Prevalence and vector distributions of bovine trypanosomosis in control (Sibu Sire) and noncontrol (Guto Gida) districts bordering upper Anger valley of East Wollega Zone, Western Ethiopia

A cross-sectional study was conducted from December 2008 to March 2009 in two districts where tsetse control implemented (Sibu Sire district) and non-control implemented (Guto Gida district) bordering Anger river valley in East Wollega Zone, Western Ethiopia. The objectives of the study were to determine the prevalence of bovine trypanosomosis and to assess the distribution and apparent densities of vectors of the trypanosomosis. A parasitological study using buffy coat technique was employed for the determination of prevalence of trypanosomosis while monoconical traps were used for the vector studies. A total of 368 cattle randomly selected from the study population (166 in Sibu Sire and 202 in Guto Gida) districts were examined for the parasitological study. The result of parasitological study revealed that the prevalence of trypanosomosis was found to be 5.42% and 11.88% in Sibu Sire and Guto Gida districts, respectively. There was statistically significant difference in the prevalence of trypanosomosis between tsetse control implemented and non-control implemented districts (

Study on the prevalence of donkey trypanosomosis in Awi zone northwest Ethiopia

The study on trypanosomosis of donkeys was conducted from October 2009 to March 2010 in four districts of Awi zone including Jawi district of tsetse infested, Abadera and Chara districts found at the edge of tsetse infested area and Dangla of tsetse free district. A total of 384 randomly selected donkeys (86 from Abadera, 87 from Chara, 94 from Dangla and 117 from Jawi) were sampled and examined using haematocrit centrifugation technique. The overall prevalence of trypanosomosis of donkeys was 1.6% (n=6). The observed prevalence was not significantly (P > 0.05) different among the four districts. Trypanosoma vivax (75%) and Trypanosoma congolense (25%) were the most common trypanosome species encountered during the study period. No significance difference was observed between male and female donkeys both in prevalence of infection and mean PCV (P > 0.05). The mean PCV of infected donkey (23.50 ± 3.782) was significantly (P < 0.05) lower than that of non infected donkeys (34.70 ± 4.44). The body condition score of the donkey was significantly associated with both prevalence of infection and mean PCV (P < 0.05). The study revealed that trypanosomosis in donkeys in the study areas indicates the presence of both cyclical and non-cyclical transmitted trypanosomes which require inclusion of equines in the control program of trypanosomosis in the study areas

Epidemiology of gastrointestinal helminthiasis of small ruminants in selected sites of North Gondar zone, Northwest Ethiopia

A cross-sectional study was conducted to determine the prevalence and risk factors associated with small ruminant helminthiasis in north Gondar zone, northwest Ethiopia from November-January, 2008. A total of 558 small ruminants (458 sheep and 100 goats) were examined using standard parasitological procedure. The study revealed that the overall prevalence of helminthiasis was 47.67%. The species level prevalence of helminthiasis was 46.07% and 55% in sheep and goats respectively. Strongyles were the most prevalent parasites encountered in the area followed by Fasciola. A statistically significant difference was found in prevalence between sheep and goat. Agroecology was found to be associated with prevalence rate and species of parasite found. Sex and age of the animals were shown to have association with prevalence but significant difference was not found. Therefore during the control and treatment of small ruminant helminthiasis agroecology, species, age and sex of the animals should be considered as potential risk factors for the occurrence of the disease in the study areas

A cross-sectional study on bovine trypanosomosis in Jawi district of Amhara Region, Northwest Ethiopia

A cross-sectional study was carried out from December 2008 to March 2009 in Jawi district of Amhara Regional State northwest Ethiopia to assess the prevalence of bovine trypanosomosis. Blood sample was collected randomly from a total of 300 cattle through piercing of the marginal ear vein to determine the prevalence and measure PCV values for the assessment of anemia. During sampling age, sex and body condition of the animals were recorded to infer risk factors for the occurrence of the disease. The buffy coat technique was em ployed for the detection of trypanosome and to measure PCV values. Thin blood smear was made from positive samples for species identification of the parasite. The prevalence of trypanosomosis was found to be 11.33% (95% CI: 0.08 - 0.15%) in Jawi district of which higher prevalence with species of trypanosome was detected to be for T. congolense (65%) than T. vivax (35%). The prevalence showed no significant difference in susceptibility between sex categories and in age groups. The infection rate between body condition score in parasitaemic and aparasitaemic animals was significantly different (P< 0.05) that poor body conditioned animals were more affected by trypanosomes than good conditioned animals. The mean PCV values in parasitaemic animals was 24.29% +5.58SD while in aparasitaemic animals 27.46% +5.67SD with a statistical significant difference (

Comparative clinico-pathological observations in young Zebu (Bos indicus) cattle experimentally infected with Trypanosoma vivax isolates from tsetse infested and non-tsetse infested areas of Northwest Ethiopia

BACKGROUND: The Northwest region of Ethiopia is affected by both tsetse and non-tsetse transmitted trypanosomosis with a huge impact on livestock productivity. The objective of this experimental study was to determine clinical and pathological findings in young Zebu cattle experimentally infected with Trypanosoma vivax isolates from tsetse infested and non-tsetse infested areas of Northwest Ethiopia. A total of 18 cattle (Bos indicus) aged between 6 and 12 months, purchased from a trypanosome-free and confirmed to be trypanosome negative divided into three groups of six animals were used. Animals in the first two groups (Group TT: tsetse infested isolate infected and Group NT: non-tsetse infested isolate infected) received 2 mL of infected blood from donor animals at 10(6) trypanosomes/mL, and the remaining group was non-infected control (NIC). Each group was observed for a period of eight consecutive weeks, daily for clinical signs and once per week for parasitaemia. Postmortem examinations were done on euthanized animals, and tissue samples were taken for histopathological analysis. RESULTS: The prepatent period of the disease was earlier in the NT group 6 days post infection (dpi) than TT group 12 dpi. The infection was characterized by reduced feed intake, intermittent pyrexia and parasitaemia, enlarged lymph nodes, lacrimation, reduced feed intake and emaciation. Less frequently diarrhea, oedema and nervous signs were observed in both groups of infected animals. At necropsy, infected animals showed enlarged spleen, enlarged lymph nodes, pneumonic and emphysematous lung, enlarged liver, and haemorrhages on the brain and intestine. Histopathological analysis revealed lymphoid hyperplasia of the spleen, necrosis of the liver, encephalitis and hyperplasia of lymph nodes. CONCLUSION: Trpanosoma vivax isolates from both tsetse infested and non-tsetse areas showed a variety of virulence factors leading to the development of acute clinical signs, gross and histopathological lesions. However, the parasitaemia and clinical signs appeared earlier in the NT compared to TT infected groups

Grazing season and forage type influence goat milk composition and rennet coagulation properties

Two different types of pasture (cultivated and rangeland) and 2 different hay qualities (high and low quality) were examined for their effects on goat milk composition and rennet coagulation properties. Furthermore, the effect of dietary treatments in both the early and late grazing season was studied. As lactation stage is known to influence milk composition, the goats in the early and late grazing season were in the same lactation stage at the start of the experiment. The milk composition was influenced both by dietary treatment and season. Milk from goats on pasture was superior to those on hay by containing a higher content of protein and casein, and the goats on cultivated pasture had the highest milk yield. Casein composition was significantly influenced by forage treatment. Goats grazing on cultivated pasture had higher contents of αs1-casein and also of κ-casein compared with the other treatments, whereas goats grazing on rangeland had the highest content of β-casein. Factors such as milk yield, casein micelle size, αs2-casein, and calcium content were reduced in late compared with early season. More favorable rennet coagulation properties were achieved in milk from the early grazing season, with shorter firming time and higher curd firmness compared with milk from the late grazing season, but the firming time and curd firmness were not prominently influenced by forage treatment. The content of αs2-casein and calcium in the milk affected the firming time and the curd firmness positively. The influence of season and forage treatment on especially milk yield, casein content, and rennet coagulation properties is of economic importance for both the dairy industry and goat milk farmers

Predicting dry matter intake in Canadian Holstein dairy cattle using milk mid-infrared reflectance spectroscopy and other commonly available predictors via artificial neural networks.

Dry matter intake (DMI) is a fundamental component of the animal's feed efficiency, but measuring DMI of individual cows is expensive. Mid-infrared reflectance spectroscopy (MIRS) on milk samples could be an inexpensive alternative to predict DMI. The objectives of this study were (1) to assess if milk MIRS data could improve DMI predictions of Canadian Holstein cows using artificial neural networks (ANN); (2) to investigate the ability of different ANN architectures to predict unobserved DMI; and (3) to validate the robustness of developed prediction models. A total of 7,398 milk samples from 509 dairy cows distributed over Canada, Denmark, and the United States were analyzed. Data from Denmark and the United States were used to increase the training data size and variability to improve the generalization of the prediction models over the lactation. For each milk spectra record, the corresponding weekly average DMI (kg/d), test-day milk yield (MY, kg/d), fat yield (FY, g/d), and protein yield (PY, g/d), metabolic body weight (MBW), age at calving, year of calving, season of calving, days in milk, lactation number, country, and herd were available. The weekly average DMI was predicted with various ANN architectures using 7 predictor sets, which were created by different combinations MY, FY, PY, MBW, and MIRS data. All predictor sets also included age of calving and days in milk. In addition, the classification effects of season of calving, country, and lactation number were included in all models. The explored ANN architectures consisted of 3 training algorithms (Bayesian regularization, Levenberg-Marquardt, and scaled conjugate gradient), 2 types of activation functions (hyperbolic tangent and linear), and from 1 to 10 neurons in hidden layers). In addition, partial least squares regression was also applied to predict the DMI. Models were compared using cross-validation based on leaving out 10% of records (validation A) and leaving out 10% of cows (validation B). Superior fitting statistics of models comprising MIRS information compared with the models fitting milk, fat and protein yields suggest that other unknown milk components may help explain variation in weekly average DMI. For instance, using MY, FY, PY, and MBW as predictor variables produced a predictive accuracy (r) ranging from 0.510 to 0.652 across ANN models and validation sets. Using MIRS together with MY, FY, PY, and MBW as predictors resulted in improved fitting (r = 0.679-0.777). Including MIRS data improved the weekly average DMI prediction of Canadian Holstein cows, but it seems that MIRS predicts DMI mostly through its association with milk production traits and its utility to estimate a measure of feed efficiency that accounts for the level of production, such as residual feed intake, might be limited and needs further investigation. The better predictive ability of nonlinear ANN compared with linear ANN and partial least squares regression indicated possible nonlinear relationships between weekly average DMI and the predictor variables. In general, ANN using Bayesian regularization and scaled conjugate gradient training algorithms yielded slightly better weekly average DMI predictions compared with ANN using the Levenberg-Marquardt training algorithm

Effects of Incorporating Dry Matter Intake and Residual Feed Intake into a Selection Index for Dairy Cattle Using Deterministic Modeling.

The inclusion of feed efficiency in the breeding goal for dairy cattle has been discussed for many years. The effects of incorporating feed efficiency into a selection index were assessed by indirect selection (dry matter intake) and direct selection (residual feed intake) using deterministic modeling. Both traits were investigated in three ways: (1) restricting the trait genetic gain to zero, (2) applying negative selection pressure, and (3) applying positive selection pressure. Changes in response to selection from economic and genetic gain perspectives were used to evaluate the impact of including feed efficiency with direct or indirect selection in an index. Improving feed efficiency through direct selection on residual feed intake was the best scenario analyzed, with the highest overall economic response including favorable responses to selection for production and feed efficiency. Over time, the response to selection is cumulative, with the potential for animals to reduce consumption by 0.16 kg to 2.7 kg of dry matter per day while maintaining production. As the selection pressure increased on residual feed intake, the response to selection for production, health, and fertility traits and body condition score became increasingly less favorable. This work provides insight into the potential long-term effects of selecting for feed efficiency as residual feed intake

Integrating energy access, efficiency and renewable energy policies in Sub-Saharan Africa: a model-based analysis

The role of energy in social and economic development is recognised by sustainable development goal 7 that targets three aspects of energy access: ensure universal access to affordable, reliable and modern energy services, substantially increase the share of renewable energy, and double the global rate of improvement in energy efficiency. With the projected increase in population, income and energy access in Sub-Saharan Africa, demand for energy services is expected to increase. This increase can be met through increasing the supply while at the same time improving households' energy efficiency. In this paper, we explore the interactions between the three SDG7 targets by applying two Integrated Assessment Models, IMAGE and MESSAGE, that incorporate socio-economic heterogeneity of the end-user. The results of the study depict the synergistic relationships between the three SDG7 objectives. Relative to pursuing only the universal access target, integration of all three targets could i) reduce residential final energy consumption by up to 25%, enabling the use of mini-grid and stand-alone systems to provide better energy services, ii) cut annual energy-use-related residential emissions by a third, and iii) lower energy related investments by up to 30% to save scarce finance

Selective advantage of implementing optimal contributions selection and timescales for the convergence of long-term genetic contributions

Additional file 1: Figure S1. Accumulation of long-term genetic contributions over time with a line of best fit