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1.
A Markos A Blah?sková M Kalous E Bysková K Byska E Nohynková 《Folia parasitologica》1989,36(3):225-238
Bloodforms of Trypanosoma brucei brucei STIB 247 taken from rats and containing more than 80 per cent short stumpy forms, differentiated in vitro to procyclic forms in medium SDM 79 (Brun and Sch?nenberger 1979), enriched with 3 mmol.dm-3 cis-aconitate. Cell division was abolished by the addition of hydroxyurea (200 micrograms.ml-1) or arabinosyl adenine (20 micrograms.ml-1 to the cultivation medium, or by the omission of serum from the medium. The ultrastructure of exponentially growing controls was rearranged within 24 h. The endogenous respiration and the respiration stimulated by proline, succinate, and 2-oxoglutarate were detectable within 12 h; after 48 h the respiration rates were comparable to those found in the established procyclic forms. After 12 h the respiration was inhibited by 200 mumol.dm-3 KCN, and by 20 mumol.dm-3 antimycin to the extent found in procyclic forms. Hydroxyurea did not significantly affect respiration. Activities of procyclic-stage enzyme markers malate dehydrogenase, threonine dehydrogenase, succinate: cytochrome c reductase, and NADH: cytochrome c reductase rose within 48 h of differentiation to values which were close to those found in established procyclic forms. The activity of glutamate dehydrogenase (NAD-specific), however, was only 1/3 of that in the procyclics, and no citrate synthase was detected in differentiating culture. Glycosomal malate dehydrogenase was detected after 6 h. In the presence of hydroxyurea or arabinosyl adenine, or in the absence of serum, respiration rates, marker enzyme activities, and glycosomal malate dehydrogenase developed to the extent comparable to the untreated controls. The results suggest that it is possible to separate the process of differentiation from cell proliferation. Cell division is not a necessary prerequisite of differentiation. 相似文献
2.
An investigation was carried out into an outbreak of respiratory disease complex (RDC) in 3641 Menz and Awassi×Menz cross sheep in Central Ethiopia between 1998 and 1999 by clinical, serological, microbiological, post-mortem and histopathological examinations. The monthly incidence of RDC varied from 2.8% to 4.0% and the prevalence was as high as 17%. The case fatality rate was 18%, despite culling of sick sheep. Over 76% of the morbidity occurred in adults, followed by 19% among weaners. Similarly, 62% of the mortality was in adults. However, 27% of the mortality occurred in lambs despite the low morbidity in the group. Significant breed and age differences were seen in the morbidity and mortality rates (p<0.05). Clinical signs, gross and microscopic lesions and serological and bacteriological examinations showed an interplay of several causes of the RDC, including pestes des petits ruminants (PPR) (72.3%, serologically confirmed), lung worms, maedi-visna, bacterial bronchopneumonia (staphylococcal and streptococcal), enzootic pneumonia and some fungal infections. Cold temperatures, which may be as low as –8.5°C at night, are major predisposing factors along with managemental stresses. Vaccination of animals with a homologous PPR vaccine appeared to decrease dramatically the occurrence of the disease, showing that PPR played an important role in the outbreak. Several of the pathogens do not appear to be individually capable of causing the respiratory disease. Appropriate strategies for the prevention of RDC are suggested. 相似文献
3.
Hibret A Toé F Mukasa-Mugerwa E Kassa T Markos T 《Tropical animal health and production》2001,33(3):219-227
Clinical examination, bodily condition score (BCS), heart girth (HG), body length (BL), wither height (WH), and scrotal circumference (SC) were assessed on 486 mature Ethiopian Menz rams, on small farms, in local markets, and at the main abattoir in Addis Ababa from December 1994 to April 1995. Almost 27% of the rams were found to be unfit for breeding. Poor general condition, mainly in the form of respiratory disorders, was seen in 1.2% of the rams. Balanoposthitis, epididymitis and orchitis were the most common pathological conditions, affecting the external reproductive organs in 14.6%, 4.5% and 4.1% of the rams, respectively. Testicular calcification, cysts and testicular haemorrhagic lesions were detected in 4, 6 and 8, respectively, of the 60 rams examined at necropsy. The BCS, HG, BL and WH averaged 2.1±0.5, 67.7±5.0 cm, 60.1±4.5 cm and 60.1±4.3 cm, respectively. The mean SC was 25.5±3.9 cm and did not vary significantly with age (p>0.05). Among the linear body measurements, the highest correlation was between BL and WH (r = 0.66). SC was found to be most closely correlated to HG (r = 0.46). More investigations into the relationship between the present findings and actual fertility, and on their practical application in the selection of rams for breeding is recommended. 相似文献
4.
Palya V Nagy M Glávits R Ivanics E Szalay D Dán A Süveges T Markos B Harrach B 《Acta veterinaria Hungarica》2007,55(1):135-149
Epidemiological, pathological, serological and virological investigations are reported on turkey haemorrhagic enteritis virus (THEV) infection in Hungarian turkey flocks. The pathogenesis of infection in experimentally infected turkeys and chickens, as well as the usefulness of polymerase chain reaction (PCR)/sequencing method for epidemiological investigation and for the differentiation of vaccine and field strains of THEV was also studied. Since the first recognition of the disease in Hungary in the late 1970s, until recently the disease has been diagnosed sporadically in its mild form. In the last few years (2000-2005), however, the number of outbreaks and the severity of the disease increased (9-23 affected flocks/year). Most of the outbreaks occurred at the age of 6 to 8 weeks and was complicated with Escherichia coli infection. The antibody levels to THEV in turkey flocks gradually declined till 5-7 weeks of age, and then they increased sharply due to natural infection with THEV. The immune response to vaccination (at 5 weeks of age) showed no significant antibody level increase one week postvaccination, but four weeks later the antibody level reached high values and then remained at this high level. The agar gel immunodiffusion (AGID) test to detect turkey adenovirus A (TAdV-A) antigen and PCR methods for THEV-specific DNA gave similarly positive results if spleens with pathognomonic lesions were tested; however, PCR proved to be more sensitive in cases with less characteristic pathological lesions. Nucleotide sequence alignment of PCR products amplified from Hungarian field strains and the Domermuth vaccine strain and that of the published THEV hexon sequences in GenBank database revealed slight differences between the sequences. 相似文献
5.
Mengistie Taye Girma Abebe Solomon Gizaw Sisay Lemma Abebe Mekoya Markos Tibbo 《Tropical animal health and production》2010,42(4):659-667
A study was conducted to evaluate growth performances of Washera sheep under smallholder production systems in the Yilmanadensa
and Quarit districts of the Amhara National Regional State, Ethiopia. Data were collected and analysed on the growth of 690
lambs owned by 110 households from October 2004 to September 2007. Weight (kilograms) of Washera lambs at birth, 1, 3, 6,
9 and 12 months of age was 2.69 ± 0.02, 7.10 ± 0.16, 12.42 ± 0.11, 16.12 ± 0.91, 20.05 ± 0.55 and 23.47 ± 0.68, respectively.
Birth weight was significantly (P < 0.05) affected by district, year of birth, parity of the dam, birth type and sex of lamb and by the interaction effect
of parity by birth type and parity by sex of lamb. Weaning weight was also affected by year of birth, type of birth and sex
of lamb. Yearling weight was affected by only year of birth and sex of birth. The average daily weight gain (ADG; grams) from
birth to 30 days, birth to 90 days, 90 to 180 days and birth to 1 year of age was 143.37 ± 13.46, 107.09 ± 2.67, 39.78 ± 9.73
and 60.13 ± 1.89, respectively. Growth rates from birth to 30 and 90 days of age were significantly (P < 0.05) affected by birth year, birth type and sex. ADG from birth to 1 year of age was affected by lamb sex and district.
The indigenous Washera sheep had faster growth rate than those sheep breeds of Ethiopia extensively studied thus far. Integrated
efforts combining improved nutrition, health and participatory community-based breeding would help the smallholder farmers
to utilise and conserve this immense sheep genetic resource of Ethiopia. 相似文献
6.
Bloodforms of Trypanosoma brucei brucei (STIB 247) differentiated in vitro into procyclic forms as described in the accompanying paper (Markos et al. 1989). The importance of the respiratory chain for the process was tested by the inhibition of its development (omission of hemin from the medium) or function (respiratory inhibitors). In the absence of hemin, all enzyme markers of the procyclic state, except for hemoproteins, developed to 50-70 per cent of control values. The presence of hemin is therefore not essential for the onset of differentiation, although the process cannot be completed under hemin limitation. Addition of 1 mumole.dm-3 KCN, 10 mumole.dm-3 antimycin A, or 100 mumole.dm-3 salicyl hydroxamate (SHAM) did not block the differentiation, although it proceeded at a slower rate. The development of the inner mitochondrial membrane markers--succinate: cytochrome c reductase, and NADH: cytochrome c reductase--was strongly inhibited by KCN or antimycin. None of these inhibitors had a significant effect on the activity of procyclic state marker--glycosomal malate dehydrogenase. 相似文献
7.
Aregu Amsalu Aserse Daniel Markos Genet Getachew Markku Yli-Halla Kristina Lindström 《Archives of Agronomy and Soil Science》2020,66(4):488-501
ABSTRACTWhile pulses are staple food-legumes in Ethiopia, their productivity is low due to low soil fertility. Elite rhizobial strains that significantly increased shoot dry weight and nitrogen (N) contents of common beans and soybeans in greenhouse were selected for two-year field trials to evaluate their effect on yields of the pulses in the field. Each pulse had six treatments, namely four rhizobial inoculants, uninoculated control, and synthetic N fertilizer. In the drought-affected year 2015, inoculated pulses tolerated moisture stress better than non-inoculated controls. Inoculation was conducive to higher or equivalent yields compared to synthetic N fertilizer. At Halaba, bean inoculated with strain HAMBI3562 gave the highest grain yield (1500 ± 81 kg ha?1; mean±SE) while the control yielded only 653 ± 22 kg ha?1. At Boricha, HAMBI3570 gave a grain yield (640 ± 35 kg ha?1) comparable to synthetic N. When rainfall was optimal in 2016, inoculation with HAMBI3562 and HAMBI3570 gave grain yields (around 4300 kg ha?1) equivalent to synthetic N. With soybean, strain HAMBI3513 produced consistently higher or comparable biomass and grain yields compared to synthetic N. In conclusion, HAMBI3562 and HAMBI3570 for beans and HAMBI3513 for soybeans can serve as inoculants for areas having similar conditions as the test areas. 相似文献
8.
9.
Achenef M. Markos T. Feseha G. Hibret A. Tembely S. 《Tropical animal health and production》1999,31(1):15-24
An investigation was carried out at Debre Berhan, Ethiopia, between 1996 and 1997, into the epidemiology of coenurosis in Menz and Horro breeds of sheep. A total of 37 heads from clinically sick and 183 heads from apparently healthy sheep were examined post mortem for the presence of the cystic larvae of Taenia multiceps, of which 37 and 5 heads, respectively, contained 1 to 8 coenurus cysts (diameter 0.8 to 6.5 cm). The bladder worms were located in the cerebral hemisphere in 96% of the cases (43% and 57% for left and right, respectively), 4% being in the cerebellum. Prediction of cyst locations based on the direction of circling and head deviation had a 62% success rate. A retrospective study generated from the health record book at the ILRI Debre Berhan Station in 1992–1996 (199 Horro and 174 Menz) revealed that the incidence of coenurosis ranged from 2.3% to 4.5%. There was no significant breed difference in the incidence. The age of the affected sheep ranged from 4 to 96 months, with a mean of 19.3 months, and 72% of the cases were within the range of 6 to 24 months. In a complementary survey on necropsied stray dogs, 8 out of 17 were positive for Taenia spp. Both studies confirm the endemicity of coenurosis at the ILRI Debre Berhan Research Station. Appropriate strategies for the control of coenurosis are suggested. 相似文献
10.
Aynalem Haile Abebaw Gashaw Taye Tolemariam Markos Tibbo 《Tropical animal health and production》2010,42(5):825-831
An investigation was made into the epidemiology of nematode infections of sheep in two districts of Jimma zone, southwestern
Ethiopia. We used two approaches—long-term monitoring of identified sheep for nematode infection and abattoir or market survey
for analysis. In the first monitoring regime, we used 80 lambs [40 sheep (20 per sex) from each district (Dedo and Yebu)]
averaging 4–5 months of age. Faecal egg counts (FEC), packed cell volume (PCV) and body weight changes were monitored over
a period of 1 year. Additionally, faecal samples were collected (on a weekly basis) from sheep brought to abattoir/market
for 1 year to monitor faecal egg counts. The nematode parasite burden, as judged by FEC and PCV, was generally low indicating
that the climatic conditions are not conducive to the development and survival of nematode eggs and the free-living stages;
hence, little transmission occurred. In the experimental flocks, the highest FEC and lower PCV were recorded during the long
rainy season (June to September) with peak in August and September. Faecal samples collected from abattoir/market also followed
the same trend. Results from experimental sheep indicated that location had a significant (P < 0.01) effect on FEC, PCV and average daily body weight gain. The FEC and PCV for sheep in Yebu (mid-altitude) district
were 126 ± 3.33 and 30.6 ± 0.26, whereas the values for Dedo (highland) were 93 ± 4.35 and 32.0 ± 0.21, respectively. The
results indicate that the highland areas are comparatively less favourable to the survival and development of nematodes. Female
lambs had lower FEC and higher PCV compared to male lambs (P < 0.05). The overall nematode parasite challenge in the area, however, is low. We, therefore, recommend rotational grazing
management combined with monitoring parasite load and selective treatment to reduce productivity loses and pasture contamination. 相似文献