Assessment of impacts of tsetse and trypanosomosis control measures on cattle herd composition and performance in southern region, Ethiopia

This study was conducted to assess the impact of tsetse and trypanosomosis control measures on cattle herd size and composition, herd dynamics, and milk yield in Wolaita and Gamogofa Zones, southern Ethiopia. The study showed that the average number of cattle herd size in tsetse challenged areas was significantly higher than those in tsetse-controlled areas. The number of non-pregnant dry cows, bulls and oxen were significantly higher in tsetse challenged areas than the other two study areas. The rate of cattle addition to and disposal from the herd were significantly higher in tsetse challenged areas. Cows in Southern Tsetse Eradication Project (STEP) and community tsetse controlled areas were able to give 26-27?%, 25-29?% and 17-21?% more daily milk yield at the beginning, middle and end of lactation, respectively, than those in tsetse-challenged areas. In addition, cows in STEP and community tsetse controlled areas had lactation length longer by 1.20 to 1.35?months; age at first calving was shorter by 5.30 to 5.10?months; and calving interval was shorter by 4.20 to 3.20?months than cows in tsetse-challenged area, respectively. Hence, tsetse and trypanosomosis control both by the community and project would play key role in the improvement of cattle productivity.     

Community-based alternative breeding plans for indigenous sheep breeds in four agro-ecological zones of Ethiopia

Based on the results of participatory approaches to define traits in the breeding objectives, four scenarios of ram selection and ram use were compared via deterministic modelling of breeding plans for community-based sheep breeding programmes in four diverse agro-ecological regions of Ethiopia. The regions (and production systems) were Afar (pastoral/agro-pastoral), Bonga and Horro (both mixed crop-livestock) and Menz (sheep-barley). The schemes or scenarios differed in terms of selection intensity and duration of ram use. The predicted genetic gains per year in yearling weight (kilograms) were comparable across the schemes but differed among the breeds and ranged from 0.399 to 0.440 in Afar, 0.813 to 0.894 in Bonga, 0.850 to 0.940 in Horro, and 0.616 to 0.699 in Menz. The genetic gains per year in number of lambs born per ewe bred ranged from 0.009 to 0.010 in both Bonga and Horro. The predicted genetic gain in the proportion of lambs weaned per ewe joined was nearly comparable in all breeds ranging from 0.008 to 0.011. The genetic gain per year in milk yield of Afar breed was in the order of 0.018 to 0.020 kg, while the genetic gain per generation for greasy fleece weight (kg) ranged from 0.016 to 0.024 in Menz. Generally, strong selection and shorter duration of ram use for breeding were the preferred options. The expected genetic gains are satisfactory but largely rely on accurate and continuous pedigree and performance recording.     

Trypanosomosis and phenotypic features of four indigenous cattle breeds in an Ethiopian field study

We conducted a two-part study in the native home areas of four cattle breeds, Abigar, Gurage, Horro and Sheko, in south-western Ethiopia. The first part of the study investigated livestock keeper knowledge about trypanosomosis and trypanotolerance. For each breed 60 livestock keepers were interviewed, resulting in a total of 240 interviews. The second part of the study focused on biological evidence for trypanotolerance. Blood samples of about 100 head of cattle per breed were collected during peak trypanosomosis challenge period and analyzed for packed cell volume (PCV) and parasitaemia. In addition individual body measurements of the sampled animals were taken and the keepers provided some information regarding their animals. Livestock keeper interviews revealed that trypanosomosis was considered a major problem in all areas (95-100%). Almost all Abigar livestock keepers knew how trypanosomosis is transmitted, whereas only 34-52% of the keepers of the other breeds had that knowledge. Most Sheko keepers (75%) knew of trypanotolerance and claimed to have trypanotolerant animals in their own herds. Among the other three breeds the knowledge of trypanotolerance was much less (8-18%). A majority of the keepers were interested in purchasing trypanotolerant animals. PCV was highest among Horro (26.2) and Sheko (25.1) cattle whereas Abigar had the lowest PCV (20.0). Sheko were least infected by trypanosomes (6%) and had the lowest number of trypanocidal treatments per year (1 treatment/animal and year). Abigar cattle were most infected (23%) followed by Gurage (20%) and Horro (17%). Gurage had by far the highest number of treatments per animal and year (24). There were large differences between the number of cattle perceived by the keepers to be infected, and the number detected from blood sampled, among Abigar, Gurage and Horro. Sheko livestock keepers were better at correctly diagnosing trypanosomosis in their animals. It is concluded that Sheko cattle have higher trypanotolerance attributes of the breeds investigated and a better use of this breed could improve cattle health and household welfare in tsetse-infested areas.     

Estimation of tsetse challenge and its relationship with trypanosomosis incidence in cattle kept under pastoral production systems in Kenya

In an on-farm trial conducted amongst the Maasai pastoralists in Nkuruman and Nkineji areas of Kenya between April 2004 and August 2005 designed to evaluate the effectiveness of a synthetic tsetse repellent technology, we assessed the relationship between tsetse challenge and trypanosomosis incidence in cattle. Six villages were used in each area. Each of these villages had a sentinel cattle herd that was screened for trypanosomosis on monthly basis using buffy coat technique. Animals found infected at each sampling were treated with diminazene aceturate at 7 mg kg(-1) body weight. Treatments administered by the owners over the sampling intervals were recorded as well. Tsetse flies were trapped at the time of sampling using baited stationary traps and apparent tsetse density estimated as flies per trap per day (FTD). A fixed proportion (10%) of the flies was dissected and their infection status determined through microscopy. Blood meals were also collected from some of the flies and their sources identified using enzyme-linked immunosorbent assay (ELISA). Tsetse challenge was obtained as a product of tsetse density, trypanosome prevalence and the proportion of blood meals obtained from cattle. This variable was transformed using logarithmic function and fitted as an independent factor in a Poisson model that had trypanosomosis incidence in the sentinel cattle as the outcome of interest. The mean trypanosomosis incidence in the sentinel group of cattle was 7.2 and 10.2% in Nkuruman and Nkineji, respectively. Glossina pallidipes was the most prevalent tsetse species in Nkuruman while G. swynnertoni was prevalent in Nkineji. The proportions of tsetse that had mature infections in the respective areas were 0.6 and 4.2%. Most tsetse (28%) sampled in Nkuruman had blood meals from warthogs while most of those sampled in Nkineji (30%) had blood meals from cattle. A statistically significant association between tsetse challenge and trypanosomosis incidence was obtained only in Nkuruman when data was pooled and analyzed at the area but not at the village-level. In the later scenario, lagging tsetse challenge by 1 month improved the strength but not the significance of the association. These findings show that when the spatial unit of analysis in observational studies or on-farm trials is small, for instance a village, it may not be possible to demonstrate a statistically significant association between tsetse challenge and trypanosomosis incidence in livestock so as to effectively control for tsetse challenge.     

Effect on herd health and productivity of controlling tsetse and trypanosomosis by applying deltamethrin to cattle

Summary A large cattle ranch was established in 1954 in a heavily tsetse infested part of north-east Tanzania. Trypanosomosis was controlled for 30 years by prophylactic drugs but in 1988 drug resistance seemed to be developing as cases of trypanosomosis were being confirmed 4 or 5 weeks after treatment with isometamidium chloride (Samorin). Herd health had deteriorated and productivity was uneconomically low. In order to control the tsetse population the 8,000 cattle, grazing over 250 km², were regularly dipped in the synthetic pyrethroid deltamethrin (Decatix Cattle Dip and Spray formulation). Within a year the tsetse population, as monitored by traps, had decreased by more than 90%. Disease mortality decreased by 66% and a range of productivity measures such as calving percentages and weaning weights were raised to levels above those prevailing before the decline in herd health.

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Efecto En La Salud Y Productividad Del Hato Al Controlar Tse Tse Y Tripanosomiasis Aplicando Deltamethrin Al Ganado Vacuno

Resumen Un hato grande de ganado fue establecido en 1954 en un area densamente infestada del noreste de Tanzania. Tripanosomiasis fue controlada por 30 anõs usando drogas profilacticas, pero en 1988 resistencia al fármaco pareció desarrollarse ya que casos de tripanosomiasis fueron confirmados 4 o 5 semanas después del tratamiento con isometamidium chloride (Samorin). La salud del hato se habia deteriorado y la productividad era economicamente baja.Para controlar la población de tse tse, las ocho mil cabezas de ganado pastoreando sobre 250 km² fueron regularmente bañados con el pyrethroid deltamethrin sintético (Decatix para inmersion de bovinos y formulacion para aspersion). Dentro de un anõ la población de tse tse, monitoreada a través de trampas, habia disminuído mas del 90%. La mortalidad decrecio cerca de 66% y un rango de medidas de productividad tales como porcentajes de paricion y pesos al destete fueron incrementatdos a niveles arriba de aquellos que prevalecieron antes de la disminucion en la salud del hato.

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Controle De La Glossines Des Trypanosomoses Par Le Traitement Des Bovins A La Deltamethrine; Effet Sur La Sante Et La Productivite Du Troupeau

Résumé Une grande exploitation pour bovins a été fondée en 1954 dans une region du nord-est de la Tanzanie, hautement infestée par les glossines. Pendant 30 ans la trypanosomose a été controllée a l'aide de drogues prophylactiques mais en 1988 la resistance à ces drogues semble s'être developper car des cas de typanosomose ont été confirmés quatre au cinq semaines après traitement au chloride d'isometamidium (Samorin). L'état sanitaire du troupeau s'est deterioré et la productivité n'etait plus economiquement rentable.Afin de controler la population de glossines, les huit milles de bovins pâturant sur plus de 250 km², ont été régulièrement immergés dans des bains de deltamethrine, pyrethroide de synthèse (Decatix cattle dip et spray formulation). En un an, la population de glossines, evaluée par piégeage a diminuée de plus de 90%. La mortalité due à la maladie a dimunuée de plus de 66% et plusieurs paramètres de productivité, tel que le pourcentage de mise bas et le gain de poids ont atteint des niveaux superieurs a ceux enregistrés avant la degradation de l'état sanitaire du troupeau.

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Community-based tsetse fly control minimizes the effect of trypanosomosis on livestock in Metekel zone,Ethiopia

Tropical Animal Health and Production - Tsetse-related trypanosomosis threatens integrated crop-livestock production system in Ethiopia. Metekel zone is among the tsetse-infested areas in Ethiopia....     

Use of indigenous breeds of cattle and their crosses in Uganda as recipients for importedBos taurus embryos

Summary In July 1991, 29 frozen imported Holstein Friesian embryos were transferred into synchronised recipients in Uganda. Recipient cows and heifers from indigenous breeds of cattle and their crosses in Uganda were used. The project resultéd in 17 pregnancies confirmed by rectal palpation at 8 weeks. Twelve live calves were born of which 7 were heifers and 5 were bulls. One heifer calf died at one month of age from East Coast fever. One pregnant recipient died of East Coast fever 2 months before calving. Two recipients aborted in late gestation as a result of trauma incurred during fighting. Two calves were lost as a result of dystocia. The transfer work and calvings were performed at 3 different farms under varying conditions. The 11 surviving animals are being reared on a single unit where growth rates and performance data are being recorded.

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El Uso De Razas De Ganado Criollo Y Sus Cruces En Uganda Como Recipientes De EmbrionesBos Taurus Importados

Resumen En julio de 1991, se transfirieron 29 embriones importados de Holstein Friesian, en recipientes sincronizadas en Uganda fueron usadas como recipentes vacas y vaquillas de razas criollas y sus cruces. El proyecto resultó en 17 preñeces confirmadas mediante palpación rectal a las ocho semanas. Doce terneros nacieron, de los cuales siete fueron hembras y cinco fueron machos. Una de las terneras murió al mes de nacida de Fiebre de la Costa Este. Una de las recipientes preñadas murió la de la misma enfermedad dos meses antes del parto. Dos recipientes abortaron en el tercer tercio de la gestación, debido a traumas al pelear. Dos neonatos murieron durante partos distócicos. La transferencia se llevó a cabo en tres granjas differentes, bajo condiciones distintas. Los once sobrevivientes estan criándose en una sóla unidad, donde se estan registrando las tasas de crecimiento y otros parámetros.

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Utilisation En Ouganda De Races Bovines Locales Et De Leurs Croisements Comme Receveuses D'embryons Importes DeBos Taurus

Résumé En juillet 1991, 29 embryons Frison × Holstein importés ont été transférés à des vaches et génisses receveuses synchronisées appartenant à des races locales et croisées en Ouganda. Il en a résulté 17 gestations confirmées par palpation rectale à 8 semaines. Douze veaux vivants sont nés dont 7 étaient des femelles et 5 des mâles. Une velle est morte de theileriose à un mois, ainsi qu'une vache receveuse 2 mois après vêlage. Deux receveuses ont avorté en fin de gestation à cause d'un traumatisme provoqué durant une lutte. Deux veaux ont été perdus à la suite d'une dystocie. Le transfert d'embryons et les vêlages ont été réalisés dans 3 fermes différentes dans des conditions variées. Les 11 animaux survivants ont été élevés dans un seul lieu où leurs taux de croissance et les données de performance ont été enregistrés.

     

Recirculation of Trypanosoma brucei brucei in cattle after T. congolense challenge by tsetse flies

The effect of challenging cattle, chronically infected with Trypanosoma brucei brucei, with T. congolense on the development of the T. b. brucei infection was investigated. For this purpose, nine experimental animals were first infected with T. b. brucei through the bites of infected tsetse flies. Once the T. b. brucei had developed into a chronic infection, that was difficult to detect using routine parasitological diagnostic tools, seven of the experimental animals were challenged by tsetse flies infected with T. congolense. Two of the animals infected with T. b. brucei were kept as control. The infection with T. congolense resulted in a sudden increase in the parasitaemia of T. b. brucei. In the T. b. brucei control animals, on the other hand, the parasitaemia remained below the level of detection. The epidemiological repercussions of this increase in the parasitaemia of T. b. brucei after infection with T. congolense are discussed.     

Characterization of Doayo and Kapsiki taurine cattle breeds of Cameroon in their natural environment

Data were collected on live weight (LW), heart girth (HG), height-at-withers (HW), trunk length (TL), age, sex, and coat color of 207 taurines cattle—122 of the Doayo (Namchi) breed and 85 of the Kapsiki (Kirdi) breed. The animals, aged 1 to 20 years, were selected from 60 herds randomly selected from villages of Poli of Faro and Mokolo of Tsanga, divisions of the North and Far North Regions of Cameroon. The data were analyzed using the SAS program with a linear model, applying standard tests. Results indicated no breed effect (P > 0.05) in the growth trends of LW, HG, HW, and TL. HG and TL were highly significantly (P < 0.0001) related to LW. The growth pattern for the two breeds was the same since the linear contrast of least square means for the traits at various age groups did not differ (P > 0.05) significantly. The breeds attained maturity as from 4 years. In the absence of breed effect (P > 0.05), a single regression equation was established for the estimation of live weight as thus LW = - 244.42 ( ±22.57 ) kg + 2.49 ( ±0.23 ) HG + 1.04 ( ±0.25 ) TL {\hbox{LW}} = - {244}.{42 }\left( {\pm {22}.{57}} \right){\hbox{ kg}} + {2}.{49 }\left( {\pm 0.{23}} \right){\hbox{ HG}} + {1}.0{4 }\left( {\pm 0.{25}} \right){\hbox{ TL}} , with HG contributing up to 70% of total variation and TL, 2%. This equation could be used to develop a measuring band useful in the rural environment for commercial and clinical veterinary purposes.     

Immunization of cattle against Theileria parva bovis and their exposure to natural challenge

Theileria parva bovis isolates were tested for their immunizing capacity under natural field challenge on Willsbridge Farm in the highveld of Zimbabwe. Fifteen susceptible Sussex yearlings were immunized with the Boleni stock and 15 with a mixture of three isolates from the farm, using tick-derived sporozoite stabilates. No chemoprophylaxis was used. A dose of 0.1 ml of stabilate appeared to be safe in preliminary laboratory experiments, but the reactions were severe in the Sussex cattle and one died despite treatment. Twenty-nine immunized animals and 10 controls first experienced a mild infection, starting about 15 days after their arrival at the farm. Ten of the immunized animals and four controls had schizonts in peripheral lymph nodes for variable periods; one third of those had pyrexia. Nymphal Rhipicephalus appendiculatus ticks applied to three of the reacting immunized calves transmitted Theileria taurotragi to two animals and T. parva to a third. A second Theileria infection, due to T. parva bovis, was detected shortly after the first one. Schizonts were detected in seven out of 10 controls. Pyrexia was more severe and prolonged. Two of the controls died of theileriosis. At the same time schizonts were seen in three immune animals and eight of them had short periods of pyrexia. Intercurrent infections with Babesia bigemina, Borrelia theileri and Eperythrozoon were detected and may have contributed to the fever. Tick infestations were low during the exposure. In the second year of exposure, four out of eight new control animals had severe reactions, and one died. None of the immunized animals became ill, but one animal from the first year control group, which had not reacted previously, had clinical theileriosis. It is concluded that immunization provided an effective protection against field challenge.     

Comparative study of trypanosomosis in zebu and N'Dama cattle in the Gambia

Summary An experiment was conducted in The Gambia to compare trypanosomosis incidence between zebu and N'Dama cattle. It was considered important to compare the 2 breeds under identical management conditions and the animals were maintained together at 3 locations, traditionally managed and under a range of tsetse challenges. The results show that trypanosomosis incidence was significantly higher in zebu than in N'Dama. Titre of antibody againstTrypanosoma vivax measured by an IFAT showed a significant difference between zebu and N'Dama. Variations in packed cell volume were greater in zebu than in N'Dama.

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Estudios Comparativos De Tripanosomiasis En Cebu Y Ganado N'dama En Gambia

Resumen Se llev a cabo un experimento en Gambia para comparar la incidencia de tripanosomiasis en ganado cebú y N'Dama. Se consideró importante comparar las 2 razas bajo condiciones similares, en tres lugares diferentes con descargas minimas y máximas de tsetsé. Los resultados mostraron que la incidencia de tripanosomiasis fue significativamente mayor en cebú que en N'Dama. Los titulos de anticuerpos contraTrypanosoma vivax medidos mediante la prueba indirecta de anticuerpos fluorescentes, fueron significantivamente diferentes entre cebú y N'Dama. La variación en el volumen corpuscular celular fue mayor en cebú que en N'Dama.

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Etude Comparee De La Trypanosomose Chez Des Zebus Et Des Bovins N'dama En Gambie

Résumé Une expérience a été effectuée en Gambie pour comparer l'incidence de la trypanosomose entre des Zébu et des bovins N'dama. Il a été considéré comme important de comparer les 2 races dans des conditions d'élevage identiques, les animaux étant regroupés ensemble en 3 endroits, en élevage traditionnel et avec une pression glossinaire identique. Les résultats montrent que l'incidence de la trypanosomose a été plus élevée chez les Zébu que chez les N'dama. Le taux d'anticorps antiTrypanosoma vivax, mesuré par l'épreuve indirecte des anticorps fluorescents, a montré une différence significative entre les 2 races. Les variations de l'hématocrite ont été plus grandes chez les Zébu que chez les N'dama.

     

Analysis of genetic and cultural conservation value of three indigenous Croatian cattle breeds in a local and global context

It is widely accepted that autochthonous cattle breeds can be important genetic resources for unforeseeable environmental conditions in the future. Apart from that, they often represent local culture and tradition and thus assist in the awareness of ethnic identity of a country. In Croatia, there are only three indigenous cattle breeds, Croatian Bu?a, Slavonian Syrmian Podolian and Istrian Cattle. All of them are threatened but specialized in a particular habitat and production system. We analysed 93 microsatellites in 51 animals of each breed to get thorough information about genetic diversity and population structure. We further set them within an existing frame of additional 16 breeds that have been genotyped for the same marker set and cover a geographical area from the domestication centre near Anatolia, through the Balkan and alpine regions, to the north‐west of Europe. The cultural value was evaluated regarding the role in landscape, gastronomy, folklore and handicraft. The overall results recognize Croatian Bu?a being partly admixed but harbouring an enormous genetic diversity comparable with other traditional unselected Bu?a breeds in the Anatolian and Balkan areas. The Podolian cattle showed the lowest genetic diversity at the highest genetic distance to all remaining breeds but are playing an important role as part of the cultural landscape and thus contribute to the tourist industry. The genetic diversity of the Istrian cattle was found in the middle range of this study. It is already included in the tourist industry as a local food speciality. Current and future conservation strategies are discussed.     

Risk factors for foot and mouth disease seroprevalence in indigenous cattle in Southern Ethiopia: the effect of production system

A serological survey to investigate risk factors for Foot and Mouth Disease (FMD) occurrence was conducted between October 2007 and March 2008 in Southern Ethiopia. Antibodies against non-structural protein of FMD virus (using 3abc ELISA) were measured as indicator of exposure to the virus. The seroprevalence of FMD was 9.5% (95%CI = 7.7 – 11.3, n = 1020) and 48.1% (95% CI = 36.8 – 59.4%, n = 79), respectively at animal and herd levels. Within herd seropositivity was ranged from 6.7 to 46.7% with 18.6% (95%CI = 14.6 – 22.5%) risk of being seropositive for an animal in positive herds. The most important herd level risk factors identified were pastoral system (OR = 16.3, 95% CI = 2.0 -133.7) compared to sedentary, low altitude (OR = 7.5, 95% CI 1.4 -40.7) compared to high altitude, keeping cattle with small ruminants (OR = 5.1, 95% CI 1.0 -25.2) when compared to one species or alone. Seroprevalence was significantly higher (P <0.05) in South Omo than Sidama and Gamo Gofa areas. The odds of seropositivity were 2.8 and 2.3 times higher in the adult (>4 years) and maturing animals (3–4 years) compared to young age category (<3 years). Both multivariable logistic and negative binomial regressions depicted that production system was the major risk factor for FMD seropositivity. Consequently, higher prevalence of FMD in pastoral system where animals are an integral part of life has substantial livelihood and economic implications, which signifies the need for devising control measures.     

中国地方猪保种与利用工作的思考

简述了我国地方猪保种与利用工作的成效,提出了我国地方猪品种资源危机带有全局性,亟待采取应急措施;当前紧迫的任务是保持其遗传多样性,维持公猪现有的血统数;活体保种应立足于保种场,兼顾保种区;资源评估工作有待加强;有计划地开展有利于保种的优质商品猪生产。     

The estimated long-term impact of tsetse control on the size of the population of cattle in the Didessa Valley,Western Ethiopia

The long-term impact of tsetse control on cattle population size in the Didessa Valley, western Ethiopia, was analysed using an age-structured population model. A prior analytical assessment revealed that the risk of cattle dying in the tsetse-unprotected villages ranged from 4 to 9 times higher than in the tsetse-protected village. Model results show that during a period of 10 years the cattle population in the tsetse-protected village of Meti is likely to increase from 167 to 583 animals, while that in the adjacent tsetse-unprotected village of Gale remains almost constant. Model simulations also predict that improving the survival rate of calves in the tsetse-unprotected villages of Taikiltu and Temoloko (which presently have calf mortality rates of up to 35%) would bring a substantial increase in their cattle population.     

Prevalence and incidence of bovine trypanosomosis on the Adamaoua plateau in Cameroon 10 years after the tsetse eradication campaign

Between March 2004 and February 2005, the monthly incidence of trypanosome infections was measured in cattle from nine sentinel herds in the Adamaoua province of Cameroon. Three herds of 20 cattle each were kept on the plateau which has been cleared from tsetse flies about 10 years ago, three other herds were grazing in the tsetse infested valley whereas the last three were herded in the buffer zone. The cross-sectional study showed that the initial trypanosomosis prevalence was 1.8, 5.2 and 2.0% on the plateau, in the buffer zone and the valley, respectively. During the longitudinal study, the trypanosomosis incidence was high in the valley (3.7-20%) and the buffer zone (1.8-13.4%), whereas it was significantly lower (0-2.1%) on the plateau. Tsetse flies, mainly Glossina morsitans submorsitans and a few G. tachinoides, were caught in the valley and the buffer zone, but none on the plateau. The data indicate a low trypanosomosis risk on the plateau. Further entomological studies, however, are required to clarify the origin of the trypanosome infections on the plateau.