秋天出生的小牛在冬季的一年一度的料上爬行放牧
Gabriel J Pent1, William S Swecker2, Benjamin F Tracy3
1Shenandoah Valley Agricultural Research and Extension Center, Virginia Polytechnic Institute and State University, Raphine, VA 24472, USA.
Translational animal science
|July 1, 2025
概括
与旋转系统相比,爬行放牧的秋季小牛群改善了断奶重量,但需要更多的干草而没有改善重量,而不是连续放牧. 这项研究提供了关于优化小牛生产率和料管理的见解.
科学领域:
- 动物科学动物科学
- 飼料管理管理 飼料管理
- 牛肉牛生产 牛肉牛生产
背景情况:
- 在断奶前提高小牛的生产率对于肉牛作业至关重要.
- 爬行牧场系统使用高质量的料来补充小牛的营养.
- 不同的牧场养殖策略会影响料利用率和动物表现.
研究的目的:
- 为了比较爬行放牧系统 (CRP) 的生产率,与秋季生育牛群中多年性料的旋转 (ROT) 和连续 (CON) 养殖.
- 评估爬行牧场对小牛体重增加,身体状况得分和牛花草要求的影响.
主要方法:
- 秋季产牛群的管理是根据三个系统进行的:CRP (10%的冬季/夏季料牧场),ROT和CON多年料.
- 小牛在两周的断奶期前6~26天就能获得爬行料.
- 监测了爬行料的营养价值,奶牛的花草摄入量,奶牛的身体状况得分 (BCS) 和小牛的体重 (BW).
主要成果:
- 在CRP中,与CON (P=0.02) 相比,牛的花草需求更高.
- 在爬行放牧之前,牛的BCS在CON中较大 (P≤0.001).
- 奶时小牛的BW为CON和CRP (246公斤) 大于ROT (226公斤) (P≤0.002),CON和CRP之间没有差异.
- 从春天到断奶的小牛的平均每日增长 (ADG) 在治疗之间没有差异 (P≥0.41).
结论:
- 爬行放牧与凉爽季节的年料增强了秋天出生的小牛的断奶重量,而不是旋转养的多年生植物系统.
- 然而,爬行放牧系统需要增加干草补充量,但与连续养系统相比,不产生更高的断奶重量.
- 结果表明,需要仔细考虑料类型,系统管理和经济投入,以优化爬行动物放牧效益.
更多相关视频
相关概念视频
00:53Migration
8.1K
Migration is long-range, seasonal movement from one region or habitat to another. This common strategy, carried out by many different organisms around the world, is an adaptive response that typically corresponds to changes in an organism’s environment, like resource availability or climate. Migrations can involve huge groups of thousands of animals as well as single individuals traveling alone and can range from thousands of kilometers to just a few hundred meters.
8.1K
01:25Effects of Creep
223
Creep in concrete, the gradual deformation under prolonged stress, significantly impacts the integrity of structures. For reinforced concrete beams, it can be a vital design consideration, as it increases deflection, sometimes necessitating additional design measures. In columns, especially slender ones under eccentric loads, creep can cause buckling, compromising their stability. However, creep can be beneficial in indeterminate structures by mitigating stresses that arise from shrinkage,...
223
01:28Factors Affecting Creep
220
In normal-weight aggregate concrete, the hardened cement paste is the primary contributor to creep, whereas the aggregates, being stiffer than the cement paste, are more resilient to stress-induced deformation. The stiffness of the aggregates is defined by their modulus of elasticity, and the more voluminous they are in the concrete, the less it will creep.
Further, the water/cement ratio is critical, as a lower ratio increases concrete strength, thus reducing creep. The strength of the...
Further, the water/cement ratio is critical, as a lower ratio increases concrete strength, thus reducing creep. The strength of the...
220
00:51Energy Budgets
9.7K
Organisms must balance energy intake with the energy required for growth, maintenance and reproduction. These trade-offs result in a variety of survivorship and reproductive strategies, including semelparity and iteroparity. Semelparous species, like annual plants, have only one reproductive episode in their lifetimes and consequently have short lifespans. Iteroparous species, by contrast, have many reproductive events during their lifetimes but have relatively few offspring. These two...
9.7K
01:22Creep in Concrete
479
Creep refers to the time-dependent increase in strain under a sustained load, excluding other time-dependent deformations associated with shrinkage, swelling, and thermal expansion in concrete. The primary mechanism behind creep involves the loss of physically adsorbed water from the calcium silicate hydrate within the hydrated cement paste. This process is further exacerbated by concrete's non-linear stress-strain relationship, microcrack development in the interfacial transition zone, and...
479
01:57Adaptations that Reduce Water Loss
26.4K
Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and other cellular processes, evolutionary pressures on plants in different environments have driven the acquisition of adaptations that reduce water loss.
26.4K