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1.
The presence of antibodies to the intimin β-binding region (Int280-β) of attaching and effacing Escherichia coli (AEEC) in serum from 20 goat kids from 2 herds, as well as in goat colostrum, was investigated by enzyme-linked immunosorbent assay. In addition, the onset and subsequent pattern of shedding of AEEC from the same goat kids over a 6-mo period was investigated. All the colostrum and serum samples tested contained antibodies against Int280-β. The association between the antibody titer and the isolation of AEEC suggests that antibodies to intimin β do not prevent colonization of the intestine by AEEC in goat kids. The AEEC were generally shed only transiently. Most AEEC isolated from the kids belonged to serogroup O26. Three isolates belonged to serogroup O157. These data show that goat kids may be a reservoir of AEEC that are potentially pathogenic for humans.  相似文献   

2.

Background

The study aimed at examining hypoxia-inducible factor (HIF)1α expression in adenocarcinomas and adenomas in bitches in regard to tumour malignancy grade, proliferation, apoptosis and vascularisation. Therefore, paraffin sections of 15 adenomas and 64 adenocarcinomas sampled from 79 dogs aged 6 to 16 years were analysed.

Results

A significantly higher HIF-1α expression was noted in adenocarcinomas in comparison to adenomas (P < 0.0004). Moreover, HIF-1α expression in adenocarcinomas correlated positively with tumour malignancy grade (r = 0.59, P < 0.05), Ki-67 antigen expression (r = 0.43; P < 0.0005), TUNEL-positive cells (r = 0.62, P < 0001) and tumour vascularity measured by quantification of vessels characterized by the expression of von Willebrand Factor (r = 0.57, P < 0.05).

Conclusion

Results of this study indicate a similar biological role of HIF-1α in dogs and in humans, which may confirm suitability of the animal model in investigations on progression of tumours in humans.  相似文献   

3.
Summary

The disposition of sulphadimidine (SDM) and of its N4‐acetyl (N4‐SDM) and two hydroxyl metabolites, 6‐hydroxymethyl‐ (SCH2OH) and 5‐hydroxyasulphadimidine (SOH), was studied in plasma and milk of dairy cows following intramuscular or intravenous administration of sulphadimididine‐33.3% at doses of 10, 45, 50, and 100 mg/kg. The main metabolite in plasma as well as in milk was SCH2OH. The metabolite percentages, the final plasma elimination half‐lives, and the time of peak SDM concentrations in milk are presented for different dosages. The concentrations of SDM and its metabolites in milk ran parallel to those in plasma beyond4 hours p.i. The metabolite concentrations in plasma and milk were lower than those of the parent SDM. Sulphate and glucuronide metabolites could not be detected in milk.

At high doses (45 mg/kg or more) and SDM plasma concentrations exceeding 20 μg/ml, a capacity limited metabolism of SDM to SCH2OH was noticed, viz, asteady state concentration of SCH2OH and a biphasic elimination pattern for SDM and SCH,OH in plasma and milk.

The mean ultrafiltrate ratios of the milk to plasma concentrations with respect to SDM, SCH2OH, SOH, and N4‐SDM were: 0.69, 0.22, 020, and 0.63, respectively.

The total amount of SDM and its metabolites recovered from the milk after milking twice daily over the whole experimental time was less than 2% of the applied dose.

A bioassay method allowed of detecting qualitatively SDM concentrations exceeding 0.2 μg/ml in plasma or milk. Withholding times for edible tissues and milk are suggested.  相似文献   

4.
At present,China's traditional agriculture and animal husbandry has no way to rely on the "fine fodder + straw" feeding model. Only relying on grass and animal husbandry can guarantee China's consumer demand and food safety. However, due to the restraints such as policy, infrastructure, technology, market and organizational factors, the "lacking" status of China's pasture industry is not optimistic. In this paper, we analyze the pasture production, commercial grass production, grass seed production,forage product trade, the import and export volume of different types of pasture products, the current status of pastoral products trading partners and the causes behind it in depth. And concluded that the supply of forage products in China needs to be imported. Imports are growing while exports are generally declining,the pasture trade market is highly concentrated while grassland trading partners are dispersed. Five suggestions are given to provide theoretical guidance for the development of China's pasture industry: increase policy support, promote infrastructure, increase investment in scientific research, strengthen market construction, and develop industrial organizations. © 2019 China Agricultural University. All rights reserved.  相似文献   

5.
6.
A longitudinal study to monitor prevalence and incidence of antibodies against Newcastle disease (ND) virus and prevalence of antibodies against Avian Influenza (AI) virus in scavenging village chickens was conducted in 20 villages within 4 districts of Timor-Lesté. A total of 3600 blood samples was collected from 1674 individual birds in 300 household chicken flocks during three sampling periods (December 2008-February 2009, March-May 2009, and June-August 2009). The mean interval between household visits was 101.6±1.9 days. None of the birds enrolled in the study was vaccinated against ND or AI. A haemagglutination inhibition (HI) test was used to determine antibody titres against ND virus and a competitive ELISA and HI tests were used to detect antibody against AI virus. The bird-level ND seroprevalence pooled across all samplings (adjusted for clustering by households) was 4.4% (95% CI 3.5-5.2). The bird-level ND seroprevalence in each of the three sampling periods (adjusted for clustering by household) was 3.0% (95% CI 2.0-4.0), 6.6% (95% CI 5.1-8.0) and 3.6 (95% CI 2.5-4.6), respectively. A total of 12.6% individual birds tested ND seropositive at least once over the total study period (95% CI 10.5-14.7). The flock-level ND seroprevalence (at least one bird tested had antibodies against ND virus) pooled across all samplings was 15.9% (95% CI 13.5-18.3). A total of 35.3% flocks had a minimum of one bird being ND seropositive at least once over the study period. The bird-level incidence rate for the period between the first and the second sampling and between the second and the third sampling was 5.6 (95% CI 4.1-7.5) and 0.5 (95% CI 0.5-3.8) per 10,000 bird-years-at-risk, respectively. A total of 1134 serum samples from the last sampling period between June and August 2009 was tested for antibodies against AI virus. Only 4 samples tested Influenza A positive, indicating a bird-level seroprevalence level for Influenza A of 0.4% (CI 0.0-0.7%). These Influenza A positive samples were further tested for HI antibodies against AI virus subtypes of H5N1, H5N3, H7N3 and H9N2, but all tested negative, suggesting that the influenza antibodies in those four birds resulted from exposure to low pathogenic AI viruses of different H subtypes. Our results indicate that village chickens in Timor-Lesté are exposed to ND virus; there was a higher risk of infection during the early months of 2009 than either immediately prior or subsequent to this. No evidence of infection of village chickens with H5, H7 or H9 AI viruses was detected in this study.  相似文献   

7.
The objective of this study was to explore the expression differences of integrin αv in different parts of the fallopian tube at different reproduction stages of yak, and provide some important theoretical foundations for understanding the effect of integrin αv on the reproductive performance of yak. The samples of the tubal umbrella, ampulla, and isthmus of healthy female yaks (3-6 years old) during follicular, luteal and pregnancy stages were collected, the fallopian tubes of the follicular phase, the luteal phase and the pregnancy phase were divided into 9 groups according to the umbrella, ampulla and isthmus. Real-time PCR (qRT-PCR) and Western-blotting (WB) were used to detect the expression of integrin αv gene and protein. The expression of integrin αv protein was localized by immunohistochemistry. Results: 1) qRT-PCR results showed that, during the follicular phase, the expression of the integrin αv gene in the umbrella of the fallopian tube was the highest and extremely significantly higher than those in the ampulla and isthmus (P<0.01). During the luteal phase, the expression of the integrin αv gene in the isthmus of the fallopian tube was the highest and extremely significantly higher than those in the umbrella and ampulla (P<0.01). During the pregnancy phase, the expression of the integrin αv gene in the umbrella of the fallopian tube was the highest and extremely significantly higher than those in the ampulla and isthmus (P<0.01). 2) Western-blotting results showed that, during the follicular phase, the expression of integrin αv protein in the umbrella of the fallopian tube was the highest and extremely significantly higher than those in the ampulla and isthmus (P<0.01). During the luteal phase, the expression of integrin αv protein in the isthmus of the fallopian tube was the highest and extremely significantly higher than those in the umbrella and ampulla (P<0.01). During the pregnancy phase, the expression of integrin αv protein in tubal isthmus and umbrella was not significantly different, but these were extremely significantly higher than that in the ampulla (P<0.01). 3) The results of immunohistochemistry showed that integrin αv protein was positively expressed in ciliated cells, secretory cells, basal cells, muscular layers and serous glands of the fallopian tube umbrella, ampulla and isthmus. The results indicated that the expression of integrin αv in different parts of the fallopian tube at different reproduction stages of the yak were significantly different, which showed that αv might be involved in a series of reproductive processes such as fertilization and early embryonic development, the results provided basic information for the study of yak's reproductive performance.  相似文献   

8.
1. The role of certain fish meals in the production of localised gizzard erosion is confirmed.

2. Lesions typical of gizzard erosion could be produced by the addition of histamine to the diet.

3. The amount of histamine occurring naturally in fish meal depends on the species of fish and the extent and nature of bacterial spoilage.

4. These variables may explain why histamine has not been implicated previously and also why there have not been consistent associations between the condition and geographical source or common factors in bulk consignments of the meal.  相似文献   


9.
In this study, effects of oral β-carotene supplementation to mares (β-carotene group: 1000 mg/day, n = 15; control group: n = 15) from 2 weeks before foaling until 6 weeks thereafter on concentrations of β-carotene, vitamin A and α-tocopherol in plasma, colostrum and milk and plasma of their foals were determined. In addition, effects on fertility were studied. Beta-carotene concentrations increased in plasma and colostrum of β-carotene-supplemented mares compared to control mares (p < 0.05). In mares of both groups, β-carotene concentrations were higher in colostrum than in milk (p < 0.05). In foals, β-carotene concentrations increased with colostrum uptake and were higher in foals born to supplemented mares (p < 0.05; control group: 0.0003 ± 0.0002 μg/ml on day 0, 0.008 ± 0.0023 μg/ml on day 1; β-carotene group: 0.0005 ± 0.0003 μg/ml on day 0, 0.048 ± 0.018 μg/ml on day 1). Concentrations of vitamin A and α-tocopherol were higher in colostrum than in milk (p < 0.05) but did not differ between groups. Concentration of α-tocopherol in plasma of mares decreased over time and in foals, increased markedly within 4 days after birth. All but one mare (control group) showed oestrus within 2 weeks post-partum. Occurrence of oestrus did not differ between groups. More mares of the control group (7/7 vs. 5/12 in the β-carotene group) became pregnant after being bred in first post-partum oestrus (p < 0.05). In conclusion, β-carotene supplementation to mares increased β-carotene concentrations in plasma, colostrum and milk of mares and plasma of their foals but had no positive effects on fertility.  相似文献   

10.
1. The objective of the present study was to examine the effect of in ovo injection of disaccharides (DS), disaccharides and glutamine (DS + Gln) or disaccharides and β-hydroxy-β-methylbutyrate (DS + HMB) at d 23 of incubation on the development of the small intestine. 2. In DS + Gln-injected ducks, the greatest relative small intestine mass and muscularis layer thickness among 4 treatments was observed from d 25 of incubation to 7 d of age. 3. Jejunal sucrase activity in DS-injected ducks was significantly greater than in controls at hatch and on d 7. 4. In DS + HMB-treated ducks, a tendency toward slightly higher jejunal DNA concentration was observed throughout the experiment. 5. Greater body weight was found in DS + Gln and DS + HMB treated ducks in the first two weeks. However, there was no significant difference in the market weight (35 d) of ducks among the 4 treatments. 6. The results of present study suggest that administering disaccharides and Gln, or disaccharides and HMB, to the duck embryos exerted a beneficial effect on the early development of small intestine and on growth performance.  相似文献   

11.
1. The effects of lycopene-enriched extenders on the in vitro quality of turkey semen including lipid peroxidation were examined after chilled and frozen storage.

2. Five pools of semen diluted in extenders containing 0, 0·05 or 0·1?mg/ml of lycopene were stored at 5°C for 48?h or cryopreserved as pellets and the following variables determined in fresh samples and samples stored chilled or frozen: sperm motility, viability, osmotic resistance, DNA integrity and lipid peroxidation (as malonaldehyde production).

3. Semen quality was generally compromised after storage, especially post-freezing. However, in the presence of the highest dose of lycopene, both the viability and osmotic-resistance of chilled spermatozoa and the DNA integrity of frozen spermatozoa were similar to those of fresh spermatozoa.

4. Greater lipid peroxidation was detected in refrigerated compared to fresh or cryopreserved spermatozoa. However, spermatozoa chilled in lycopene-enriched extenders showed significantly lower malonaldehyde levels than those chilled without lycopene, while the addition of lycopene to the freezing medium served to maintain the lipid peroxidation levels observed in fresh semen.

5. In conclusion, the presence of lycopene in the extender improved the survival of turkey spermatozoa after liquid-storage and protected DNA integrity against cryodamage. The beneficial effects of lycopene observed could be related to its capacity to diminish sperm lipid peroxidation during refrigeration or cryopreservation.  相似文献   

12.
13.
This study deals with disorders of sexual development in humans, wildlife and animals in an urban nature reserve (RNR) and a currently DDT-sprayed malarial area. High levels of oestrogenic chemical residues in water, sediment and tissue; skewed sex ratios; reduced biodiversity; gonadal malformations in sharptooth catfish and freshwater snails; intersex in catfish; and impaired spermatogenesis in catfish and striped mouse are of serious concern in the RNR. Persistent eggshell thinning in African darter eggs, intersex in male Mozambican tilapia, follicular atresia in females and impaired spermatogenesis in males following laboratory exposure of parent fish to environmentally relevant DDT and DDE concentrations, and abnormalities in freshwater snails were found in the DDT-sprayed area. Human studies related to DDT exposure indicated impaired semen quality, a weak association with sperm chromatin defects and higher risks for external urogenital birth defects in those who were born to mothers whose houses were sprayed and those who were homemakers (stay at home mother) instead of being employed. These findings indicate that diseases of sexual development occurred in both human and wildlife populations exposed to environmental endocrine disruptor chemicals in South Africa. The chemical mixtures, possibly related to disorders of sexual differentiation (DSD), were very different between the two. However, DSD occurred concurrently in the malarial area, possibly indicating that humans and wildlife shared exposures. Moreover, it emphasizes the importance of suspecting disease in the other when disease is found in either human or wildlife populations.  相似文献   

14.
A slaughterhouse survey to determine prevalence and larval burden of Oestrus ovis larvae in sheep and goats was performed monthly during one year in Pézenas, South of France, northern mediterranean region. A total of 1303 sheep and goat heads were selected at random. O. ovis larvae were found in 274 sheep out of 631 (43.4%), and the prevalence rate varied from 14.3% in February to 65% in October. The mean number of larvae in infected sheep heads was 10.86 with 9.24 L1, 0.91 L2 and 0.71 L3. One hundred and ninety-one goats out of 672 were infected (28.4%), and the prevalence rate varied from 6.25% in September to 47.1% in April. In infected goat heads, the mean parasitic burden was 5.35 with 4.04 L1, 0.73 L2 and 0.58 L3. These results confirm worldwide observations indicating that the prevalence and the parasitic burdens are less in goats than in sheep.  相似文献   

15.
There is a variety of professions working with village chickens in developing countries, including farmers, veterinarians and chicken traders. People from all these occupations were involved in a participatory rural appraisal to investigate husbandry practices and trade of village chickens in Myanmar. Data were collected in two climatically different regions of the country, in the Yangon and in the Mandalay divisions. The breeding and training of fighting cocks was practised only in the Mandalay division, with well-trained birds sold for very high prices. Apart from this, chickens were raised in both regions mainly for small disposable income and were generally sold when money was needed, in particular during religious festivals. Chicken traders on bicycles, often called ‘middle men’, usually purchase birds from farmers in about 10 villages per day. Several ‘middle men’ supply birds to wealthier chicken merchants, who sell these birds at larger chicken markets. There is in general limited knowledge among farmers about the prevention of Newcastle disease via vaccination. Commercial indigenous chicken production is practised in Myanmar, but family poultry farming dominates indigenous chicken production in the country.  相似文献   

16.
This study was conducted to determine the impact of antioxidant (α-tocopherol) supplementation in the cryopreservation extender and three different freezing rates (FRs) on quality of post-thaw semen to elaborate a new protocol for stallion semen cryopreservation. Six ejaculates from each of four stallions were subjected to cryopreservation with a commercial extender (Gent, Minitub Iberia, Spain), without any supplementation (control) or supplemented with 2 mM α-tocopherol. The semen was exposed to three different freezing rates between 5°C and −15°C: slow (5°C/min), moderate (10°C/min), and fast (20°C/min). After thawing, the sperm viability (Sybr-14 and propidium iodide [PI]), mitochondrial membrane potential (MMP) (5,5′,6,6′-tetrachloro-1,1′,3,3′tetraethylbenzimidazolyl carbocyanine iodine), lipid membrane peroxidation (LPO; C11-BODIPY581/591), and apoptosis status (fluorescein isothiocyanate–conjugated annexin V and PI) of the plasmatic membrane of each sample were determined by flow cytometry. For both extenders, the percentage of viable cells was higher for spermatozoa cooled at 5°C/min than at 10°C/min and 20°C/min (P ≤ .05). The FR of 20°C/min demonstrated a lower value of MMP than the FR of 5°C/min and 10°C/min (P ≤ .05). The α-tocopherol extender improved (P ≤ .05) post-thaw membrane LPO; however, it did not improved viability and the apoptosis status of the sperm plasmatic membrane after thawing. In conclusion, results clearly indicate that the cryosurvival of stallion spermatozoa is improved when FR of 5°C/min is used from 5°C to −15°C.  相似文献   

17.
The present study aimed at examining the possible role of tannins and flavonoids on the in vitro anthelmintic properties of the extracts of two plants from the southern area of Western Africa, i.e. Newbouldia laevis and Zanthoxylum zanthoxylo?des. Extracts of the two plants were prepared by use of acetone/water (70/30) and their anthelmintic activity was measured by use of the larval exsheathment inhibition assay (LEIA) applied on the abomasal species, Haemonchus contortus and the intestinal species Trichostrongylus colubriformis. Three concentrations of extracts were evaluated to examine the possible dose effect. In addition, the possible involvement of tannins and flavonoids was examined by comparing the levels of inhibition of larval exsheathment obtained with the same extracts, after of not addition of PVPP which forms complexes with these compounds. The results indicate significant effects with both plants and both nematode species. In the range of concentrations examined, the results were dose-dependent for N. laevis extracts but not for Z. zanthoxylo?des because the three doses applied provoked a similar highly significant inhibition whatever the tested dose. The use of PVPP indicated for both plant and nematode species, that tannins and flavonoids are involved partly in the effect but that some other biochemical compounds were also involved in both plants.  相似文献   

18.

Background

Syringomyelia (SM) is common in the Cavalier King Charles Spaniel (CKCS). Dogs with syringes express clinical signs or might be clinically silent.

Objectives

To investigate the prevalence and heritability of symptomatic SM, the association between clinical signs and magnetic resonance imaging (MRI) findings, and long‐term outcome.

Animals

All CKCS registered in the Danish Kennel Club in 2001 (n = 240).

Methods

A cross‐sectional questionnaire‐based prevalence study validated by telephone interviews and clinically investigated clinical signs of SM. Dogs were 6 years at the time of investigation. A prospective observational litter study including clinical investigations, MRI and 5‐year follow‐up of symptomatic and asymptomatic siblings. Heritability was estimated based on the scale of liability in the study population and litter cohort.

Results

The cross‐sectional study estimated a prevalence of symptomatic SM at 15.4% in the population. Thirteen symptomatic and 9 asymptomatic siblings participated in the litter study. Spinal cord syringes were confirmed in 21 of 22 littermates (95%). Syrinx diameter and mean syrinx : spinal cord ratio were significantly correlated with clinical signs (P < .01). Estimated heritability of symptomatic SM was 0.81. Symptomatic SM motivated euthanasia in 20%. Dogs with syringes, which expressed no clinical signs at the age of 6, remained asymptomatic in 14/15 cases (93%).

Conclusions and Clinical Importance

The prevalence of symptomatic SM is high and genetics have a high impact on clinical disease expression. Further investigations of factors influencing the outbreak threshold of clinical signs of SM are desirable.  相似文献   

19.
Tropical Animal Health and Production - A total of 636 fecal samples collected from piglets with and without diarrhea during 2009 to 2013 were tested for porcine kobuvirus by RT-PCR. From a total...  相似文献   

20.
This review of tick paralysis caused by Ixodes holocyclus in Australia addresses the question: What are the key discoveries that have enabled effective treatment and prevention of tick paralysis in dogs and cats? Critical examination of 100 years of literature reveals that arguably only three achievements have advanced treatment and prevention of tick paralysis in animals. First, the most significant treatment advance was the commercial availability of tick antiserum in the 1930s. Hyperimmune serum currently remains the only specific anti-paralysis tick therapy available to veterinarians in Australia. Second, advances in veterinary critical care have increased survival rates of the most severely affected dogs and cats. Critical care advancements have been enabled through specialised veterinary hospitals that can provide appropriate care 24 h a day, and advanced training of veterinarians, veterinary nurses and technicians. Third, perhaps that biggest advance of all in the last 100 years of research has been the commercial availability of the isooxazoline class of acaricidal preventatives in Australia specifically for I. holocyclus. This highly effective class of preventatives offers long duration of action, low cost, spot-on or oral formulations and a low rate of adverse reactions. Animal owners and veterinarians now have the most useful tool of all – a reliable preventative. This review reveals the key events in research over the last 100 years and the tortuous pathway to delivering better treatment and preventative options for this enigmatic Australian parasite.  相似文献   

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