The antibacterial activity of some medicinal plants used in Meru Central District, Kenya

Five medicinal plants used by traditional medical health practitioners (TMP) in Meru central district namely: Piliostigma thonningii, Ajuga remota, Ocimum suave, Erythrina abyssinica and Harissonia abyssinica were investigated for their antibacterial activity against standard bacterial cultures namely; Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. The antibacterial activity of the methanolic and water extracts was determined using the minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC). Gram positive bacteria (S. aureus and B. cereus) were more susceptible to the plant extracts than Gram negative bacteria (E. coli and P. aeruginosa). The MIC and MBC of the positive control antibiotics (Ampicillin for gram positive and Gentamycin for gram negative) were less than 1mg/ml. The most susceptible bacteria was S. aureus followed by B. cereus while the most resistant was E. coli followed by P.aeruginosa. Methanolic extracts of P. thonningii stem and Ocimum suave leaves had the best antibacterial activity against the four bacterial species. There was no significant difference between the water and methanolic extracts of all the plants. These results justify the use of these plants by the traditional medical practitioners for management of bacterial conditions and further investigation on their safety and phytochemistry is needed

Co-administration of Albendazole and Levamisole to control multiple anthelmintic resistant nematodes in a sheep farm in Kabete Kenya

Albendazole (ABZ) and levamisole (LEV) were co-administered to evaluate their ability to control natural helminth infections in a sheep farm where resistance to the individual anthelmintic had previously been reported. Thirty two sheep of mixed ages and sex were randomly allocated to four equal groups. Group 1 and 2 were treated with ABZ and LEV respectively. ABZ and LEV were co-administered to group 3 while group 4 was the untreated control. Rectal faecal samples were collected from all the animals on the day of treatment (0 DPT) and fourteen days post-treatment (14 DPT) and the eggs per gram of faeces (EPG) determined. On both sampling occasions, pooled feacal samples from the respective groups were separately cultured for strongyle larval stage three (L3) identifications. Anthelmintic efficacies were evaluated based on faecal egg count reduction percentage (FECR%). Resistance to both drugs was still evident at FECR% of 71% and 75% for LEV and ABZ respectively. Co-administration of the two drugs resulted in a higher efficacy at 95.4% FECR %. L3 recovered from faecal culture 14DPT indicated that Haemonchus spp. survived treatments with ABZ and LEV given separately and when co-administered. Trichostrongylus spp. survived the LEV treatment but was highly susceptible to ABZ given alone or when co-administered with LEV, while Oesophagostomum species survived ABZ given separately. Combining these two drugs may therefore offer a temporary solution in helminth control on the farm as other control measures are sort.Key words: Efficacy, resistance, albendazole, levamisole, co-administratio

Research Articles: Pharmacology and Toxicology Acute toxicity of Nicandra physaloides (L) Gaertn in Cattle and Mice

Nicandra physaloides (L) Gaertn (Solanaceae), commonly known as the ‘apple of Peru’ is widely associated with livestock poisoning. The clinical signs associated with its poisoning in ruminants appear within 6 hours of ingestion and are circling, tremors of the hind limbs, tachycardia, bloat, convulsions, coma and death. However, there is no published information on the toxicology of this plant in Kenya. This study documents Nicandra physaloides toxicity in two different zero-grazed dairy cattle herds that were inadvertently fed on Napier grass contaminated with Nicandra physaloides. In addition to the case studies, the toxicity of the aqueous extracts from the different parts of Nicandra physaloides was studied underexperimental conditions in mice. The 24 hour median lethal dose (LD50) was determined after intra-peritoneal injection (i.p.) of the aqueous extracts of the plant into white Swiss mice and found to be 1820, 2580 and 3620 mg/kg body weight for the leaves, fruits and whole plant respectively. The clinical signs in mice appeared within 30 minutes of inoculation and included coat, decreased locomotor activity, increased respiratory rate, gasping for air and leaping into the air before collapsing into coma and death. There were similarities in the symptoms of the spontaneous poisoning in cattle and in the experimentally induced poisoning in mice.Key words: Acute, Nicandra physaloides, toxicity, cattle, mice

Clinical, Haematological, Biochemical and Pathological Manifestations of Sub-Acute Toxicity of Nicandra Physaloides (L) Gaertn in Calves

No Abstract

A Preliminary Investigation On Suspected Plant Poisoning In The Faculty Of Veterinary Medicine Farm, Kabete, Kenya

An investigation on vegetation was carried out in one grazing paddock of the University of Nairobi, Veterinary Farm to establish the species of plants present and whether some were known to be poisonous. This investigation was carried out after reported cases of young dairy cattle manifesting signs of acute toxicity shortly after being grazed in this paddock. A check-list of the floristic composition of the site was exhaustively recorded and thirty two plant species were collected from the site. Five out of thirty two plants were suspected to be the possible cause of this poisoning as they have been reported before to have toxic effects. These were botanically identified as Ranunculus multifidus Forsk, Cassia didymobotrya Fres, Ricinus communis L., Datura stramonium L. and Momordica foetida Schum. It is concluded that some of these plants may be responsible for the poisoning and further studies on their level of toxicity and distribution in the farm needs to be determined.Une enquête sur la végétation a été conduite dans un enclos de pâturage de l'Université de Nairobi à la Ferme de la Faculté de Médecine vétérinaire pour voir les espèces de plante qui s'y trouvent et vérifier si certaines sont vénéneuses. L'enquête a été menée après que l'on ait signalé des cas de jeunes bovins laitiers avec des signes de toxicité aiguë peu de temps après avoir pâturé dans l'enclos. Une liste complète de la flore sur le site a été dressée et on en a recueilli trente deux espèces de plantes. Cinq des trente deux plantes étaient suspectées d'être la cause probable de l'intoxication parce qu'elles ont déjà été signalées auparavant comme ayant des effets toxiques. Ces plantes étaient botaniquement identifiées comme suit : Ranunculus multifidus Forsk, Cassia didymobotrya Fres, Ricinus communis L., Datura stramonium L. et Momordica foetida Schum. Il a été conclu que certaines de ces plantes peuvent être à l'origine de l'intoxication, et qu'il faudrait entreprendre des études supplémentaires sur leur taux de toxicité et leur répartition dans la ferme.Bulletin of Animal Health and Production in Africa Vol. 56 (1) 2008: pp. 19-2

Multiple Anthelmintic Resistance On A Sheep Farm In Kenya And Its Implication For Helminth Control

The occurrence of anthelmintic resistance in gastrointestinal nematodes in sheep on a farm in Kabete, Kenya was investigated between October 2005 and March 2006 when an outbreak of acute and fatal helminthosis occurred despite the use of ivermectin in worm control. The efficacies of locally available anthelmintics, namely, ivermectin, levamisole, levamisole rafoxanide combination and albendazole were evaluated based on faecal egg count reduction percentages (FECR%), clinical manifestation of helminthosis and post-mortem worm count (WC). All drugs tested showed low efficacies with FECR% of 44.2%, 77.0%, 66.9% and 42.3% for ivermectin, levamisole, levamisole rafoxanide combination and albendazole respectively. During the test period, 18 clinical cases were observed out of which 10 died. The mean WC in the dead animals declined gradually from 8905 in the pre-treatment period to 1545, 1529, 618, and 111 following ivermectin, levamisole, levamisole rafoxanide combination and albendazole treatments respectively. Haemonchus contortus and Trichuris ovis were resistant to all drugs tested. Trichostrongylus species were resistant to ivermectin and levamisole, but susceptible to albendazole. This necessitated treatment of the entire flock with albendazole and movement to new pastures and pens. No clinical case of helminthosis or mortality was recorded one month after the movement. This study indicated presence of multiple anthelmintic resistance on the farm as reported elsewhere in the country. Based on these findings, it is necessary to educate farmers on adapting integrated approach to helminth control with appropriate use of anthelmintics.Les cas de résistance anthelminthique chez les nématodes gastro-intestinaux dans une ferme ovine à Kabete au Kenya ont fait l\'objet d\'enquête entre octobre 2005 et mars 2006 lorsqu\'un foyer d\'helminthiase aigue et mortelle est apparu malgré l\'usage de l\'ivermectine pour le contrôle des vers. L\'efficacité des anthelminthiques disponibles sur place, à savoir : l\'ivermectine, le levamisole, l\'association levamisole/rafoxanide et l\'albendazole a été évaluée en tenant compte du taux de réduction du nombre d\'oeufs dans les fèces (% FECR), du signe clinique de l\'helminthiase et du nombre de vers à la nécropsie (NV). Tous les médicaments testés avaient une efficacité réduite avec des %FECR de 44,2% ; 77% ; 66,9% et 42,3% pour l\'ivermectine, le levamisole, l\'association levamisole/rafoxanide et l\'albendazole respectivement. Pendant la période de test, 18 cas cliniques ont été observés, parmi lesquels il y a eu dix morts. Le NV moyen chez les animaux morts baissait peu à peu, allant de 8905 avant le traitement à 1545, 1529, 618 et 111 après les traitements à l\'ivermectine, au levamisole, à l\'association levamisole/rafoxanide et à l\'albendazole respectivement. Haemonchus contortus et Trichuris ovis étaient résistants à tous les médicaments testés. Les espèces Trichostrongylus étaient résistantes à l\'ivermectine et au levamisole, mais sensibles à l\'albendazole, ce qui a rendu nécessaire le traitement de tout le troupeau à l\'albendazole et le déplacement vers de nouveaux pâturages et parcs à moutons. Aucun cas clinique d\'helminthiase ou de mortalité n\'a été enregistré un mois après le déplacement. Cette étude a montré la présence de résistance anthelminthique multiple sur la ferme comme signalé ailleurs dans le pays. A la lumière de ces conclusions, il est nécessaire de donner de l\'instruction aux éleveurs pour ce qui est de l\'adaptation de la méthode d\'approche intégrée au contrôle de l\'helminthe avec l\'usage judicieux des anthelminthiques.Bulletin of Animal Health and Production in Africa Vol. 55 (4) 2007: pp. 226-23

Ethnoveterinary Medicine: The prospects of integrating medicinal plant products in Veterinary Medicine in Kenya

Animal diseases are a major constraint to livestock production, drought animal power and the acceptability of companion animals. These diseases also impact negatively to the food security in our country. The use of synthetic drugs for disease management is always a challenge because of the unavailability of these drugs especially in rural areas, shortage of foreign exchange to import them, lack of finance to purchase them, drug resistance, misuse due to paucity of knowledge and environmental pollution. Medicinal plants products are part of the natural products that have been in use in traditional medicine and also a source of novel drugs. Therefore, the use of medicinal plant products would be a rational alternative to synthetic drugs. Ethnobotanical surveys carried out in many parts of Kenya have revealed a lot of plants being used in animal disease management. Specific plant extracts have been identified and screened by many researchers for their antimicrobial, anthelmintic, acaricidal, antiprotozoal activity and also their toxicity. There is therefore the need to look for ways on how these plants products will be available in the market and be integrated in the overall veterinary medicine practice in Kenya