Serosurvey of Brucella spp. infection in the Kafue lechwe (Kobus leche kafuensis) of the Kafue flats in Zambia

One of the diseases of veterinary and public health importance affecting the Kafue lechwe (Kobus leche kafuensis) on the Kafue flats is brucellosis, for which only scant information is available. During the 2003 (October), 2004 (December), and 2008 (July-December) hunting seasons in the Kafue flats, we conducted a study to determine the seroprevalence of Brucella spp. in the Kafue lechwe and to evaluate serologic tests for detection of Brucella spp. antibodies in lechwe. The Rose Bengal Test (RBT), competitive enzyme-linked immunosorbent assay (cELISA), and fluorescence polarization assay (FPA) were used. A total of 121 Kafue lechwe were hunted for disease investigations in 2003, 2004, and 2008 in the Kafue Flat Game Management Area. Of these, 21.6%, (95% confidence interval [CI]: 14.2-29.1%) had detectable antibodies to Brucella spp. The Kafue lechwe in Lochnivar National Park had higher antibody results than those in Blue Lagoon National Park (odds ratio=3.0; 95% CI: 0.94-9.4). Infection levels were similar in females (21.6%) and males (21.7%). Results were similar among RBT, FPA, cELISA tests, suggesting that these could effectively be used in diagnosing brucellosis in the Kafue lechwe. Our study demonstrates the presence of Brucella infections in the Kafue lechwe in two national parks located in the Kafue flats and further highlights the suitability of serologic assays for testing the Kafue lechwe. Because the Kafue lechwe is the most hunted wildlife species in Zambia, hunters need to be informed of the public health risk of Brucella spp. infection.     

A review of diseases of parasites of the Kafue lechwe (Kobus leche kafuensis).

The diseases of the Kafue lechwe (Kobus leche kafuensis) are reviewed in this paper. Kafue lechwe are an important natural resource for Zambia. Bovine tuberculosis is widespread within the lechwe population and they are host to many parasites, especially the warble Strobiloestrous vanzyli.     

Population growth of red lechwe, Kobus leche leche Gray, in the Busanga Plain, Zambia

An isolated population of red lechwe living in the Busanga Plain, Zambia, has been protected from human hunting since 1948. Probably as a result the population has increased, as indicated by reliable census data. From 1956 to 1972 this increase has very closely fitted an exponential rate; the calculated value of the infinitesimal rate of population increase (r) is 0–131, and the finite rate of increase is 14-0% per year. This exponential phase is considered to represent a segment of a logistic curve.     

The ecology of the lechwe, Kobus leche kafuensis Haltenorth, in Lochinvar National Park, Zambia, as affected by the Kafue Gorge hydroelectric scheme. Herbage digestibility in free-living antelope

A method of collecting rumen fluid from free-living antelope is presented, together with the in vitro procedure used to try to estimate the digestibility of the herbage grazed by them. Modifications to this procedure are suggested, which it is thought would allow the calculation of a meaningful equation relating these data to digestibility estimates obtained by a chemical method.     

Ciliate protozoa in the rumen of Kenyan zebu cattle, Bos taurus indicus, with the description of four new species

The composition of the fauna of rumen ciliates in zebu cattle in Kenya was surveyed and 13 genera containing 51 species with 19 formae were identified. Four new species were recognized, then described as Diplodinium africanum n. sp., Diplodinium namum n. sp., Eudiplodinium kenyensis n. sp., and Ostracodinium iwawoi n. sp. In addition, Buetschlia triciliata and Ostracodinium stokyi were found for the second and third times and described as Hsiungia triciliata n. comb. and Enoploplaston stokyi n. stat., with two formae, respectively. The species composition was similar to that of Indian zebu but several species were considered to originate from African native ruminants. In the percentage composition of genera, the numbers of Entodinium, which normally predominate in rumens in other areas, were very low.     

The nucleotide sequence of metallothioneins (MT) in liver of the Kafue lechwe (Kobus leche kafuensis) and their potential as biomarkers of heavy metal pollution of the Kafue River

The study determined heavy metal concentrations and MT1 nucleotide sequence [phylogeny] in liver of the Kafue lechwe. Applicability of MT1 as a biomarker of pollution was assessed. cDNA-encoding sequences for lechwe MT1 were amplified by RT-PCR to characterize the sequence of MT1 which was subjected to BLAST searching at NCBI. Phylogenetic relationships were based on pairwise matrix of sequence divergences calculated by Clustal W. Phylogenetic tree was constructed by NJ method using PHILLIP program. Metals were extracted by acid digestion and concentrations of Cr, Co, Cu, Zn, Cd, Pb, and Ni were determined using an AAS. MT1 mRNA expression levels were measured by quantitative comparative real-time RT-PCR. Lechwe MT1 has a length of 183bp, which encode for MT1 proteins of 61AA, which include 20 cysteines. Nucleotide sequence of lechwe MT1 showed identity with sheep MT (97%) and cattle MT1E (97%). Phylogenetic tree revealed that lechwe MT1 was clustered with sheep MT and cattle MT1E. Cu and Ni concentrations and MT1 mRNA expression levels of lechwe from Blue Lagoon were significantly higher than those from Lochinvar (p<0.05). Concentrations of Cd and Cu, Co and Cu, Co and Pb, Ni and Cu, and Ni and Cr were positively correlated. Spearman's rank correlations also showed positive correlations between Cu and Co concentrations and MT mRNA expression. PCA further suggested that MT mRNA expression was related to Zn and Cd concentrations. Hepatic MT1 mRNA expression in lechwe can be used as biomarker of heavy metal pollution.     

Condition, growth and reproduction in female red lechwe (Kobus leche leche Gray 1850)

Information on condition, growth and reproduction was collected from a sample of 155 female lechwe in the Linyanti Swamp, northern Botswana. Condition varied significantly with age, reproductive state and season and indications were found of relationships between body mass and the attainment of puberty in young females and body mass and the fertility of adult females. There were also indications that the population was under nutritional stress because of high water levels and that this had caused reductions in the growth rate and fertility of young females. It is suggested that the sensitivity of young females to adverse environmental conditions could be exploited to optimize population monitoring for conservation purposes by using them as an indicator class, rather than monitoring the entire population. Because of relationships between condition, growth and reproduction, it is also suggested that long-term monitoring of condition should form part of any effort to understand population dynamics.     

Investigating effects of parasite infection on body condition of the Kafue lechwe (<Emphasis Type="Italic">Kobus leche kafuensis</Emphasis>) in the Kafue basin

Background

The Kafue lechwe (Kobus leche Kafuensis), a medium-sized semi-aquatic antelope, is endemic to the Kafue basin of Zambia. The population of the Kafue lechwe has significantly dropped in the last decades leading to its subsequent inclusion on the red list of endangered species. In order to save the remaining population from extinction, it has become increasingly important that the impact of parasite infection and infestation on the Kafue lechwe is investigated.

Findings

Endoparasites accounted for the majority of parasites observed from a study of 40 Kafue lechwe occurring in the the Kafue basin. Amphistoma spp. were present in all animals examined, while Fasciola gigantica had a prevalence rate of 0.525 (95% CI: 0.36 to 0.69) and species of Schistosoma 0.3 (95% CI: 0.15 to 0.45). Among the ectoparasites, Strobiloestrous vanzyli, had a prevalence rate of 0.15 (95% CI: 0.03 to 0.27), while Rhipicephalus appendiculatus had a prevalence of 0.075 (3/40). Our findings indicate that body condition was not influenced by the parasitic infestation in Kafue lechwe. There was no association between sex and parasitic burden (odds ratio = 0.3, 95% CI: 0.8-1.3). However, an association between age and parasitic burden was observed as older animals above 15 years were more likely to get parasite infections than those aged between 1-5 years (odds ratio = 1.5, 95% CI: 1.1-2.4).

Conclusion

Overall, there was no evidence that parasitic infections and infestations adversely affected the lechwe population on the Kafue basin. These findings indicate that ecto- and endo-parasite infestation might not play a significant role in reducing the Kafue lechwe population on the Kafue basin.

     

Bilatorchis papillogenitalis n.g., n.sp. (Paramphistomidae: Orthocoelinae), a parasite of the red lechwe (Kobus leche Gray, 1850) from Zambia

Summary Bilatorchis papillogenitalis n.g., n.sp. from the red lechwe, Kobus leche Gray, 1850, from Zambia is described and illustrated. It is assigned to the subfamily Orthocoelinae Price & McIntosh, 1953 and distinguished from other members of the subfamily by the lateral and symmetrical position of the testes in the posterior third of the body between the caecal ends and the acetabulum, the intertesticular position of the ovary and Mehlis' gland and the limited extent of the caeca which end only at the level of the anterior border of the testes. A new type of genital atrium, papillogenitalis type is proposed for B. papillogenitalis, Calicophoron papillosum, Carmyerius parvipapillatus and, possibly, Orthocoelium parvipapillatum. The genus Cochinocotyle Gupta & Gupta, 1970 is moved to the subfamily Orthocoelinae.Supported by a scholarship grant under the 4th Education Project of the Philippines with the World Bank.Supported by a scholarship grant under the 4th Education Project of the Philippines with the World Bank.     

The ecology of the Kafue lechwe population of Zambia before the operation of hydro-electric dams on the Kafue River

Aerial surveys from 1970 onwards suggest a stable Kafue lechwe population of 94 000±9% on the Kafue Flats. The present distribution shows a contraction in dry and wet season range in comparison with 1953/54. Sex ratios of populations on both the North and South banks of the Kafue river do not differ significantly from unity. North bank males have a higher survival rate than South bank males. Survival curves for males and females on the South bank show the same pattern. For both the 1971 and 1972 breeding seasons 73% of South bank females older than 1½ years are expected to have bred successfully. The peaks of conceptions for both seasons are from mid-December to mid-March, suggesting a main lambing period from mid-July until mid-October. Present sex ratio, age structure, reproductive status and the reproductive cycle have been compared with 1961/62 data. Variation in physical condition, based on monthly measurements of the kidney fat percentage, dressing-out percentage and live weight, although influenced by the physiological demands of rut and pregnancy, is correlated with the availability of flood-plain grazing. The lowest values of condition parameters are found during the period of maximum flood, after the end of the rains (April/May), until the receding flood makes flood-plain grazing available, usually in early June. A high level of tuberculosis, lungworm infection and many other pathogens amongst the South bank population are reported. Animals from the North bank are thought to be in better physical condition. The Kafue Gorge dam, completed in 1971, and the Iteshi-teshi dam, at present under construction, will prolong the high flood period in wet years and prevent most flooding in dry years, both of these effects will reduce the carrying capacity of the flood plain for lechwe and a large reduction of the size of the population is expected to result from the operation of the dams.     

Rumen protozoa of the giraffe with a description of two new species

An analysis was carried out on the rumen ciliate population of giraffe. Eight giraffe shot on the Timbavati and adjoining private nature reserves in the north eastern Transvaal, South Africa, were sampled during 1973. Twenty-six species of ciliates were found in the giraffe rumen. Two new species were found and they are described viz. Entodinium longicorpum sp.n. and Eodinium bispinosum sp.n. The genus Ento-dinium with eleven species formed 41% of the total protozoa population. The holotrichs formed 19%, the genus Enoploplastron 16% and Eodinium 11% of the population.     

Hydrogenosomes in known species of rumen entodiniomorphid protozoa

Abstract Yeasts of the genus Kluyveromyces grew very slowly on methylamine as sole nitrogen source. Methylamine oxidase activity in cell-free extracts was very low. Under conditions known to separate methylamine oxidase from benzylamine oxidase in other yeast genera, only a single enzyme was detected in Kluyveromyces lactis . This enzyme could oxidize benzylamine, n -butylamine and (very poorly) methylamine. The enzyme lost no activity on heating at 45°C and had a high affinity and V _max for benzylamine and 1-aminoalkanes of long-chain length, with a very low affinity and V _max for methylamine. It is concluded that growth of K. lactis on methylamine involves only benzylamine oxidase, and that a methylamine oxidase of the type found in other yeasts does not occur.     

Gastrotrichs from interstitial fresh water,with a description of four new species

A study was performed on freshwater gastrotrichs living in the interstitial habitat of some lakes in Latium and of Lake Garda (Italy). Thirty-two chetonotids were collected, twenty-five of which could be identified. Four are new to science (Chaetonotus (Hystricochaetonotus) benacensis, Heterolepidoderma lamellatum, Ichthydium plicatum, I. squamigerum), and two are new to the Italian fauna (Heterolepidoderma macrops, H. majus). The faunistic composition of the lakes is compared with previous data. Interstitial gastrotrichs are less varied and abundant than those of epibenthos and periphyton, but often are of taxonomical and zoogeographical interest. The presence in the interstitial of some epibenthic and periphytic species demonstrates their capacity to colonize ecologically different habitats. The grain size of the substrate was not clearly correlated with faunal richness, but there was a possible influence of the amount of the organic detritus in the sediment. Morphological analysis showed a prevalence of small sized animals, with poorly ornamentated cuticular covering and well developed locomotory ciliature, as probable adaptations to interstitial life.     

Changes in experimental gillnet catches from the Kafue Floodplain, Zambia, since construction of the Kafue Gorge Dam

The Kafue Floodplain fishery produces an annual fish yield of about 5000 tonnes. The 1971 closure of the Kafue Gorge Dam downstream from the floodplain modified flooding patterns. Pre-impoundment studies predicted this modification would increase fish stocks. Experimental gillnets set in 1975 and 1976 caught 18 species on a regular basis, nine of which were abundant enough for comparison with catches in similar gillnet samples taken prior to completion of the Kafue Gorge Dam. Of these nine species, experimental gillnet catches of three predator species were smaller in 1975–76 than in 1969–70. Catches of only one species increased significantly. Whether this change is due to the modified flooding pattern is unclear; unusually dry flood conditions in 1973 and increased fishing effort may have contributed.     

On the Cyprideis species flock (Crustacea, Ostracoda) in Lake Tanganyika, with the description of four new species

Four new species, belonging to three genera, of ostracods from Lake Tanganyika are described: Mesocyprideis nitida sp.nov., Romecytheridea belone sp.nov., R. plegma sp. nov. and Cyprideis loricata sp. nov. The Cyprideis species flock of Lake Tanganyika now consists of 17 formally described species (16 endemic) in 6 genera (4 endemic). The geographical and ecological distribution of the four species is briefly discussed and some supplementary remarks on the radiation of the Cyprideis species flock in Lake Tanganyika are offered.