White S L, Benson G A, Washburn S P, Green J T
Department of Animal Science, North Carolina State University, Raleigh 27695, USA.
J Dairy Sci. 2002 Jan;85(1):95-104. doi: 10.3168/jds.S0022-0302(02)74057-5.
This 4-yr study examined total lactation performance of dairy cows in two feeding systems: pasture-based and confinement. Spring and fall calving herds were used and each seasonal herd had 36 cows on pasture and 36 cows in confinement with 282 Holstein and 222 Jersey cows included over seven seasonal replicates. Pasture-fed cows received variable amounts of grain and baled haylage depending upon pasture availability. Confinement cows received a total mixed ration with corn silage as the primary forage. Data were collected on milk production, feed costs, and other costs. Pasture-fed cows produced 11.1% less milk than confinement cows. Across treatments, Jerseys produced 23.3% less milk than Holsteins, but calving season and various interactions were not significant. Feed costs averaged $0.95/cow per day lower for pastured cows than confinement cows. Feed costs were lower for Jerseys than Holsteins and for cows calving in spring. Income over feed costs averaged $7.05 +/- 0.34 for confinement Holsteins, $6.89 +/- 0.34 for pastured Holsteins, $5.68 +/- 0.34 for confinement Jerseys, and $5.36 +/- 0.34 for pastured Jerseys; effects of breed were significant but treatment, season, and interactions were not. Economic factors such as labor for animal care, manure handling, forage management, and cow culling rates favored pastured cows. Higher fertility and lower mastitis among Jerseys partially offsets lower income over feed cost compared with Holsteins. Milk production was lower in this study for pasture-based systems but lower feed costs, lower culling costs, and other economic factors indicate that pasture-based systems can be competitive with confinement systems.
这项为期4年的研究考察了奶牛在两种饲养系统中的总泌乳性能:以牧场为基础的饲养系统和圈养系统。使用了春季和秋季产犊的牛群,每个季节的牛群中有36头奶牛在牧场饲养,36头奶牛圈养,在7个季节的重复试验中,共有282头荷斯坦奶牛和222头泽西奶牛。以牧场为食的奶牛根据牧场的可利用情况,会获得不同数量的谷物和打包青贮饲料。圈养的奶牛则食用以玉米青贮为主要草料的全混合日粮。收集了牛奶产量、饲料成本和其他成本的数据。以牧场为食的奶牛产奶量比圈养奶牛少11.1%。在所有处理中,泽西奶牛的产奶量比荷斯坦奶牛少23.3%,但产犊季节和各种交互作用不显著。以牧场为食的奶牛的饲料成本平均比圈养奶牛每天低0.95美元/头。泽西奶牛的饲料成本低于荷斯坦奶牛,春季产犊的奶牛饲料成本也较低。圈养的荷斯坦奶牛饲料成本之上的收入平均为7.05±0.34美元,牧场饲养的荷斯坦奶牛为6.89±0.34美元,圈养的泽西奶牛为5.68±0.34美元,牧场饲养的泽西奶牛为5.36±0.34美元;品种的影响显著,但处理、季节和交互作用不显著。诸如动物护理、粪便处理、草料管理和奶牛淘汰率等经济因素有利于牧场饲养的奶牛。与荷斯坦奶牛相比,泽西奶牛较高的繁殖力和较低的乳腺炎发病率部分抵消了饲料成本之上较低的收入。在本研究中,以牧场为基础的饲养系统的牛奶产量较低,但较低的饲料成本、较低的淘汰成本和其他经济因素表明,以牧场为基础的饲养系统可以与圈养系统竞争。