Immunization of young heifers with staphylococcal immune evasion proteins before natural exposure to Staphylococcus aureus induces a humoral immune response in serum and milk

Background: Staphylococcus aureus, a leading cause of mastitis in dairy cattle, causes severe mastitis and/or chronic persistent infections with detrimental effects on the cows' wellbeing, lifespan and milk production. Despite years of research there is no effective vaccine against S. aureus mastitis. Boosting of non-protective pre-existing immunity to S. aureus, induced by natural exposure to S. aureus, by vaccination may interfere with vaccine efficacy. The aim was to assess whether experimental immunization of S. aureus naïve animals results in an immune response that differs from immunity following natural exposure to S. aureus. Results: First, to define the period during which calves are immunologically naïve for S. aureus, Efb, LukM, and whole-cell S. aureus specific serum antibodies were measured in a cohort of newborn calves by ELISA. Rising S. aureus specific antibodies indicated that from week 12 onward calves mounted an immune response to S. aureus due to natural exposure. Next, an experimental immunization trial was set up using 8-week-old heifer calves (n = 16), half of which were immunized with the immune evasion molecules Efb and LukM. Immunization was repeated after one year and before parturition and humoral and cellular immunity specific for Efb and LukM was determined throughout the study. Post-partum, antibody levels against LukM and EfB were significantly higher in serum, colostrum and milk in the experimentally immunized animals compared to animals naturally exposed to S. aureus. LukM specific IL17a responses were also significantly higher in the immunized cows post-partum. Conclusions: Experimental immunization with staphylococcal immune evasion molecules starting before natural exposure resulted in significantly higher antibody levels against Efb and LukM around parturition in serum as well as the site of infection, i.e. in colostrum and milk, compared to natural exposure to S. aureus. This study showed that it is practically feasible to vaccinate S. aureus naïve cattle and that experimental immunization induced a humoral immune response that differed from that after natural exposure only.</p

A Retrospective Study of Reproductive Conditions in Bitches in Nairobi

A twenty year retrospective study was carried out in the Small Animal Clinic, University of Nairobi, Kenya and in a private Small Animal Clinic in Nairobi between the years 1988 to 2008. A total of 6548 bitches had been presented with reproductive problems. The cases were categorically grouped according to the type of infertility diagnosed. Non-infectious infertilities were sixty nine percent and infectious types were thirty one percent. Only two percent of the latter were confirmed in one clinic. 23.20 % of non-infectious infertility were managerial, 29.1% anatomical and 7.80% physiological types while 39.80 % were unclassified miscellaneous cases. The cases classified under infectious infertility consisted of; vaginitis/endometritis/metritis (36.3%), pyometra (25.3%), abortions (21.5%), vaginal discharges (11.7%) and miscarriages (5.1%). The incidence of infertilities was highly common in breeds of German shepherd (39%), Doberman (6%), Rottweiler (12%) and their crosses (43%). The percentage of the reproductive cases presented in both clinics had no statistical difference at (

A note on milking practices in the smallholder dairy production systems of Nairobi and its environs

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Seasonality and occurrence of canine babesiosis in Nairobi and its environs in changing climatic patterns

Canine babesiosis caused by different babesia species is a protozoal tick-borne disease with worldwide distribution and global significance. This study was carried out to establish the seasonality and occurrence of canine babesiosis in dogs as observed in Nairobi area using data from the Small Animal Clinic, University of Nairobi over a period of twenty years (1989 – 2009). Thespatio-temporal distribution of the disease is also presented in relationship to age, sex and breeds affected. The warm and humid season played a key role in the occurrence and spread of the disease.The rainy (wet) season recorded a high incidence 54.90%compared to the dry season 45.10%. In the rainy season the occurrence of the disease was in the long rains (April to June) and short rains (October to December) at 52% and 48% respectively.This study concludes that high cases of babesiosis occur throughout all the seasons in the tropical and sub-tropical regions and therefore recommend good tick control strategies in all the seasons to reduce incidences.Keywords: Epidemiology, Babesiosis, Rains, Tropic

A Typical Actinobacillosis in an Adult Friesian Cow

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Research Article: Animal Welfare The Impact of Customized Lectures on Knowledge and Perceptions of Veterinary Students on Animal Welfare and Related Legislations

A study was designed to investigate the knowledge and perceptions of animal welfare and related legislations among graduating Bachelor of Veterinary Medicine students from the University of Nairobi, Kenya. A questionnaire was designed and administered to assess understanding, poor attributes, good provisions, legislations’, knowledge and sources of general information on animal welfare. The percentage responses to thequestions before and after the customized lecture series were determined and differences compared using a paired t test. The level of awareness of animal welfare issues among students before and after the customized lectures was 33.11% and 68.03% respectively. Significant differences at p ≤ 0.05 on all the attributes assessed was observed. p=0.0056 on the understanding of animal welfare, p=0.0232 on what constitutes poor animal welfare and p=0.025 on conditions necessary to ensure a state of good animal welfare. A 50% increase in awareness of legislations on  animal welfare was recorded after the lecture series. The major source of information on animal welfare was from the lecture series offered. This study confirms that inclusion of the customized lectures on animal welfare in training veterinary students was effective in promoting awareness on animal welfare. The contents of these lectures should be included in relevant subjects taught to students at the Faculties of VeterinaryMedicine.Keywords: Animal welfare, Five freedoms, Legislations, Perceptions

Short Communication: A Typical Actinobacillosis in an Adult Friesian Cow

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Clinical Presentation, Treatment and Management of Some Rabbit Conditions in Nairobi

A retrospective study carried from records at the Small Animal Clinic, University of Nairobi between the years 1999 to 2010 to investigate the occurrence of rabbit conditions /diseases found a total of fifty clinical cases to have been presented within the period. Annual variations in the number of cases presented were noted with the highest incidence of 54% in the year 2010. The incidence of infectious conditions were ear canker 36% (18/50), gastrointestinal conditions 22% (11/50), pneumonia 12% (6/50) and skin conditions at 6% (3/50). Single cases of Ehrlichiosis, vaginal prolapse and Vitamin E /selenium deficiency were observed. Cases classified under routine health checks accounted for 18% (9/50) of the conditions. The distribution of the diseases by breed was New Zealand White 40% (20/50), California White 20% (10/50), crosses 24% (12/50), Dutch 10% (5/50), and Kenya White 6% (3/50). More female cases were noted relative to males at 78% (39/50) and 22% (11/50), respectively. A similar prevalence was also observed as per the age group where the adults were more than the kittens (baby rabbits). The mortality rate of the cases was 26% (13/50). Pneumonia had the highest case fatality rate at 83% (5/6) followed by gastrointestinal conditions 36% (4/11) and ear canker 22% (4/18). The findings of this study revealed that ear canker, intestinal coccidiosis and pneumonia were the most prevalent conditions affecting rabbits in Nairobi, Kenya.Une &#233;tude r&#233;trospective bas&#233;e sur les dossiers de la Small Animal Clinic (clinique des petits animaux) de l&#8217;Universit&#233; de Nairobi, effectu&#233;e entre les ann&#233;es 1999 et 2010 dans le but d&#8217;&#233;tudier la pr&#233;sence de maladies du lapin, a relev&#233; un total de cinquante cas cliniques qui avaient &#233;t&#233; pr&#233;sent&#233;s durant cette p&#233;riode. Les variations annuelles du nombre de cas pr&#233;sent&#233;s ont &#233;t&#233; not&#233;es, l&#8217;incidence la plus &#233;lev&#233;e de 54% ayant &#233;t&#233; enregistr&#233;e en 2010. L&#8217;incidence des maladies infectieuses se pr&#233;sentait comme suit : le chancre de l&#8217;oreille 36% (18/50), les troubles gastro-intestinaux 22% (11/50), la pneumonie 12% (6/50) et les affections cutan&#233;es 6% (3/50). Des cas isol&#233;s d&#8217;ehrlichiose, de prolapsus vaginal et de carence en vitamine E / s&#233;l&#233;nium ont &#233;t&#233; relev&#233;s. Les cas class&#233;s au titre des examens m&#233;dicaux de routine repr&#233;sentaient 18% (9/50) des maladies. La r&#233;partition des maladies par race se pr&#233;sentait comme suit: Blanc de Nouvelle-Z&#233;lande 40% (20/50) ; Blanc de Californie 20% (10/50); races crois&#233;es 24% (12/50); N&#233;erlandais 10% (5/50); et Blanc du Kenya 6% (3/50). On a not&#233; plus de cas chez les femelles par rapport aux m&#226;les, respectivement 78% (39/50) et 22% (11/50). Une pr&#233;valence similaire a &#233;galement &#233;t&#233; observ&#233;e suivant le groupe d&#8217;&#226;ge o&#249; les adultes &#233;taient plus nombreux que les lapereaux. Le taux de l&#233;talit&#233; &#233;tait de 26% (13/50). La pneumonie avait le taux de l&#233;talit&#233; le plus &#233;lev&#233; de 83% (5/6), suivie par les affections gastro-intestinales et le chancre de l&#8217;oreille respectivement avec des taux de l&#233;talit&#233; de 36% (4/11) et de 22% (4/18). Les r&#233;sultats de cette &#233;tude ont r&#233;v&#233;l&#233; que le chancre de l&#8217;oreille, la coccidiose intestinale et la pneumonie &#233;taient les maladies courantes affectant les lapins &#224; Nairobi (Kenya).Mots-cl&#233;s: Maladies des lapins; chancre de l&#8217;oreille; coccidiose; pneumoni