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141.
Afshin Raoofi Farhid Hemmatzadeh Amir Mansoor Ghanaei 《Tropical animal health and production》2010,42(3):411-414
This serological survey was carried out to detect antibodies in dromedary camels against BVD virus in Iran. A total of 137
serum samples, were collected from camels at Khorein abattoir in suburbs of Tehran and examined for BVDV, using the serum
neutralization test (SNT). Twenty seven of the 137 camels (19.7%) were positive for BVDV antibodies. It was found that the
rate of seropositive camels in Iran is substantially higher compared to figures published in most other countries. This study
indicated an increased frequency of infection rate with increasing age of camels. The frequency of positive cases was not
significantly different between male and female camels. 相似文献
142.
Luuk B. Schoonman T. Wilsmore Emmanuel S. Swai 《Tropical animal health and production》2010,42(4):579-587
In view of the worldwide importance of Toxoplasma gondii and the fragmented information on the seroprevalence of the disease in animals in Tanzania, a study, using the modified Eiken
latex agglutination test (LAT), was conducted from May 2003 to January 2004 to determine the prevalence of antibody to T. gondii in 130 randomly selected farms comprising 655 cattle. The overall seroprevalence of T.gondii antibodies in cattle and farms were 3.6% and 13%, respectively. Risk factors for animal and herd-level toxoplasmosis seropositivity
were tested using multivariable logistic regression to control for confounding factors. Cattle managed under traditional husbandry
practises were more likely to be seropositive than those managed under smallholder practises (48% versus 4.7%; p < 0.01). Herd size of ≥ 9 cattle were at greater risk of acquiring infection than herds holding fewer animals [≤ 9 cattle],
(odd ratio [OR] = 3.99; 95% confidence interval [CI], 0.97–16.48; P = 0.001). We concluded that seroprevalence at herd level was high and relatively low at animal level, possibly due to the
reduced susceptibility of cattle to T.gondii infection as compared to goats and sheep. The high seroprevalence in animals managed by traditional husbandry practise suggests
that the parasite is widely distributed in the environment and could pose a public health threat to the people living in those
areas. 相似文献
143.
A study was conducted to evaluate the macro and trace mineral contents of ten enset varieties collected from Sidama zone of
southern Ethiopia. Samples of leaf lamina, leaf midrib, pseudostem and corm were taken from ten enset varieties at the age
of 5 to 6 years during the main rainy season. The dry weight of each variety and fraction were also determined. Mineral contents
in fractions of different enset varieties were analysed and compared with nutrient requirements of ruminants. The contribution
of different enset fractions to the total dry weight was variable (P < 0.05), the highest being from pseudostem and the lowest
from leaf lamina. There were varietal differences (P < 0.05) in macro and trace mineral content in different fractions except
phosphorus (P) content of leaf lamina. Most enset fractions were rich sources of major minerals such as P, potassium (K),
calcium (Ca) (except corm) and magnesium (Mg). Sodium (Na) content was very low. Most fractions were rich in iron (Fe) and
manganese (Mn), but deficient in copper (Cu), except leaf lamina. Zinc (Zn) content was high in corm, but low in other fractions.
This account of the macro and trace mineral content of different enset varieties and fractions could help in strategic supplementation
intended to alleviate mineral deficiencies. 相似文献
144.
AGPT and HA tests were employed for rapid diagnosis of PPRV infection in sheep and goats in Sudan. Forty lymph nodes and spleen
samples from suspected cases of PPR in both sheep and goats were examined by AGPT and HA tests for detection of PPRV antigen.
Viral antigen was detected from (77.5%) of the samples tested by AGPT and (92.5%) tested by HA test. The results of both tests
revealed that HA test was more sensitive than AGPT for detection of PPRV antigen (Kappa statistics 0.4366). Another advantage
of the HA test over AGPT was that it can differentiate PPRV from RPV. Thus the HA test represents a quick, easy, simple, cheap
and reliable confirmatory test for the diagnosis of PPR and differential diagnosis of PPRV and RPV. The HA test was carried
out using chicken, goat and pig RBCs. Chicken RBCs were found to be the most sensitive for detection of PPRV antigen, followed
by goat then pig RBCs. The HA time when using chicken RBCs was 20–25 minutes, using goat RBCs was 25–30 minutes and using
pig RBCs was 40–45 minutes. The distribution of PPR infection in four different regions of Sudan was investigated. 相似文献
145.
An ultrastructural study was performed on chloride cells of euryhaline R.r.Caspicus of south of Caspian Sea. The chloride
cells are distributed in the interlamellar region of filaments. They are oval to elongated form with an apical positioned
nucleus, expanded tubular system and heteromorphic mitochondria. These cells are surrounded by pavement cell and accessory
cell. A small and depressed surface formed by pavement cells is in contact with the aquatic milieu. There is also channel
system in accessory cells. One of the typical features was the important changes in microtubules and mitochondria of chloride
cells in some fishes. Swelling and rupture of cristae and degeneration of microtubules were from these changes. 相似文献
146.
The objective of this study was to analyse the effects of different levels of rumen-degradable protein (RDP) on intake, digestibility
and microbial protein synthesis by supplementing mustard oil cake (MOC) on rice straw-based diet of cattle (Bos indicus) in Bangladesh. A 4 × 4 Latin square design was applied. Four diets having constant energy (7.0 MJ/kg of dry matter (DM))
with varying levels of RDP (M
0 = 4.1 g/MJ (control), M
1 = 6.3 g/MJ, M
2 = 8.3 g/MJ and M
3 = 12.4 g/MJ of metabolizable energy (ME)) were received by each animal for a period of 28 days. A metabolism trial was conducted
for 7 days. Results indicate that with increasing levels of RDP, crude protein (CP) and RDP intake increased significantly
(P < 0.01). The significant (P < 0.01) increase in digestibility values are obtained for DM, organic matter, CP and digestible organic matter in the rumen.
The digestibility of neutral detergent fibre and acid detergent fibre was also increased significantly (P < 0.05). The total nitrogen (N), ammonia-N and total volatile fatty acids increase significantly (P < 0.01) while the rumen pH increased from M
0 to M
2 and decreased thereafter. The efficiency microbial N intake increased significantly (P < 0.01) but showed a curvilinear response with higher RDP level (12.40 g/RDP/MJ ME). This study concludes that supplementation
of RDP from MOC enhances the intake, digestibility and microbial protein synthesis which ultimately increases utilization
of low-quality feed resources that can be used for developing cost-effective feeding systems on a straw-based diet in tropical
regions. 相似文献
147.
Indigenous chicken (IC) and their production systems were characterized to understand how the whole system operates for purposes
of identifying threats and opportunities for holistic improvement. A survey involving 594 households was conducted in six
counties with the highest population of IC in Kenya using structured questionnaires. Data on IC farmers’ management practices
were collected and analysed and inbreeding levels calculated based on the effective population size. Indigenous chicken were
ranked highest as a source of livestock income by households in medium- to high-potential agricultural areas, but trailed
goats in arid and semi-arid areas. The production system practised was mainly low-input and small-scale free range, with mean
flock size of 22.40 chickens per household. The mean effective population size was 16.02, translating to high levels of inbreeding
(3.12%). Provision for food and cash income were the main reasons for raising IC, whilst high mortality due to diseases, poor
nutrition, housing and marketing channels were the major constraints faced by farmers. Management strategies targeting improved
healthcare, nutrition and housing require urgent mitigation measures, whilst rural access road network needs to be developed
for ease of market accessibility. Sustainable genetic improvement programmes that account for farmers’ multiple objectives,
market requirements and the production circumstances should be developed for a full realization of IC productivity. 相似文献
148.
149.
A study was undertaken from October 2006 to March 2007 to determine the prevalence and antimicrobial resistance patterns of Salmonella serovars. Liver, mesenteric lymph nodes, intestinal content, and carcass swab samples (each n?=?186) were collected from 186 apparently healthy slaughtered cattle at Bahir Dar abattoir. Bacteriological analysis was done according to the International Organization for Standardization (ISO 6579 2002). Isolates were serotyped at Agence Française de Securite Sanitaire des Aliments, Cedex, France. Twenty-eight isolates consisting of Salmonella Typhimurium, Salmonella Newport, Salmonella Haifa, Salmonella Heidelberg, Salmonella Infantis, and Salmonella Mishmarhaemek were identified. Salmonella Typhimurium and Salmonella Newport were most frequently isolated while Salmonella Heidelberg and Salmonella Mishmarhaemek were isolated least. Eleven of the 28 (39.3%) were resistant to one or more of the antimicrobials tested. Resistance was shown to ampicillin, chloramphenicol, gentamycin, norfloxacin, polymyxin-B, streptomycin, tetracycline, and trimethoprim. Four of 11 (36.4%) were multiple antimicrobial resistant. All the isolates tested were susceptible to the antimicrobial effects of gentamycin, norfloxacin, and trimethoprim. Eleven, four, and two isolates of the 28 were resistant to streptomycin, tetracycline, and ampicillin, respectively. All isolates of Salmonella Infantis, Salmonella Typhimurium (except one), and Salmonella Mishmarhaemek were susceptible to the tested antimicrobials. One Typhimurium isolate was resistant to chloramphenicol, streptomycin, and tetracycline. Salmonella Haifa was multiply antimicrobial resistant to ampicillin, tetracycline, and streptomycin. All isolates of Salmonella Heidelberg were resistant to streptomycin. Results of this study indicated high level of carcass contamination with antimicrobial-resistant Salmonella serovars which could pose public health risk; suggests need for hygienic slaughtering operations and proper cooking of meat before consumption. Further detailed studies involving different abattoirs, animal products, food items, and animals on different settings were recommended in the study area. 相似文献
150.
Mahr-un-Nisa Shahzad MA Phillips CJ Sarwar M 《Tropical animal health and production》2012,44(5):947-952
Urea is a common ingredient of the diets of intensively fed lambs, but is increasingly required for industrial processes.
Maize steep liquor (MSL) is a by-product of maize grain degradation to produce starch that may be a suitable replacement.
Fifty growing lambs were fed on equinitrogenous diets in which between 0% and 80% of the urea was replaced by MSL; their growth
and metabolism were recorded over 70 days. Increasing replacement of urea by MSL increased feed intake and nutrient digestibilities,
leading to increased growth rates, more efficient feed conversion, and increased nitrogen retention. Concentrations of triiodothyroxin,
thyroxin, glucose, and methionine were increased by replacement of urea by liquor, and plasma urea was reduced. This study
suggests that MSL is a suitable replacement for up to 80% of urea in the diet of rapidly growing lambs. 相似文献