Pathology and Haemato-biochemical changes and Economic impact in Goats feeding on Opuntia Stricta and Community Perception of the Plant in Laikipia County, Kenya

Abstract

Opuntia stricta variety stricta (O. stricta), a plant with thorns and spines has invaded northern part of Laikipia County, Kenya and reduced prime grazing land and pastures. Its cladodes (the green flat paddle-shaped stem segments) and fruits are protected by thorns and small spines called glochids. This study was carried out in Laikipia North Sub-county, Laikipia County between October 2018 and February 2019. The objectives were to determine haemato-biochemical changes and pathology and economic impacts in goats consuming O. stricta and the community perception of the plant and its risk factors. A semi-structured questionnaire was used to determine knowledge, attitude and practices and risk factors associated with O. stricta. Most of farmers knew O. stricta as “Olmatundai” in Maasai language and had lived with it for the last sixty years. Respondents specified that O. stricta grows in both dry and rainy seasons and that goat mainly feeds on its fruits. Farmers know that the plant causes emaciation, deaths, blindness, injuries on the lips and mouth, skin and muscles. They observed that proliferation of O. stricta in the area has displaced people, decreased the grazing land, limited peoples’ movements from their residences, increased human-wildlife conflicts and impoverished them through mortalities of livestock. Eighteen (18) goats whose health was affected by feeding on the plant (sick goats) were purchased from three locations that were invaded by this cactus. Six goats that were clinically healthy (controls) were purchased from two O. stricta free ranches in the study area. Blood samples for haematology and biochemistry were taken from the two groups and analyzed. Animals were humanely killed and postmortem examination conducted. Goats that had progressively fed on O. stricta had the following external lesions: thorn and spine injury-associated blindness (38.9%); septic ulcerative wounds on the lips and mouth (94.4%) or tongue (83.3%); Opuntia stricta spines and thorns piercing the ear lobes and various parts of the skin (100%); abscesses at various locations (22.2%); emaciation (100%) that led to death. Internally, O. stricta thorns and spines were embedded on the subcutaneous tissues, muscles, rumen, reticulum and abomasum mucosa. Mucosa of abomasum had thick folds; edema and hemorrhage, and in some cases severe septic abscesses; and foreign body granulomas in the tunica mucosa and tunica submucosa. Foreign body granulomas occurred in the ears, lips and tongue. Affected goats had microcytic regenerative anemia that was associated with iron deficiency; neutrophilia and lymphopenia that are consistent with severe inflammation. Low levels of albumin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen and creatinine occurred in all goats that were affected by the plant. Low carcass and organ weights, and reduced muscle and fat cover occurred in all sick goats. Focal inflammation and necrosis of skeletal and smooth muscles that occurred in sick goats happened consistently with increased levels of creatine kinase in plasma. Emaciation of the sick goats was attributed to malnutrition caused by reduced feed intake due to severe injuries by O. stricta spines in the gastrointestinal tract. The occasioned death of livestock and loss of body weight (emaciation) as a result of consumption of the O. stricta caused enormous economic losses to pastoral communities in the study area. Costs of treatment of O. stricta related conditions, frequent condemnations of whole carcasses and organs added to the losses. Consumption of O. stricta caused severe irreversible damage to gastrointestinal system especially the oral cavity and abomasum. Injuries to organs reflected on alterations in blood parameters of goats. The study showed that no treatment or intervention measures can reverse the damage caused by many thorns and spines penetrating into body systems of goats consuming O. stricta. Measures to control this invasive plant in Laikipia north should be instituted in order to minimize losses in livestock production and the associated impacts on lives and livelihoods of the people in the area.