Woodfield D R, Easton H S
AgResearch Grasslands, Private Bag 11008, Palmerston North, New Zealand.
N Z Vet J. 2004 Dec;52(6):300-10. doi: 10.1080/00480169.2004.36446.
Plant breeding has had a substantial effect on the productivity and health of ruminant animals in New Zealand by improving the quantity, quality and reliability of grazed temperate pastures. Genetic changes have affected annual pasture productivity, seasonal growth, digestibility, protein/energy balance, level of rumen undegradable protein, leaf properties affecting intake, resistance to foliar diseases, and reductions in compounds that have an adverse impact on the health, welfare and reproductive fertility of ruminant animals. Most plant improvement programmes have achieved genetic gains in excess of 1% per year for a variety of target traits, and these gains are likely to continue given the high genetic variation available within forage plants. Significant heritable variation exists to improve forage quality, particularly for soluble carbohydrate and fibre fractions in grasses, and in the rate at which these change during the season. Deleterious animal health and welfare effects can be alleviated through the use of non-toxic endophytes in grasses, that do not produce lolitrem B and ergovaline. Use of improved cultivars, with the appropriate management, can add value to animal products.
通过提高温带放牧草场的数量、质量和可靠性，植物育种对新西兰反刍动物的生产力和健康产生了重大影响。基因变化影响了一年生草场生产力、季节性生长、消化率、蛋白质/能量平衡、瘤胃不可降解蛋白质水平、影响采食量的叶片特性、对叶部病害的抗性，以及减少了对反刍动物健康、福利和繁殖力有不利影响的化合物。大多数植物改良计划在各种目标性状上每年都实现了超过1%的遗传增益，鉴于饲草植物中存在的高遗传变异，这些增益可能会持续下去。存在显著的可遗传变异以改善饲草质量，特别是禾本科草类中的可溶性碳水化合物和纤维部分，以及这些成分在季节中的变化速率。通过在禾本科草类中使用不产生洛替米B和麦角缬氨酸的无毒内生菌，可以减轻对动物健康和福利的有害影响。使用改良品种并配合适当的管理，可以提高动物产品的价值。
