Smith J W, Adebowale E A, Ogundola F I, Taiwo A A, Akpavie S O, Larbi A, Jabbar M A
International Livestock Research Institute (ILRI), Addis Ababa, Ethiopia.
Trop Anim Health Prod. 2000 Oct;32(5):315-27. doi: 10.1023/a:1005269107863.
The aetiology of geophagia in periurban dairy cattle in Nigeria was assessed in relation to the mineral status of the serum, the herbage consumed, and the soil from where the herbage was consumed. The study was carried out using nine herds in the derived savannah zone during both the wet and dry seasons. Generally, the Na, Ca, Fe, Zn and Cu levels in the samples were adequate. However, the forages were low in Ca and the serum was deficient in P. Forage, soil and termite hill samples were also deficient in P. The low levels of P in the soil and termite hill samples showed that the consumption of sand by the cattle did not have any positive impact on their P intake. A seasonal effect was apparent (p < 0.05) on the serum Na+, PO4(3-), Cu2+ and Fe2+ concentrations but not on Ca2+ and Zn2+ concentrations. A seasonal effect was also significant (p < 0.05) on the minerals in the forage. There were also seasonal differences in most of the soil and termite hill minerals. Most samples had higher (p < 0.05) mineral levels in the dry season. Herd size and farming activity had no apparent influence on the aetiology of geophagia as they did not affect (p > 0.05) the concentration of P in the serum, the reported cause of geophagia. Geophagia is probably caused by a marginal level of P in the serum and low levels in the forage and soil. Experimental trials will be required to confirm these observations.
针对尼日利亚城郊奶牛群中食土癖的病因，研究了血清矿物质状况、所食用牧草以及牧草生长土壤之间的关系。研究在干湿两季选取了衍生稀树草原区的九个牛群展开。总体而言，样本中的钠、钙、铁、锌和铜含量充足。然而，牧草中的钙含量较低，血清中的磷含量不足。牧草、土壤和蚁丘样本中的磷含量也很低。土壤和蚁丘样本中磷含量低表明，牛食用沙子对其磷摄入量没有任何积极影响。血清钠、磷酸根、铜离子和亚铁离子浓度存在明显的季节效应（p < 0.05），但钙离子和锌离子浓度不存在季节效应。牧草中的矿物质也存在显著的季节效应（p < 0.05）。大多数土壤和蚁丘矿物质也存在季节差异。大多数样本在旱季的矿物质含量较高（p < 0.05）。牛群规模和养殖活动对食土癖的病因没有明显影响，因为它们不影响（p > 0.05）血清中磷的浓度，而血清磷浓度是食土癖的报告病因。食土癖可能是由血清中边缘水平的磷以及牧草和土壤中低水平的磷引起的。需要进行试验来证实这些观察结果。
