crop stubble is what remains after crops have been harvested.
Moving his cattle from farm to farm costs money and time. But he says if he can avoid feeding them hay, he can still make a profit.
Tim DelCurto is a beef scientist at Oregon State University. He is working with ranchers and feedlot owners to help them find lower cost ways to feed cattle. He says cattle can eat things like grass-seed straw and distillers grains. These grains are left over from ethanol fuel production.
He says cattle can also eat cannery waste and items rejected by vegetable processors -- like misshapen green beans, carrots, even French fries.
"Now I think one of the unique attributes of beef cattle -- and sheep would fit this, too -- is that they can virtually digest anything."
The rising cost of feed has led agricultural research universities to give greater attention to what experts call "feed efficiency." The University of Idaho has a cattle barn where sensors measure exactly how much food each cow eats.
Professor Rod Hill says just because animals are growing at the same rate does not mean they eat the same amount of food. In fact the difference in how efficiently their bodies convert feed into meat, fat, bone and hide might be surprising.
"These animals are -- for your eye and mine -- they look quite homogenous. But the variation in intake for animals growing at the same rate is of the order of thirty-five percent."
This is a case where humans and animals have something in common.
"You know, we talk to people who say, 'All I have to do is, is, is look at the candy store and, and I put on three pounds.' We don't actually quantify it so precisely in humans, but we know in humans that some people can eat a little and they can put on quite a bit of weight and some people can eat a lot and hardly put on any weight. So it's a biological phenomenon."
Rod Hill says ranchers can use selective breeding to get the same growth with less feed. But he says not to focus too much on one thing, like reducing fat.
"Less-efficient animals are slightly fatter, and more-efficient animals are slightly leaner. So we wouldn't want to just go after efficiency and then forget about the body composition. So, we wouldn't want animals to become too lean, so that might reduce marbling in the product, especially in the quality cuts where the profit is."
雅思听力考试常用的四大技巧
雅思听力中的字母和图像缩写词
雅思听力场景分析:旅游场景
雅思听力高分备考攻略三步走
怎样做好雅思听力选择题的审题
雅思听力难题解析系列:地图题
纠正雅思发音及提高听力的方法
雅思听力场景词汇:全球地名篇
雅思听力场景词汇:饮料篇
雅思听力和国内英语考试的区别
雅思听力常考场景的单词短语分类
浅谈雅思听力语篇的衔接手段
雅思听力考试中的同义置换
雅思听力考场答题技巧:细心
雅思听力场景分析:预约医生
雅思听力六大陷阱需提高注意
雅思听力场景分析:租房篇
如何有效利用雅思听力考试时间
雅思听力场景词汇:职业名称
雅思听力场景词汇:生活类
雅思听力考试须知
雅思听力考试中的三大失分点
详解雅思听力信息表填空题
雅思听力的五个备考方法
雅思听力审题不能犯的四大错误
雅思听力地图题的解题技巧
雅思听力场景分析:选课场景
雅思听力场景解析:选课场景
雅思听力高分必备的三要素
冲刺阶段的雅思听力备考建议
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