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1.
P. Chatikobo T. Choga C. Ncube J. Muzenda-Mutambara 《Tropical animal health and production》2009,41(7):1289-1297
To determine the current distribution of bovine dermatophilosis in Zimbabwe, participatory rural appraisals were held at 36
locations in six districts. Results showed that bovine dermatophilosis is no longer confined to Hwange-Lupane area, but is
now endemic in Gokwe, Sanyati, Kwekwe, and Kadoma. Virgin outbreaks of the disease were preceded by the appearance of Amblyomma
variegatum ticks within an area. Spreading to new geographical areas (cited above) occurred during the liberation struggle
(1975/79), droughts (1992/93, 1995/96), and of late, the land re-distribution exercise (2000–2002). Immediately after the
war (1980/82), both the ticks and the disease were first cited in Gokwe whereas prior to that (1922–1980), both were confined
to Hwange-Lupane area in the northwestern parts of Zimbabwe. Transmission from Gokwe to Sanyati, and from Sanyati to Chenjiri,
occurred during the droughts of 1992/93 and 1995/96 respectively. In all the cases, the spreading of dermatophilosis was secondary
to reduced tick control on cattle. The presence of dermatophilosis in the highveld (Kwekwe, Kadoma), a prime cattle production
zone for the country, is a major threat to livestock production. These results have policy implications for tick and tick-associated
diseases (dermatophilosis) control strategies for Zimbabwe. 相似文献
2.
Ncube Sharai Saidi Petronella Tapiwa Tivapasi Musavengana Tapera Imbayarwo-Chikosi Venancio Edward Halimani Tinyiko Edward 《Tropical animal health and production》2018,50(3):665-670
Tropical Animal Health and Production - The objective of the study was to determine serum lipid, enzyme, and hematological responses of broilers to Acacia angustissima leaf meal. Acacia... 相似文献
3.
Katsande TC More SJ Bock RE Mabikacheche L Molloy JB Ncube C 《The Onderstepoort journal of veterinary research》1999,66(4):255-263
The geographical distribution of Babesia bovis and Babesia bigemina antibodies in communal herds in northern and eastern Zimbabwe was determined using the ELISA technique. The animals in different herds in the study region had different levels of natural exposure to B. bovis (mean 32%, range 0-79%) and B. bigemina (mean 52%, range 5-92%) infections. The majority of herds (90%) were endemically unstable for B. bigemina and 62% were unstable for B. bovis. Natural region 5 and Manicaland province had the highest seroprevalence of B. bovis infection, while natural region 5 and Masvingo province had the highest seroprevalence of B. bigemina infection. 相似文献
4.
B. Ncube S. J. Twomlow J. P. Dimes M. T.
Van Wijk K. E. Giller 《Soil Use and Management》2009,25(1):78-90
Poor soil fertility and erratic rains are major constraints to crop production in semi‐arid environments. In the smallholder farming systems of sub‐Saharan Africa, these constraints are manifested in frequent crop failures and endemic food insecurity. We characterized a semi‐arid smallholder farming system in south‐western Zimbabwe to assess crop production, nutrient use and factors that constrain productivity. The farming system was studied using resource flow mapping, farmer interviews and calculations of crop production over three cropping seasons (2002/2003, 2003/2004 and 2004/2005) to capture variability between years. Farmers were categorized into three groups: better resourced, medium resourced and poorly resourced. Better resourced farmers produced adequate grain for basic household consumption, except in the drought year (2002/2003). Poorly resourced farmers had large grain deficits, whereas the medium resourced class had smaller deficits. Better resourced and medium resourced farmers produced adequate amounts of staple cereal in two of the seasons, while poorly resourced farmers produced inadequate amounts of food in all three seasons. All farmers produced less than 300 kg/ha of legumes per season. Lack of seed was cited as the main reason for poor legume production. Better resourced farmers used animal manure (2000–5000 kg per season) and some fertilizer on their cereal crops, while the medium resourced group used less manure (1000 kg or less) and no fertilizer. The use of manure varied strongly across the years. Poorly resourced farmers used no nutrient inputs on any of their crops. All groups had negative nitrogen balances during the three cropping seasons, although the values varied strongly between seasons. Investigation of the potential strategies for developing sustainable production systems are required to address the problems of food security in the semi‐arid parts of the country and the region. 相似文献
5.
6.
We compared the chemical composition of wood fibres and fibre surfaces of several eucalypt species and hybrids originating
from various growth sites in South Africa. The objective was to test for differences in chemical surface composition due to
genetics or site with the ultimate aim to facilitate a tailor-made supply of wood for pulping that results in an optimal blend
of fibres that can be pulped together with similar yields. This, however, requires a sound knowledge of the fibre properties.
The surface functionality on the single fibre level is a key property, because it determines how good inter-fibre bonding
will be when paper is formed, which depends amongst other fibre properties on the amount of free hydroxyl groups that are
available and therefore on the cellulose content on the fibre surface. The cellulose and lignin content on the fibre surface
were determined with chemical force microscopy, a variation of atomic force microscopy. Since the general bulk composition
of the fibre and the surface composition might differ, both parameters were determined. We found significant differences in
the cellulose and lignin content on fibre surfaces, with regard to genotype and site, respectively. In some, but not all,
cases, the surface composition of wood fibres followed the bulk composition, and differences were generally more pronounced.
Differences due to genotype were significant, especially with regard to the surface lignin content—but variation due to site
was also distinctly recognisable. This variation in surface functionality could be the reason why some pulpwood blends result
in a lower pulp yield and different quality. 相似文献
7.
A. Schoeman B. C. Flett B. Janse van Rensburg E. Ncube A. Viljoen 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(3):677-688
Sunflower (Helianthus annuus L.) is an important oilseed crop in South Africa, and is grown in rotation with maize in some parts of North West, Limpopo, Free State, Mpumalanga and Gauteng provinces. Alternaria leaf blight is currently one of the major potential disease threats of sunflower and is capable of causing yield losses in all production regions. Alternaria helianthi was reported as the main cause of Alternaria leaf blight of sunflower in South Africa; however small-spored Alternaria species have been consistently isolated from leaf blight symptoms during recent surveys. The aim of this study was to use morphological and molecular techniques to identify the causal agent(s) of Alternaria blight isolated from South African sunflower production areas. Alternaria helianthi was not recovered from any of the sunflower lesions or seeds, with only Alternaria alternata retrieved from the symptomatic tissue. Molecular identification based on a combined phylogenetic dataset using the partial internal transcribed spacer regions, RNA polymerase second largest subunit, glyceraldehyde-3-phosphate dehydrogenase, translation elongation factor and Alternaria allergen gene regions was done to support the morphological identification based on the three-dimensional sporulation patterns of Alternaria. Furthermore, this study aimed at evaluating the pathogenicity of the recovered Alternaria isolates and their potential as causal agents of Alternaria leaf blight of sunflower. Pathogenicity tests showed that all the Alternaria alternata isolates tested were capable of causing Alternaria leaf blight of sunflower as seen in the field. This is the first report of A. alternata causing leaf blight of sunflower in South Africa. 相似文献
8.
Prisca H Mugabe Rigison Nyashanu Sharai Ncube Venancio E Imbayarwo-Chikosi Shephard Siziba Barbara V Maasdorp 《African Journal of Range and Forage Science》2016,33(3):173-180
Bagged sole maize and maize–cowpea silages in three bag sizes were assessed at 42 and 282 d post-ensiling for sensory and chemical quality. A survey of dairy farmers on silage use and preferences was conducted in the Chikwaka communal area and Marirangwe small-scale commercial farming area. Only silage dryness changed with time. Percentage neutral detergent fibre significantly changed in 20?kg bags from 58.1 ± 0.75% at 42 d to 52.3 ± 0.86% at 282 d and in 10?kg maize–cowpea bags from 48.6 ± 0.75% to 56.0 ± 0.86%. Percentage crude protein significantly decreased (P < 0.05) for 15?kg (11.8 ± 0.30% to 9.4 ± 0.35%) and 20?kg bags (11.4 ± 0.30% to 8.9 ± 0.35%) for maize– cowpea. All 45 farmers surveyed knew about silage and 90% were feeding it to cows, 53% were making their own and 37% purchased silage. Challenges in making silage included unavailability of forage choppers, lack of requisite resources and inadequate knowledge. Silage unavailability and difficulties in transportation and storage resulted in a low frequency of silage purchases. There was no association (χ2 0.18; P > 0.05) between farming system and farmers’ willingness to buy or sell silage, and larger bags were preferred (χ2 78.96; P < 0.05). Computed silage costs per tonne were farm-produced sole maize US$57.54, maize–cowpea US$58.59 and bought-in sole maize US$89.80. 相似文献
9.
Washaya S. Tavirimirwa B. Dube S. Sisito G. Tambo G. Ncube S. Zhakata X. 《Tropical animal health and production》2019,51(7):1963-1968
A study was conducted to compare conception rates in 71 Tuli and 86 Afrikander beef cattle bred using either artificial insemination (AI) or the bull. Animals were bred using either artificial insemination or natural service at Matopos Research Station. Animals were grouped into three groups of heifers (parity 0; P0), second calvers (parity 1; P1) and mature cows (parity 2; P2) before being randomly assigned to one of the two breeding methods. A binary logistic regression was used for statistical analysis where breeding method (AI vs natural service) was the treatment factor and conception rate was the measured response while breed, parity and last calving date were non-treatment factors. No significant differences were observed in conception rates between breeds (P > 0.05). However, the method of breeding animals, parity and calving interval affected (P < 0.05) conception rates. The breeding method, parity and calving interval had a positive Kendall’s tau-b correlation coefficients to conception. More animals were pregnant when AI (77.6%) was used compared with natural mating (56.79%). Conception rates were significantly lower (P < 0.05) in C1 compared with C2 cattle. The odds ratio for breeding method and parity are positive and significant (P < 0.05). In conclusion, the study confirms that artificial inseminated animals had similar conception rates to naturally serviced animals for both Tuli and Afrikander breeds. As such, artificial insemination technology can be used to complement or substitute natural service in indigenous cattle’s of Zimbabwe.
相似文献10.
Bruce Tavirimirwa Emmanuel Manzungu Sharai Ncube Shadreck Ncube Clarice Mudzengi 《African Journal of Range and Forage Science》2019,36(2):73-83
The management of rangelands over the past decade in Zimbabwe has been on the decline. This has resulted in degraded and depleted communal rangelands. A number of recommendations by various government departments, researchers and non-governmental organisations have been implemented. These focused on improving communal grazing areas throughout the country. Notable examples include the livestock destocking policy, introduction of grazing schemes, improved forage grasses, veld legume reinforcement and agro-forestry technology. However, success in improving communal grazing areas has been limited, with forage productivity in communal areas declining, soils still eroding, as well as loss of flora and fauna diversity. The objectives of this paper are to review factors limiting efforts to improve communal grazing areas, constraints to adoption of rangeland technologies necessary to achieve desired plant community for livestock production, and present recommendations to overcome the challenges. The review concludes that there has been limited farmer participation in efforts to improve communal grazing areas and livestock productivity, thus the low adoption of technologies to improve the grazing areas. It is therefore recommended to use participatory approach methodologies to assist communal livestock farmers to improve their grazing areas. 相似文献