Feeding behavior preferences in livestock can be modified to implement a grazing management plan in woody crops. Here, we present a protocol to show a lithium chloride dose after eating a new plant that induces conditioned taste aversion.
Conditioned taste aversion (CTA) is a learning behavior process where animals are trained to reject certain feed after gastrointestinal discomfort has been produced. Lithium chloride (LiCl) is the preferred agent used in livestock to induce CTA because it specifically stimulates the vomit center. In addition, LiCl is commercially available, and easy to prepare and administer using a drenching gun. Nevertheless, some factors have to be considered to obtain an effective long-lasting CTA, which allows small ruminants to graze during the cropping season. A key aspect is to use animals with no previous contact with the target plant (the plant chosen to be avoided; new feed). Due to their native neophobic feeding behavior, small ruminants can easily associate the negative feedback effects with the new feed, resulting in a strong and persistent CTA. The recommended doses are 200 and 225 mg LiCl/kg body weight (BW) for goats and sheep, respectively. To induce CTA, 100 g of the target plant should be individually offered for at least 30 min, and LiCl administered thereafter if the intake is greater than 10 g. Each time the animal eats the target plant without negative consequences, the CTA becomes weaker. Consequently, to minimize the risk of target plant consumption, it is essential to have sufficient palatable ground cover available. The presence of an alternative feed (of quality and quantity) prevents the accidental consumption of the target plant. A close monitoring of the flock is recommended to remove and re-dose any animal consuming more than 4 bites or 10 g of the target plant. At the beginning of each grazing season, check the CTA status of each animal before moving them to the crop.
利用木本作物行间地面覆盖减轻土壤侵蚀和退化,增加水,有机碳和氮潴留1-3。此外,地面覆盖保持和增加生物多样性,支持农作物害虫及其天敌之间的平衡。农民往往以消除农化应用产品或使用收割机机杂草;从而减少农作物和绿化覆盖率之间的竞争养分。以控制地面覆盖一个经济有效的方法是使用小反刍动物放牧。从动物放牧一个额外的好处是在土壤中的健康和生育的改善。然而,农民是不愿意实施这种做法,由于小反刍动物通过消耗嫩叶和豆芽损坏庄稼。
为避免可能对作物的损害是非常有用的诱导羊群或畜群内的绵羊或山羊条件味觉厌恶(CTA)。该CTA很容易对n成立EW饲料,由于小反刍动物的先天饲料恐新症行为4,5,和因为熟悉进料正与一个相关的“学习安全”状态这是更难以改变或操纵6。动物学会拒绝特定的饲料(条件刺激),由于其负后摄食效应(无条件刺激)。以诱导CTA朝适口和无毒的植物,氯化锂(氯化锂;电感剂)动物消耗的靶植物后口服给药。虽然有其他电感剂( 例如阿朴吗啡,ciclosphosphamide,噻菌灵),氯化锂显示出最强和最持久的CTA由于由化学感受器触发区面积的刺激和胃肠道不适7,8与一般轻微迹象其催吐系统的影响不适。锂(Li)从上胃肠道吸收和分布于全身水空间9。动物CAn具有恢复期短两天7,10,11。
的氯化锂可以通过与食物12,13混合它,在明胶胶囊13,14或在由浸透枪15-17口服溶液给药。虽然氯化锂的解决方案是刻薄的,在口腔或食管没有受伤被描述。氯化锂是在100至400毫克的LiCl / kg体重(BW)的范围内使用,在使用较高剂量16,18更好的结果(更持久CTA)。尽管如此,考虑到对不同物种和品种的已知剂量的影响,在某些情况下的致死效果开始于400毫克的LiCl / kg体重。一个有效的长期推荐剂量CTA开始在200毫克/公斤体重山羊和225毫克/千克体重的羊10,17,19。李用在这些剂量第4天给药后内排出,主要通过尿(92±4%),其次为粪便(6.5±1.3%)和乳(2.8±0.4%)11。完整估计停药期为氯化锂的血浆中的单剂量为9和11天的绵羊和山羊,分别。由于牛奶中的最小的李排泄,CTA不能自然建立的哺乳断开弹簧11,20。
绵羊长期持久CTA已报道一整个放牧季节(3-4个月)时的替代饲料来源是提供14,21,下一个牧场被重新建立与单一的LiCl剂量几乎完全规避旺季(9月以后)14。此外,2年和3年的CTA不放过已经报道了在牧草条件下牛,而不需要加强剂量,当目标进料是一种有毒的,但适口植物22,23。考虑的替代原料的选择是至关重要的动物保持CTA对无毒的植物。每次动物消耗超过10克避免植物的,而不会导致胃肠二scomfort,注册税务师将受到影响24。
该CTA是很容易成立于小反刍动物,如果目标饲料是动物从来没有吃过,不包含着不可替代的营养物质的植物。动物与非毒性饲料的正后的摄食关联除非前一次的接触使得难以改变其特定进料7,33的感知。条件味觉厌恶产生的LiCl因为生产刺激感觉不舒服或胃肠不适34催吐系统。已确定,动物消耗的LiCl增加呼吸率,显示出头部和耳下垂,他们偶尔会踢自己在胃25中 ,并显示牛?…
The authors have nothing to disclose.
This work is part of a CICYT research project (AGL 2010-22178) of the Spanish Ministry of Science and Technology. The authors are grateful to Nic Aldam and Kristi Prunty for the English revision of the manuscript.
Lithium Chloride PRS | Panreac | 141392.1209 | Different amounts of same product can be supplied by the same company. |
Labelvage drencher 70 mL | Labelvage | 240040 | Similar product can be used (different brand or volume). |