Opportunities for improving Nguni cattle production in the smallholder farming systems of South Africa

A total of 218 structured questionnaires were administered to determine the influence of production and socioeconomic factors on Nguni cattle farmers' constraints in the smallholder areas of South Africa. Cattle were mainly used for cash, milk and ceremonies. Cattle herd sizes were higher (P < 0.05) in the small-scale (23 ± 5.2) compared to the communal (9 ± 3.1) areas and mainly composed of cows. Most (75%) of the cattle owners were adult males and were more involved in herd management than adult females and youths. Shortage of feed and diseases/parasites were ranked by farmers as the most important constraints. The logistic regression model showed that odds ratio estimates of households experiencing cattle feed shortage and disease/parasite challenges were high for rangeland type, production system and gender of the household head. About 40 and 75% of the respondents in the sour and sweet rangelands reported that cattle condition deteriorates during winter, respectively (P < 0.05). Tick-borne diseases were the common causes of cattle mortality, especially in summer. Local crossbreds and Nguni were the common cattle breeds in the smallholder areas. African tradition worshippers had higher (P < 0.05) Nguni herd sizes (6 ± 3.2) than Christians (1 ± 0.5). Breeding season was undefined and mating system was largely uncontrolled in the communal areas. Farmers' socioeconomic and pedo-climatic situations should be considered when planning strategies for cattle development in the smallholder farming systems.     

Response of Nkedi Zebu and Ankole cattle to tick infestation and natural tick-borne,helminth and trypanosome infections in Uganda

A cross-sectional study was conducted in Soroti district of Uganda to establish important traits of Nkedi Zebu and Ankole cattle regarding their production performance responses to natural infections of trypanosomes, gastrointestinal nematodes, Theileria parva, Babesia bigemina, Anaplasma marginale and tick infestations. Over four visits between October 2006 to August 2007, tick counts were performed and blood, faecal samples and sera were collected from the Nkedi Zebu (295) and Ankole (165) cattle from 86 herds in six locations per visit. Low parasitological prevalence of trypanosome infection (<6%) and high prevalence of gastrointestinal nematode infections (>30%) with low faecal egg counts (110–300 eggs per gramme (EPG)) were observed in the Nkedi Zebu and Ankole cattle. Both breeds had high, moderate and low mean counts of Rhipicephalus appendiculatus (18.0–24.0), Rhipecephalus (Boophilus) decoloratus (3.6–10.3) and Amblyomma variegatum ticks (1.7–4.3), respectively. In addition, both breeds had similar mean packed cell volumes (26.4–31.2) and a similar percentage of animals were anaemic (14.5–36.6%). The Nkedi Zebu cattle further had higher mean optical density (OD) values for antibodies against T. parva (1.093–1.445) and A. marginale infections (0.573–0.583), and significantly (P < 0.001) higher mean OD values of antibodies against B. bigemina infections (1.07–2.175) than the Ankole cattle: T. parva (1.030–1.302); A. marginale (0.442–0.603) and B. bigemina infections (0.863–2.154). The Ankole cows produced significantly more (P < 0.001) milk per day (2.68 L) than the Nkedi Zebu cows (1.98 L), and the Ankole oxen had significantly higher (P < 0.05) draught power output (2.57 days/acre) than the Nkedi Zebu oxen (2.93 days/acre). Liveweights of calves aged 0–12 months of both breeds were comparable, suggesting that the Nkedi Zebu and Ankole cattle under similar disease challenge exhibited similar growth rates. In conclusion, the Nkedi Zebu cattle seem to possess a higher degree of disease resistance against endemic parasitic diseases, while the Ankole cattle seem to possess a moderate degree of disease resistance coupled with a moderate production potential.     

Factors influencing reproductive performance of cows from different Nguni ecotypes in southern Mozambique

The objective of this study was to assess the reproductive performance of two Nguni ecotypes (Nguni and Landim) raised in a subtropical environment to enhance strategies for livestock development and restocking programmes within the southern African region. Reproduction data collected between 1996 and 2009 from 365 cows of the Landim and Nguni ecotypes were analysed. From the results, ecotype, place of birth, year and season of birth/calving had significant effects on age at first calving (AFC) and calving interval (CI). Overall means for AFC and CI were 1,071 ± 166 days and 432 ± 85 days, respectively, while average calving rate was 88.0 ± 4.7%. Heifers born in the dry season had lower AFC than heifers born in the wet season. Heifers born at Impaputo Breeding Center were the youngest at first calving, followed by the South African born ones. Heifers of the Landim ecotype also calved younger than heifers of the Nguni ecotype. CI was shorter in wet seasons (main breeding seasons) than in dry seasons. Interaction between ecotype and year–season (p < 0.005) showed that, in wet and dry seasons, Nguni cows had shorter CI than the Landim. This study demonstrates for the first time a possible genotype-by-environment interaction between Nguni ecotypes. This might aid future cattle development and restocking programmes in southern Africa taking into consideration the adaptation of indigenous genotypes and climate change.     

Temporal changes in circulating levels of plasma interleukin-8 during peripartum period in Murrah buffaloes (Bubalus bubalis) under subtropical climate

The objective of this study was to elucidate the changes in circulating levels of plasma interleukin-8 (IL-8) during peripartum period in Murrah buffaloes (Bubalus bubalis). IL-8 was estimated in blood plasma of healthy peripartum Murrah buffaloes (n = 6) on days ±30, ±15, ±5, ±3, ±1 and 0 pre- and postpartum with respect to the day of parturition (day 0) in each of the two different seasons (hot–humid and spring). The mean microclimate Temperature–Humidity Index (THI) during spring season was significantly lower (p < 0.01) than the corresponding THI in hot–humid season. In both the seasons, plasma IL-8 remained lower in prepartum period (≤46.56 ± 14.08 pg/ml during spring and ≤ 73.18 ± 18.56 pg/ml during hot–humid season) than in the postpartum period (≥51.41 ± 13.82 pg/ml during spring and ≥ 84.13 ± 16.97 pg/ml in hot humid season). During spring, the IL-8 levels were significantly higher (P < 0.05) on days +5 and +15 postpartum in comparison to the IL-8 levels on days −30, −5, and −3 prepartum. During hot–humid season, IL-8 level was significantly higher (P < 0.05) on day +30 as compared to the IL-8 levels on days −30 and −5 prepartum. The correlation between IL-8 and mean microclimate THI was significant (r = 0.25, P < 0.01). From the results, it is concluded that peripartum period in buffaloes is associated with an inflammatory response leading to significantly higher plasma IL-8 during parturition and postpartum period than in the pre-partum period.     

Cattle ticks in Malawi

Four genera of cattle ticks were found and identified during two tick surveys: Amblyomma, Boophilus, Hyalomma and Rhipicephalus. Amblyomma variegatum was the only species found of genus Amblyomma. The genus Boophilus was represented by two species: B. microplus and B. decoloratus, and the genus Hyalomma by two species: H. truncatum and H. marginatum rufipes. Ten different species of Rhipicephalus were identified: R. appendiculatus, R. sanguineus, R. compositus, R. pravus, R. simus, R. kochi, R. reichenowi, R. tricuspis, R. masseyi and R. punctatus.The results are compared with those from previous investigations conducted by the late Dr S.G. Wilson.All sites at which the different species of cattle ticks were found, and the distribution of each tick are illustrated by a series of maps. The territorial distribution of the ticks is discussed. R. appendiculatus was collected at five sites in the Shire Highlands, an area in which their presence has not been previously demonstrated.     

Retrospective observations on the transmission of East Coast fever in Zimbabwe

Summary Records of 283 outbreaks of East Coast fever in Zimbabwe in the period 1914 to 1946 reveal that transmission of infection occurred throughout the year with peaks in January to March and May to July. The high level of transmission in January to March coincides with the known seasonal occurrence of adultRhipicephalus appendiculatus. It is suggested that transmission at other times of the year may have been effected by a population ofR. appendiculatus which did not exhibit a strictly seasonal life-cycle and has since been eradicated.

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Observaciones retrospectivas sobre la transmision de fiebre de la costa este en zimbabwe

Resumen Los registros de 283 brotes de Fiebre de la Costa Este en Zimbabwe en el periodo 1914–1946 revelaron, que la transmisión de la enfermedad ocurrió durante todo el a?o, con aumentos en enero-marzo y mayo–julio. El nivel alto de transmisión enenero-marzo coincide con la conocida ocurrencia estacional deRhipicephalus appendiculatus adultos. Se sugiere que la transmisión en otras épocas del a?o, podrían haber sido afectadas por poblaciones deR. appendiculatus el cual no exhibe cidos de vida estrictos y que ha sido erradicado.

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Observation a posteriori sur la transmission au zimbabwe de la theileriose

Résumé Les relevés de 283 foyers de la theileriose au Zimbawe durant la période 1914–1946 ont révélé que la transmission de l'infection s'effectue tout au long de l'année avec des pointes en janvier–mars et mai–juillet. Le haut degré de transmission de l'infection en janvier–mars co?ncide avec la fréquence saisonnière connue desRhipicephalus appendiculatus adultes. Ce fait suggère que la transmission pendant les autres époques de l'année pouvait avoir été réalisée par une population deR. appendiculatus qui ne possédait pas un cycle strictement saisonnier et qui a été éliminée depuis lors.

     

Observations on the numbers of the tickRhipicephalus appendiculatus on the ears of Zebu cattle in relation to hierarchical status in the herd

Summary A herd of21 East African Zebu cattle was observed when leaving a holding paddock and subsequently whilst grazing. The ranking positions of each animal in the herd over three periods during the dry season were ascertained. Frequent collections were also made of the adultRhipicephalus appendiculatus attached to the ears. It was shown that animals which tended to be at the front of the herd carried most ticks and therefore an animal's hierarchical position in the herd influenced the number of ticks which attached to it.This work was done whilst R.M.N. and T.E.F. were serving as Animal Health Officers with the Food and Agricultural Organization of the United Nations in a Government project for the improvement of tick control methods in Tanzania, supported by the United Nations Development Programme.     

The effect of flushing and stimulus of estrogenized does on reproductive performance of anovulatory-range goats

This study was conducted to determine whether flushing or the stimulus of estrogenized goats is necessary to achieve a high reproductive response in anestrous goats on rangeland. Does were feed-supplemented on rangeland (flushed, n = 20). Other group was exposed to estrogenized does during the mating period (stimulated, n = 20). A third group was both supplemented and stimulated (stimulated–flushed, n = 20) and other group grazed on rangeland only (control, n = 18). More goats in the stimulated and stimulated–flushed groups showed estrus during the first 5 days of joining (45% and 60%, respectively) than the control and flushed groups (11% and 5%, respectively; P < 0.05). Flushing did not improve prolificacy and reduced (P < 0.05) kidding rates (40% and 35% for the flushed and stimulated–flushed groups, respectively) compared to 67% and 55% for the control and stimulated groups, respectively. This experiment demonstrates potential shortcomings of use of flushing in range goats with inadequate nutrition during gestation.     

Survey of tick infestation in small ruminants of Miesso district,West Harergie,Oromia Region,Ethiopia

A survey was conducted to identify tick species and determine the prevalence of tick infestation in small ruminants of Miesso District, West Harergie Zone. Collection and identification of the ticks were undertaken from November 2007 to April 2008. All visible individual adult ticks were collected from the body of 328 goats and 40 sheep. The prevalence of tick infestation in goats and sheep was found to be 89.9% and 87.5%, respectively. In this study, ten species of ticks which grouped under four genera were identified. The most abundant species found in this study were Boophilus decoloratus (60%), Rhipicephalus pulchellus (25.1%), and Amblyomma gemma (11%). Hyalomma dromedarii was the minor species observed on goats. The difference in the prevalence of tick infestation between sheep and goats was not statistically significant (Χ ²   = 0.22, p = 0.63) but found to be statistically significant between male and females (Χ ²  = 9.8, p = 0.003). Attention should be given to the control and prevention of ticks, since they cause sever damage to the skins of small ruminants and thereby reduce the foreign exchange of the country; they also transmit some diseases which can cause sever loss to the productivity of these animals.     

Environment and farm factors associated with exposure to Theileria parva infection in cattle under traditional mixed farming system in Mbeere District,Kenya

The objective of this study was to investigate the relationship between seroprevalence to Theileria parva infection in cattle and potential environmental and farm-level effects in 80 farms under traditional crop–livestock system in Mbeere District, Kenya. A standardized questionnaire was used to collect the effects characteristics as related to T. parva infection epidemiology. Serum samples were collected from 440 cattle of all ages for detection of T. parva antibodies by the enzyme-linked immunosorbent assay technique. The association between the variables was assessed using a generalized estimation equation logistic regression model. The overall T. parva seroprevalence, accounting for correlation of responses, was 19.3% (95% confidence interval (CI) 14%, 25%). Two variables, “administrative division” and “presence of the vector tick on the farm”, were significantly associated with the T. parva seroresponse. Respectively, cattle from farms in Gachoka, Evurore, and Mwea divisions were (and their 95% CI) 1.3 (0.36, 4.8), 4.4 (1.2, 15.9), and 15.2 (4.9, 47.1) times more likely to be seropositive relative to those from Siakago Division (P = 0.000). Cattle from farms in which the vector tick was present were 2.9 (1.2, 6.7) times more likely to be seropositive (P = 0.011). Results of this study suggested that both environmental and farm factors may be associated with T. parva infection epidemiology in Mbeere District. Under such circumstances, characterization of environmental suitability for the vector tick and corresponding environment-specific farm management practices in the district is required both for improved understanding of the disease and in planning disease control programs.     

Genetic parameters for tick counts across months for different tick species and anatomical locations in South African Nguni cattle

The objective of the study was to characterise genetic parameters across months for different tick species and anatomical locations in South African Nguni cattle. Tick counts were conducted monthly, over a 2-year period, on 586 Nguni cattle under natural infestation, from four herds located in different provinces of South Africa. The counts were recorded for six species of ticks (Amblyomma hebraeum, Rhipicephalus evertsi evertsi, Rhipicephalus decoleratus and microplus (Boofilids), Rhipicephalus appendiculatus, Rhipicephalus simus and Hyalomma marginatum) attached on eight anatomical locations on the animals and were summed by species and anatomical location. Heritability estimates, phenotypic and genetic correlations were estimated on a monthly basis using mixed linear models, fitting univariate and bivariate sire models. Fixed effects considered were location, sex, year and age as a covariate. Tick counts were higher in the hot months, and A. hebraeum was the most dominant tick species. Heritability estimates for tick count varied by month and trait and ranged from 0 to 0.89. Genetic correlations were mostly positive, and low to high, with some negative correlations with high standard error. Phenotypic correlations were low to moderate. In general, high genetic correlations were observed between whole body count and the anatomical location counts, suggesting that it may not be necessary to conduct whole body counts. Counts from the belly and perineum appeared to be the most suitable surrogate traits for whole body count. These findings provide useful information for developing strategies for the practical implementation of genetic selection, as a supplement to the traditional tick control measures.     

Prevalence and species composition of ixodid ticks infesting horses in three agroecologies in central Oromia, Ethiopia

A cross-sectional study was conducted to determine the species composition and prevalence of ixodid ticks infesting horses in three agroecological zones in central Ethiopia. For this purpose, a total of 1,168 horses were examined for tick infestation. An overall prevalence of 39.04% of tick infestation on horses was recorded. A total of 917 adult ticks were collected from infested horses. Amblyomma, Boophilus, Rhipicephalus, and Hyalomma genera with the respective prevalence of 3.2%, 1.8%, 29.2%, and 4.7% were identified. In the study, Rhipicephalus evertsi evertsi was encountered with the highest prevalence (15.8%) whereas Amblyomma gemma was with lowest prevalence (1.5%). From the highland, Hyalomma marginatum rufipes (3.1%), Hyalomma truncatum (1.0%), and Boophilus decoloratus (0.3%) were identified. From the midland, R. evertsi evertsi (27.5%), Rhipicephalus pulchellus (18%), Amblyomma variegatum (3.6%), B. decoloratus (2.8%), H. marginatum rufipes (2.6%), H. truncatum (1.8%), and A. gemma (1.5%) were identified. R. evertsi evertsi, 107 (27.5%), was with the highest prevalence in the midland. From the lowland, R. pulchellus (22.3%), R. evertsi evertsi (20%), H. truncatum (3.6%), A. gemma (3.1%), B. decoloratus (2.3%), H. marginatum rufipes (2.1%), and A. variegatum (1.5%) were identified. In the lowland, R. pulchellus, 87 (22.3%), was the most abundant tick species. The overall prevalence of tick infestation on horses was significantly (P < 0.05) higher both in the midland, 225 (57.8%), and the lowland, 214 (54.87%), than the highland, 17 (4.4%). This suggests that horses in midland and lowland are at higher risk of tick infestation than those horses in the highland. Further studies on the role of ticks in transmission of diseases to equines and the importance of horses as alternative hosts in different parts of Ethiopia are needed.     

Seroprevalence estimation and management factors associated with high herd seropositivity for <Emphasis Type="Italic">Babesia bovis</Emphasis> in commercial dairy farms of Puerto Rico

A cross-sectional study was conducted to determine individual cow seroprevalence of Babesia bovis in adult lactating dairy cattle of Puerto Rico (PR), to assess the associations of farm management factors on herd seroprevalence, and to document the species of ticks infesting cattle within these farms. Antibody activity against B. bovis was determined using an indirect fluorescent antibody test (IFAT). Serum samples were obtained from 2,414 adult lactating dairy cattle from 76 randomly selected commercial dairy farms. Herd seroprevalence ranged from 0 to 51% with an overall individual cow seroprevalence for B. bovis of 26%. Ticks were collected from animals on 7 (9%) of the 76 participating commercial dairy farms. All collected ticks (n = 87) were Rhipicephalus (Boophilus) microplus. Factors associated with high herd seropositivity were dairy farms with calf but not heifer raising facilities (OR = 16, 95% CI = 3.0-86), having more than 4 neighbors with cattle (OR = 17, 95% CI = 1.6-178), same producer owning more than one farm (OR = 7.2, 95% CI = 1.6-32), and use of government services to apply amitraz on cattle (OR = 5.5, 95% CI = 1.5-20).     

Transmission of Theileriosis in the Traditional Farming Sector in the Southern Province of Zambia during 1995–1996

The incidence of first contact with the protozoan Theileria parva was determined in three traditional cattle herds in the Southern Province of Zambia in 1995 and 1996. The majority of first contacts occurred during the dry season in June, July and August, at a time of nymphal activity and in the absence of Rhipicephalus appendiculatus adults, indicating that larva to nymph transmission plays a more prominent role than nymph to adult transmission under the prevailing conditions.     

Conception of Jersey cattle in Turkey

To determine the effects of insemination season (IS; dry: May through October and rainy: November through April), lactation number (LN; heifers, primiparous or multiparous) and their interaction on non-return rate (NRR), conception rate (CR) to first-service and pregnancy loss (PL) of Jersey cattle in Turkey, over 1468 lactation records from 510 Jersey dairy cows were used. There was an interaction between LN × IS on NRR, CR to first-service (p < 0.01) and PL (p < 0.05). The NRR and CR to first-service of heifers inseminated during dry season and of primiparous inseminated during rainy season were higher (p < 0.01) than that of multiparous inseminated during both season. The NRR and CR of heifers and primiparous were higher (p < 0.05) than that of multiparous cows. The insemination of heifers during rainy season and of primiparous and multiparous during dry season increased (p < 0.01) the PL compared to the inseminations of heifers during dry season and of primiparous during rainy season. The PL was lower (p < 0.05) in primiparous than multiparous cows. The results demonstrate that the heifers have high fertility than the lactating, especially multiparous and that IS appeared to have a measurable impact on traits relating to conception of Jersey cattle in the each LN.     

Milk yield estimation of Ogaden cattle breed based on methods of weigh–suckle–weigh and calves’ growth

Daily milk yield of Ogaden cattle was estimated from milk suckled by 269 calves born and maintained between 1994 and 2004 at Haramaya University Beef Farm, Ethiopia. The weigh–suckle–weigh method and the growth of calves were used to estimate the yield. Mean predicted daily milk yield of the breed based on the weigh–suckle–weigh method was 4.39 ± 0.03 kg day⁻¹. Daily milk yield estimated from the growth of calves up to 3 months of age was 4.59 ± 1.43 kg day⁻¹. The milk yield was significantly affected by seasons of calving (p < 0.001), parities of the dams (p < 0.05), weeks of lactation (p < 0.001) and birth weights of calves (p < 0.05). A relatively higher milk yield was observed from cows calved during the long rain season. A higher milk yield was produced by cows in fifth parity. Heavier calves at birth suckled more milk than lighter calves. Daily milk yield was significantly higher in 3–6 weeks of lactation. The result of this study indicated that the milk yield produced by Ogaden breed was relatively higher than the yield of some Zebu breed measured by partial suckling system in Ethiopia and was comparable to the yield from Zebu cattle in the tropics estimated by the same method.     

Transmission of Theileria parva in the Traditional Farming Sector in the Southern Province of Zambia during 1997–1998

The incidence of first contact with the protozoan Theileria parva was determined in two traditional cattle herds in the Southern Province of Zambia during a period of average rainfall in 1997 and 1998, following a drought in the previous two years. Compared to that period, there was a marked increase in the number of rainy season first contacts attributable to transmission by Rhipicephalus appendiculatus adults. However, there were still more dry season contacts that resulted from nymphal transmission. These results highlight the important role that climate plays in the transmission of theileriosis in the Southern Province of Zambia.     

Seroprevalence of brucellosis and its contribution to abortion in cattle,camel, and goat kept under pastoral management in Borana,Ethiopia

The involvement of Brucella infection in causing abortion was investigated in a breeding female subpopulation of 283 cattle, 756 camels, and 757 goats. Serum samples were serially tested using the Rose Bengal test and complement fixation test. The study showed that anti-Brucella antibodies were prevalent in 10.6% (95% confidence interval (CI), 7.4, 14.9), 2.2% (95%CI, 1.4, 3.7), and 1.9% (95%CI, 1.1, 3.2) of cattle, camel, and goats, respectively. Abortion was more commonly reported in camels (23.4%) than cattle (13.8%) and goats (12.4%). The results of this study suggested that Brucella infections contribute significantly to abortion in cattle (odds ratio (OR), = 4.7; 95%CI, 2.0, 10.8) and goats (OR = 6.9; 95%CI, 2.2, 21.7) but not in camels. The number of young animals produced by breeding females seems to be apparently reduced in seropositive groups. Keeping more than two animal species at household level was found to be the risk factor for cattle (OR = 3.1; 95%CI, 1.2, 7.9) and camel (OR = 5.3; 95%CI, 1.2–23.5) seropositivity to Brucella infection when compared to those animals from households that keep only two animal species. This may suggest a possibility of cross species transmission of Brucella infection under such mixed herding. Wet season (OR = 4.8; 95%CI, 1.3, 18.1) was found to be associated with seropositivity in goats, linked to a coincidence of increased deliveries in flocks with possible excretion of Brucella organisms. The study results suggest that Brucella infection is the likely cause of abortion in cattle and goats while other causes largely outweigh brucellosis as a cause of abortion in camels in Borana, hence, contributing to reproductive loss.     

Copper,zinc, and iron concentrations in blood serum and diet of dairy cattle on semi-industrial farms in central Iran

The aim of this study was to evaluate the blood serum and diet concentrations of copper, zinc, and iron in Holstein dairy cattle kept under semi-industrial farming in Isfahan province, central Iran. Moreover, the effects of season, pregnancy, and daily milk yield on serum Cu, Zn, and Fe concentrations were also evaluated. The study was carried out on 12 semi-industrial Holstein dairy cattle farms. A total of 120 blood serum samples (60 in each season) and 24 diet samples (12 in each season) were collected in the summer and winter. The Cu, Fe, and Zn contents were assessed in samples using atomic absorption spectrophotometer. In the summer, the mean concentrations of Cu and Fe in serum samples were lower and higher than the critical level, respectively (P < 0.05). In total diet samples, the mean concentrations of Zn were significantly higher than critical level (P < 0.05). In summer, winter, and total diet samples, the mean concentrations of Fe were significantly higher than critical level (P < 0.05). The serum Cu and Zn concentrations were significantly higher in the winter than those determined in the summer (P < 0.05). The serum Cu concentrations were significantly higher in nonpregnant than those in pregnant dairy cattle (P < 0.05). No significant difference was observed in serum Cu, Zn, and Fe concentrations of dairy cattle in different daily milk yield groups. It can be concluded that Holstein dairy cattle reared under semi-industrial dairy farming were deficient in serum Cu concentrations, especially in summer. Further, high level of Fe in blood serum might be due to feeding of cattle with diet containing excess quantity of Fe.     

Herd- and animal-level risk factors for bovine leptospirosis in Tanga region of Tanzania

Leptospirosis is the zoonosis of worldwide distribution and common cause of economic loss and ill health among animals and human populations. A cross-sectional seroprevalence study, using a microscopic agglutination test (MAT) with a threshold titre of ≥1:160, to elucidate disease magnitude, distribution and associated risk factors in cattle in Tanga, Tanzania was conducted from May 2003 to January 2004. Serum (n = 655) samples collected from randomly selected herds (n = 130) were tested for antibodies against four different Leptospira interrogans serovars (Bataviae, Tarassovi, Hardjo and Pomona) used in the agglutination test. Positive titres were detected in 30.3% [95% confidence intervals (CI) = 26.7–33.9] of cattle and 58.5% (95% CI = 49.5–67.1) of herds, respectively. Of the 198 MAT positive serum samples, 98 (49.5%) were positive against serovar Hardjo, 80 (40.4%) were positive against serovar Tarassovi, 12 (6.1%) was positive against serovar Bataviae and eight (4%) were positive against serovar Pomona. Associations found to be statistically significant in univariate analyses (at P < 0.1) were assessed by multivariable logistic regression to control for confounding factors. The results showed that risk factors for cattle were pasture grazing [odd ratio (OR) = 2.83, 95% CI = 1.57–5.12, P = 0.001], presence of goats/sheep on the farm (OR = 1.73, 95% CI = 1.17–2.56, P = 0.001) and age of the animal (OR = 2.05, 95% CI = 1.42–2.96, P = 0.001), while concrete floor housing was protective (OR = 0.47, 95% CI = 0.30–0.74, P = 0.001). Herds managed under pasture grazing system were more likely to be sero-positive than those managed under zero grazed practices (OR = 9.31; 95% CI = 3.67–23.64 for grazing herd). We concluded that bovine leptospirosis is an endemic and locally widespread disease in Tanga and suggest that it may play a role in zoonotic transmission to humans.