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Recently, a wound dressing formulation, (Tri‐Solfen®, Medical Ethics Pty Ltd, Australia; TS) registered for use in ruminant husbandry in Australia, was registered for Foot‐and‐Mouth Disease (FMD) therapy in large ruminants in Laos, following clinical observations of improved welfare and healing following treatment of FMD lesions. In November 2019, an FMD outbreak in Cameroon provided an opportunity for a field trial, comparing clinical responses and recoveries to treatments on a sample of cattle (n = 36) comprising three equal groups of animals (n = 12), comparing responses to three treatments: (i) the application to lesions of TS, (ii) the administration of parenteral oxytetraycline commonly used for FMD in Cameroon; and (iii) an untreated control group (C). Appetite scores, lesion healing scores, and changes in dimensions of lesions, were recorded over a 15‐day study period. Cattle treated with TS achieved both superior appetite and lesion healing scores with more rapid reduction in dimensions of lesions than other groups. Farmer observations indicated the TS treatment group had a more rapid return to eating with cessation of excessive salivation, and more rapid return of mobility (walking) with absence of overt lameness. The findings indicate that although mortality is usually low in FMD outbreaks, the disease is a debilitating and painful disorder with negative animal welfare impacts that should be addressed. All farmers expressed their desire that the product be made available for use in their region and modelling indicates that TS therapy imposes no additional financial burden on farmers, with the treatment likely to be provided at a similar or reduced cost to current treatment choices. As use of antibiotics for treatment of a viral disease potentially increases pressures for development of antimicrobial resistance and residues in the food chain, TS as an alternative non‐antimicrobial therapy should be promoted for wider use in FMD outbreaks.

To embark on an anti-vectorial fight against mechanical vectors of animal trypanosomosis, investigations were undertaken in order to determine the abundance, species diversity and daily activity of tabanids in a cattle ranch in Gabon. The nzi and vavoua traps were used to catch tabanids in three divisions of this ranch. In this study, 616 tabanids were captured: 349 (56.66%) in Division 1, 226 (36.69%) in Division 2 and 41 (6.66%) in Division 3. In the first Division, T. taeniola was the most abundant species with an Apparent Density (ADT) of 2.2, followed by H. pluvialis (ADT = 1.05). In the second Division, H. pluvialis was most abundant with ADT of 1.6, followed by T. taeniola (ADT = 0.38). In the last Division, the most abundant species was H. pluvialis (ADT = 0.15). Comparing the relative abundance of catches with sites (Divisions), we realized that there was no statistically significant difference in catches with trapping sites. It was noticed that Division 3 recorded the highest diversity index values. We realized that the nzi trap recorded higher tabanid catches than the vavoua trap. The diurnal activity rhythm of the most frequent species encountered slightly differed with prospection sites.

Background: Tabanid flies are a neglected group of haematophagous dipterans, yet contains 4400 species, regrouped under 144 genera. They are mechanical vectors of important pathogens, including viruses, bacteria and protozoa of humans, domesticated and wild animals. As it is over 50 years since publication of a preliminary nationwide record of tabanids of Cameroon identified 84 species, updated information is provided.Objective: To provide current data on the species composition, abundance and distribution of Tabanidae of Cameroon in the 5 main agro-ecological zones (AEZs).Methods: From 2015-2017, a systematic entomological prospection using Nzi, Vavoua, Biconical and Sevi traps (N=106) was conducted in 604 trap-points over 11,448 traps days, in the 5 main AEZs of Cameroon.Results: A total of 25,280 tabanid specimens were collected, identifying 25 species with 8 not previously documented in Cameroon, including: Tabanus Latipes Macquart, 1838 (1 ♀), Tabanus ricardae Surcouf, 1906 (1 ♀), Tabanus fasciatus Fabricus, 1775 (32 ♀♀, 6♂♂), Haematopota pluvialis Linnaeus, 1758 (18 ♀♀), Haematopota decora Walker, 1850 (19 ♀♀, 3 ♂♂), Haematopota nigripennis Austen, 1914 (18 ♀♀), C. distinctipennis Austen, 1906 (47 ♀♀, 5 ♂♂) and Ancala fasciata Fabricus, 1977 (34 ♀♀, 7 ♂♂). The distribution maps of the newly identified tabanids differed between AEZs, with most from the Guinean savanna. The highest Tabanidae apparent density (ADT) was recorded in the Sudan savanna region and the mean apparent densities of species with type-localities was statistically significantly different (Student t-test=2.519, df=24, P=0.019). The highest species diversity was found in the rain forest.Conclusions: This study increased the list of Tabanidae recorded in Cameroon from 84 species in the preliminary record to 92 species, with most of the newly identified species occurring in the Guinean savanna AEZ. The high diversity and abundance of Tabanidae in the livestock/wildlife interface areas of the rain forests and Sudan savanna AEZs respectively, suggests risk of mechanical transmission risk of pathogens. Investigations of the microbiota within the Tabanidae in the different AEZs to define their role as disease vectors are proposed.

Recently, a wound dressing formulation, (Tri-Solfen®, Medical Ethics Pty Ltd, Australia; TS) registered for use in ruminant husbandry in Australia, was registered for Foot-and-Mouth Disease (FMD) therapy in large ruminants in Laos, following clinical observations of improved welfare and healing following treatment of FMD lesions. In November 2019, an FMD outbreak in Cameroon provided an opportunity for a field trial, comparing clinical responses and recoveries to treatments on a sample of cattle (n = 36) comprising three equal groups of animals (n = 12), comparing responses to three treatments:(i) the application to lesions of TS, (ii) the administration of parenteral oxytetraycline commonly used for FMD in Cameroon; and (iii) an untreated control group (C). Appetite scores, lesion healing scores, and changes in dimensions of lesions, were recorded over a 15-day study period. Cattle treated with TS achieved both superior appetite and lesion healing scores with more rapid reduction in dimensions of lesions than other groups. Farmer observations indicated the TS treatment group had a more rapid return to eating with cessation of excessive salivation, and more rapid return of mobility (walking) with absence of overt lameness. The findings indicate that although mortality is usually low in FMD outbreaks, the disease is a debilitating and painful disorder with negative animal welfare impacts that should be addressed. All farmers expressed their desire that the product be made available for use in their region and modelling indicates that TS therapy imposes no additional financial burden on farmers, with the treatment likely to be provided at a similar or reduced cost to current treatment choices. As use of antibiotics for treatment of a viral disease potentially increases pressures for development of antimicrobial resistance and residues in the food chain, TS as an alternative non-antimicrobial therapy should be promoted for wider use in FMD outbreaks.

The rangelands of the Vina Division on the Adamawa Plateau are densely infested with Stomoxyinae, but little is known about their species composition and ecology. A trap-transect survey was carried out in three villages: Galim, Mbidjoro, and Velambai, using Nzi (n = 3), Vavoua (n = 3), and Biconical (n = 3) traps, all baited with octenol. Three traps of each trap type were set in each of the study villages, and collections were carried out daily. In total, 3,762 Stomoxys spp. were collected from October 2016 to June 2017 and identified using standard keys into five species: Stomoxys niger niger, S. calcitrans, S. niger bilineatus, S. omega, and S. xanthomelas. Galim recorded the highest apparent density of stomoxyines (30 stomoxyines/trap/day) with a statistically significant difference (p<0.05). The Vavoua trap was an ideal tool for Stomoxyinae collection. Stomoxyines abundantly occurred at the end of the dry season (March 2017) and beginning of the rainy season (May 2017). The monthly rainfall positively influenced monthly ADTs of Stomoxyinae. Their diurnal biting activity was bimodal in the rainy season and unimodal in the dry season. The daily activity peak was between 14 h and 16 h with a mean temperature of 31°C, a mean wind speed of 1.5 m/s, and a mean humidity of 50%. The daily trap catch was positively influenced by temperature and wind speed but negatively influenced by rainfall and air humidity. Weather variables influenced Stomoxys spp. monthly and daily ADTs.

Une enquête entomologique de type transversale, basée sur l’utilisation des pièges Vavoua, a été réalisée pendant 5 jours dans la localité de Campo et ses environs (sud Cameroun) afin de connaître l’abondance et la diversité spécifique des vecteurs mécaniques de trypanosomes. Au total, 162 mouches hématophages ont été capturées dont 137 mouches (85 %) au village Mabiogo, 17 (10 %) en zone de mangrove et 8 (5 %) en forêt avec des densités apparentes respectives de 2,74 ; 0,34 et 0,16 mouche/piège/jour. Neuf espèces dont quatre espèces de Tabanidae et cinq espèces de Stomoxyinae ont été ainsi identifiées. Les espèces appartenant à la famille des Tabanidae ont été constituées par Chrysops silacea Austen 1907 (7 %), Tabanus taeniola Palisot de Beauvois 1806 (7 %), Chrysops distinctipennis Austen 1906 (20 %) et Tabanus par Walker 1848 (64 %). Par contre, les espèces de la sous famille des Stomoxyinae ont été représentées par : Stomoxys niger niger Macquart 1851 (84,5 %), Stomoxys omega Newstead 1907 (12,8 %), Stomoxys xanthomelas Roubaud 1937 (1,4 %), Stomoxys calcitrans L. 1758 (0,7 %) et Stomoxys niger bilineatus Grünberg 1906 (0,7 %). La présence de ces vecteurs dans cette zone pourrait suggérer une potentielle transmission mécanique du trypanosome humain mais également de la filariose à Loa loa. Aussi, une étude plus approfondie de ces insectes est en cours pour préciser leur importance épidémiologique et leur dynamique saisonnière., A cross-sectional entomological survey, based on the use of Vavoua traps, was carried out for 5 days in the locality of Campo and its surroundings (south Cameroon) in order to investigate the abundance and the specific diversity of the mechanical vectors of trypanosomes. A total of 162 hematophagous flies were captured, including 137 flies (85 %) in the Mabiogo village, 17 (10 %) in the mangrove zone and 8 (5 %) in the forest with apparent densities of 2.74; 0.34 and 0.16 fly/trap/day. Nine species including four tabanids species and five stables flies species were identified. The species belonging to the Tabanidae family consisted of Chrysops silacea Austen 1907 (7 %), Tabanus taeniola Palisot de Beauvois 1806 (7 %), Chrysops distinctipennis Austen 1906 (20 %) and Tabanus par Walker 1848 (64 %). However, species of the Stomoxyinae were represented by Stomoxys niger niger Macquart 1851 (84.5 %), Stomoxys omega Newstead 1907 (12.8 %), Stomoxys xanthomelas Roubaud 1937 (1.4 %), Stomoxys calcitrans L. 1758 (0.7 %) and Stomoxys niger bilineatus Grünberg 1906 (0.7 %). The presence of these vectors in this zone could suggest a potential mechanical transmission of the human trypanosome but also of Loa loa filariasis. A more detailed study of these insects is under way to clarify their epidemiological importance and their seasonal dynamics.

La présente étude avait pour but de déterminer la diversité des macroinvertébrés afin de connaitre l’état de santé des rivières du Parc National de Moukalaba Doudou (PNMD) situé au sud-ouest du Gabon. L’échantillonnage de ces macroinvertébrés a été fait dans quatre stations différentes de ce parc. Au total, 1008 individus de macroinvertébrés, repartis en 5 classes, 12 ordres et 54 familles ont été identifiés. La classe des insectes a été la mieux représentée avec plusieurs ordres dont les Ephéméroptères, les Trichoptères, les Coléoptères, les Diptères et les Plécoptères. L’analyse des indices de diversité a révélé que 50 % des rivières échantillonnées sont peu diversifiées bien que les facteurs physico-chimiques de ces eaux soient favorables au développement des macroinvertébrés. Ces rivières, ne présentant pas de taxon dominant, semblent cependant ne pas être perturbées. Les résultats de l’indice EPT/C ont montré une prédominance des groupes des Ephéméroptères, des Plécoptères, des Trichoptères (EPT) qui sont des organismes polluo-sensibles. Ces résultats suggèrent que les rivières du nord-est et du sud-est du PNMD sont de bonne qualité biologique mais devraient faire l’objet d’une bio-surveillance., The purpose of this study was to determine the diversity of Macroinvertebrates and to determine the health status of rivers in the Moukalaba Doudou National Park, in South-Western of Gabon. Sampling of these Macroinvertebrates was done at four different stations in this park. In total, 1008 individuals of Macroinvertebrates, divided into 5 classes, 12 orders and 54 families were identified. The class of insects was best represented with several orders including the Ephemeroptera, the Trichoptera, the Coleoptera, the Diptera and the Plecoptera. Moreover, the analysis of the diversity indices revealed that 50 % of the rivers sampled are not very diversified although the physicochemical factors of these waters are favorable to the development of Macroinvertebrates. Moreover, these rivers, which do not have a dominant taxon, seem not to be disturbed. The results of the EPT/C index showed a predominance of the groups of Ephemeroptera, Plecoptera and Trichoptera (EPT) which are polluo-sensitive organisms. These results show that the North-Eastern and South-Eastern rivers of the Moukalaba Doudou National Park are of good biological quality but should be subject to bio-surveillance.