Alaster Samkange

Dr. Alaster Samkange

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 December 2018 in Journal of the South African Veterinary Association
Verified
Journal Article
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GNGervais Ndazigaruye
Gervais Ndazigaruye
BMBorden Mushonga
Borden Mushonga
EKErick Kandiwa
Erick Kandiwa
ASAlaster Samkange
Alaster Samkange
BSBasiamisi E. Segwagwe
Basiamisi E. Segwagwe
A survey involving 120 small-scale dairy farmers was carried out to assess risk factors associated with brucellosis in cattle from selected sectors of Nyagatare District, Rwanda. A sample of cattle from nine selected sectors of Nyagatare was tested for brucellosis using the Rose Bengal Test. Of the respondents, 57.5% were unaware of brucellosis as a disease, 85.8% did not screen new additions to the herd for brucellosis and 82.5% did not remove brucellosis seropositive animals from the herd. The prevalence of brucellosis in herds with cows with no history of abortion was 38.5% and 17.0% in those with a history of abortion. None of the respondents disinfected abortion sites or vaccinated against brucellosis. The prevalence of brucellosis in cows with a history of retained placenta was 36% and 2% in those with no history of retained placenta. Of the respondents, 62.5% reportedly fed foetal membranes to dogs. About 65.8% of the respondents with brucellosis-positive animals reported a calving interval longer than 1 year. Katabagemu (28.6%) had the highest prevalence of brucellosis seropositivity while Karama had none. Brucellosis in cows (21.4%) was significantly higher than that in heifers (12.8%) (p 0.05), but there was no significant difference between heifers and bulls or between bulls and cows (p 0.05). The occurrence of brucellosis in herds with 40–70 cattle (26.9%) was significantly greater than the 14.9% of herds with 10–39 cattle (p 0.05). Seropositivity to brucellosis in cross-breed cattle (23.6%) was significantly greater than that in indigenous cattle (13.8%) (p 0.05). There was no significant difference in the overall prevalence of brucellosis in cattle from different grazing systems (p 0.05). Seropositivity to brucellosis was significantly different (p 0.05) between the fourth parity (32.5%) and first parity (14.3%) cows. The findings in this study confirmed the existence of brucellosis as a problem in Nyagatare and the authors recommend that farmer education on the epidemiology, risk factors and mitigation of the disease be undertaken as a matter of urgency.

6 September 2018 in Journal of Veterinary Medicine
Verified
Journal Article
Open access
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BMBorden Mushonga
Borden Mushonga
DHDismas Habumugisha
Dismas Habumugisha
EKErick Kandiwa
Erick Kandiwa
OMOscar Madzingira
Oscar Madzingira
ASAlaster Samkange
Alaster Samkange
IJIshmael Festus Jaja
Ishmael Festus Jaja
This study investigated the overall prevalence of Haemonchus contortus infection in sheep and goats from five purposively selected subdivisions (sectors) of Nyagatare district from January to December 2014, after a high prevalence of gastrointestinal parasites and generalized poor productivity was reported in small ruminants in some districts of Rwanda. Faecal egg counts (FEC) were performed using the Modified Wisconsin Sugar Floatation method and the Fluorescent-labeled peanut-lectin agglutination test while enumerations, as log (FEC), were done using the modified McMaster method. The overall prevalence of H. contortus infection in sheep and goats was 75.7% (n=949). The overall prevalence of H. contortus infection in sheep (83.4%, n=314) was higher than in goats (71.8%, n=635) (Odds Ratio [OR] 1.98, 95% Confidence Interval [CI]: 1.40-2.79, and p≤0.001). The prevalence of H. contortus infection in female goats (74.2%) was higher than in male goats (64.3%) (OR 1.60, 95% CI: 1.09-2.36, and p=0.01). The prevalence of H. contortus infection in goats from Nyagatare was higher than in goats from Matimba (OR 3.25, 95% CI: 1.76-5.99, and p≤0.001) and from Katabagemu (OR 3.67, 95% CI: 2.04-6.59, and p≤0.001). The prevalence of H. contortus infection in goats from Karangazi was higher than in goats from Matimba (OR 4.72, 95% CI: 2.40-9.28, and p≤0.001). The overall mean monthly log (FEC) for H. contortus in sheep and goats were highest in April (18.9±0.2 and 14.05±0.1, respectively) and October (19.25± 0.2 and 13.75±0.1, respectively). Though, overall, sheep in Nyagatare district were at greater risk of H. contortus infection and goats from Nyagatare and Karangazi sectors were paradoxically at greater risk of H. contortus infection. It was also apparent that young female goats were at greater risk of H. contortus infection than young male goats. H. contortus infection is endemic in small ruminants in Nyagatare district and possibly other districts in Rwanda. Targeted selective treatment (TST) using FAMACHA with emphasis on low-lying swampy pastures and appropriate anthelmintic drugs may be the most economically viable solution in the short term. In the long term breeding of H. contortus resistant small ruminants and strategic grazing using the concept of refugia may bring about considerable relief from H. contortus infection in Nyagatare district, in particular, and Rwanda at large.

22 May 2019 in Advances in Agriculture
Verified
Journal Article
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BMBorden Mushonga
Borden Mushonga
LHLandouard Hategekimana
Landouard Hategekimana
Gervais HabarugiraGervais Habarugira
Gervais Habarugira
EKErick Kandiwa
Erick Kandiwa
ASAlaster Samkange
Alaster Samkange
BSBasiamisi Victor Ernest Segwagwe
Basiamisi Victor Ernest Segwagwe
A survey was undertaken to characterize the honey production value chain and identify the challenges, limitations, and opportunities for beekeepers in Kayonza District, Eastern Rwanda, in light of the stagnation of the apiculture industry. The majority (86%, n = 100) of the beekeepers were adult males. Most of the respondents (71%) lacked primary level education. The majority of the hives were made from hollow tree logs (40%), tree barks (12%), banana leaves/bark (11%), cow dung (8%), mud (7%), grass (6%), tree leaves (6%), and the rest (20%) were improved beehives, particularly Langstroth hives. The hive pests encountered were hive beetles (25%), small black ants (19%), wax moths (12%), lizards (8%), termites (7%), birds (6%), mites (3%), and mice (2%). Fifty-five percent of the respondents hung their hives on trees to prevent pest invasion with 95% effectiveness, 25% frequently smoked their hives with 85% effectiveness, 16% cleared the bushes around apiaries with 55% effectiveness, and 4% used traditional plant insect repellents with 35% effectiveness. Forty-one percent of the respondents lacked adequate information on beekeeping, 25% had inadequate time to work on apiaries, 24% had inadequate technical knowledge and implements, and 10% needed additional labour for managing apiaries. Based on the results of this study, beekeeping in Kayonza is still largely traditional, characterized by the use of antiquated production methods and underutilization of available marketing channels. Perceptions in the district are that beekeeping is for the poor and illiterate. Challenges and limitations of beekeeping in Kayonza District include lack of education, gender bias, pests and diseases, absconding and swarming of bees, high costs, and lack of modern apicultural equipment. However, the potential for developing beekeeping enterprise (opportunities) is immense given the abundance of wild bee populations, possibility of women participation, abundance of honey collection centres (market), and availability of technical support from Government and development agencies. In conclusion, this study advocates the need for intervention measures to educate and promote production and marketing of quality honey, tackle pest and disease for beekeepers and boost Rwanda’s apiculture industry.

25 May 2020 in Tropical Animal Health and Production
Verified
Journal Article
Closed access
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EKErick Kandiwa
Erick Kandiwa
UNUtjiuasane Nguarambuka
Utjiuasane Nguarambuka
FCFrank Chitate
Frank Chitate
ASAlaster Samkange
Alaster Samkange
OMOscar Madzingira
Oscar Madzingira
BMBorden Mushonga
Borden Mushonga

24 October 2018 in Journal of Toxicology
Verified
Journal Article
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EKErick Kandiwa
Erick Kandiwa
BMBorden Mushonga
Borden Mushonga
ASAlaster Samkange
Alaster Samkange
EFEzequiel Fabiano
Ezequiel Fabiano
This study was designed to investigate the cytotoxicity and haemotoxicity of the Western barred (zebra) spitting cobra (Naja nigricincta nigricincta) venom to help explain atypical and inconsistent reports on syndromes by Namibian physicians treating victims of human ophidian accidents. Freeze-dried venom milked from adult zebra snakes was dissolved in phosphate buffered saline (PBS) for use in this study. Haemorrhagic and necrotic activity of venom were studied in New Zealand albino rabbits. Oedema-forming activity was investigated in 10-day-old Cobb500 broiler chicks. Procoagulant and thrombolytic activity was investigated in adult Kalahari red goat blood in vitro. The rabbit skin minimum hemorrhagic dose (MHD) for N. n. nigricincta was 9.8μg. The minimum necrotizing dose (MND) for N. n. nigricincta venom was 12.2μg. The N. n. nigricincta venom showed linear dose-dependent procoagulant activity on goat blood (p<0.05). Likewise, N. n. nigricincta venom showed linear dose-dependent thrombolytic activity on goat blood (p<0.05, n = 6). Subplantar injection of N. n. nigricincta venom (25μg, 50μg, 75μg, and 100μg) into chick paw resulted in peak oedema of 35.5%, 38.5%, 42.9%, and 47.5%, respectively, two hours after injection. Paw oedema subsided within five hours to a mean volume ranging from 5% (25μg venom) to 17.6% (100μg venom). In conclusion, though N. n. nigricincta belongs to the genus Elapidae, the current study has shown its venom to possess potent hemorrhagic, necrotic (cytotoxic), and paradoxically, both procoagulant and thrombolytic activity. The authors propose further work to fractionate, isolate, and elucidate the structure of the various N. n. nigricincta venom toxins as a prelude to the development of an antivenom.

15 October 2022 in Tropical Animal Health and Production
Verified
Journal Article
Closed access
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ASAlaster Samkange
Alaster Samkange
JWJolandie van der Westhuizen
Jolandie van der Westhuizen
AVAnselm Siegfried Voigts
Anselm Siegfried Voigts
FCFrank Chitate
Frank Chitate
IKIsrael Kaatura
Israel Kaatura
BMBorden Mushonga
Borden Mushonga