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101.

Background

The primary aims of this study were to determine the incidence of Giardia infections in dairy herds on farms in the New York City Watershed region and to evaluate risk factors associated with infections. Because co-infections of Giardia and Cryptosporidium spp. are common in this population, we also evaluated the effect of herd infection status on Giardia infections.

Methods

Farms were grouped into three cohorts based on their prior infection status with Giardia and/or Cryptosporidium spp. The sampling plan included collecting fecal samples from all calves below 30 days of age and proportional sampling of calves, young stock, and adults. A total of 10,672 fecal samples were collected and analyzed for the presence of Giardia cysts using zinc sulfate flotation. Herds enrolled in the study were sampled seasonally for a study period of two years. The probability of shedding cysts past a certain age and the factors that influenced the likelihood of shedding were evaluated using survival analysis. Linear regression was used to evaluate factors that were associated with the intensity of shedding.

Results

The majority of Giardia infections occurred in calves within their first 180 days of age, with the most number of calves shedding Giardia cysts between 11 and 20 days of age. The incidence of shedding of Giardia cysts ranged from 0.0004 per animal day for cattle in the low risk cohort to 0.0011 per animal day for cattle in the high risk cohort. The likelihood of shedding was influenced by the prior infection status of the herd and the season of collection. Infected animals shed on average 9,658 cysts/gram and the intensity of shedding Giardia cysts varied significantly with the age (p < 0.0001) and the season of collection (p = 0.0151 for Spring).

Conclusion

Giardia infections are common in dairy herds in the New York City watershed, particularly in calves less than 6 months of age. Seasonality may be an important factor in the perpetuation of infections based on changes in management practices corresponding to weather patterns of a particular season. A dairy herd''s prior infection status with Cryptosporidium influences the likelihood of infection with Giardia.  相似文献   
102.
This work discusses some of the important considerations of wild ostrich evolution, behaviour and ecology, as items included in ostrich production. In the process considerable research was conducted by collating information from peer-reviewed papers; textbooks; manuals; and PubMed and Agricola searches. Selected areas reviewed included activity of ostriches; feeding and water needs; sexual maturity; egg laying and natural incubation; selected physiological parameters; and predation. There is an immediate and urgent need to conserve and protect the rapidly declining populations of wild ostriches with the committed involvement of governments and funding bodies.  相似文献   
103.
A retrospective study of 43 cases of temporohyoid osteoarthropathy was performed to evaluate the epidemiological features and a possible association with crib‐biting. Data collected from records included case details, what diagnostics were utilised, whether medical or surgical treatment was administered, and outcome. Owners were contacted via telephone and asked whether the horse had displayed crib‐biting behaviour. Forty‐three horses were diagnosed with neurological disease associated with temporohyoid osteoarthropathy, 62.8% of which were Quarter Horse‐types. Median age at presentation was 10 years and median duration of neurological signs prior to presentation was 3 days. Skull radiographs and guttural pouch endoscopy were used to definitively diagnose temporohyoid osteoarthropathy in 72% of the cases. Of 43 horses, 21 received medical treatment and 15 surgical treatment, with an overall survival rate of 55.8%. Crib‐biting was observed in 31.3% of cases and there was a significant association between being afflicted with THO and likelihood of possessing the behaviour. Horses with neurological disease associated with THO were 8 times more likely to be crib‐biters compared to the general population.  相似文献   
104.
The present study reports on phytoplasma induced fasciation in Crassula argintea (Crassulaceae). DNA was extracted from symptomless and fasciated tissues and amplified by nested PCR using universal primers P1/P7 followed by R16F2n/R16R2 produced amplicons of 1.2 Kb. The nucleotide sequence analyses of the amplicons indicated that fasciated plants were infected by phytoplasma. Phylogenetic analysis placed the Crassula fasciation phytoplasmas in 16SrII-D group. Histochemical staining for reactive oxygen species indicated that phytoplasma infected (PI) tissues possess significantly higher levels of hydrogen peroxide (H2O2) rather than superoxide (O2 ·-) as compared with symptomless tissues. PI tissues were also associated with a significant increase in antioxidant enzyme activities (catalase, peroxidase, polyphenol oxidase, and glutathione reductase) and electrolyte leakage as compared with symptomless tissues.  相似文献   
105.
In vivo and in vitro protein digestibility of 0% to 60% soybean meal protein (SBM) substitution from fishmeal protein was conducted for bagrid catfish Mystus nemurus juveniles. Seven experimental diets containing 35% protein and 15% lipid were fed to bagrid catfish to determine the in vivo protein digestibility. In vitro methods were determined using pH stat, pH shift, spectrophotometric assay and sodium dodecyle sulphate polyacrylamide gel electrophoresis (SDS‐PAGE) with different enzyme mixtures (crude intestinal extract of bagrid catfish, Lazo 1‐enzyme, Hsu 3‐enzyme, Saterlee 4‐enzyme). In vivo and in vitro protein digestibility decreased with increased SBM protein substitution with highest tolerance level of 10% (in vivo). pH stat and pH drop methods showed the highest degree of hydrolysis (DH) and relative protein digestibility (RPD) using Saterlee 4‐enzyme system. However, pH stat method showed highest correlations (r2 = 0.9263) with the in vivo results using crude intestinal enzyme extract compared to other enzyme systems. The highest correlation of the in vitro methods using crude intestinal enzyme extracts of bagrid catfish was determined using spectrophotometric assay (r2 = 0.9284) followed by pH stat (r2 = 0.9263), SDS‐PAGE (r2 = 0.8348) and pH drop (r2 = 0.6777). All the in vitro methods tested are suitable to rapidly determine protein digestibility for bagrid catfish except for pH drop.  相似文献   
106.
A field experiment was conducted using Ceranock bait station, "attract and kill" system to combat Mediterranean fruit fly, Ceratitis capitata, in apricot orchards, Central of lraq during the 2013 field season. Control program was implemented in three orchards of mixed apricot varieties. Ceranock traps were hung in each tree of two separate orchards. Delta and McPhail traps were used to monitor Medfly population density in each treated and control orchards. Results indicated that Medfly activity in apricot orchards started during the last week of April coincided with the beginning of maturity for fruits of early varieties. The total of trapped insects in monitoring traps after one week of Ceranock application were 0, 1 and 31 adults for the 1st, 2nd and the control orchards, respectively. Three weeks later and on, the number of trapped adults started to increase dramatically. At the end of apricot season and after 45 days of Ceranock trap application, the number of trapped insects in monitoring traps reached 110, 111 and 2,349 adults/week, respectively, for the 1st, 2nd and 3rd orchard. The use of Ceranock traps reduced Medfly population density by 86%-97%. The percentage of fruit injuries in early maturing varieties were 0.75%, 1% and 34% for the 1st, 2nd and control orchards, respectively. While, late varieties were 2% and 3% for 1st and 2nd orchards, and 69% for the control. The percentage of reduction in fruit damages reached to 95% and 97%, respectively in the 1st and 2nd orchard. The results of this study demonstrate clearly the efficacy of Ceranock bait station, "attract and kill" system as a control measure for Medfly in apricot orchards.  相似文献   
107.
A total of 17 microsatellite deoxyribonucleic acid loci used routinely for horse parentage control were used to evaluate genetic diversity among normal Arabian horses and severe combined immunodeficiency (SCID) carrier Arabian horses (ArS) and normal Arab-Barb horses and SCID carrier Arab-Barb horses (ArbeS). On the basis of the genotype of 186 horses, mean allelic diversity was estimated as 6.82, 5.53, and 6.7059 in normal Arabian horses, ArS, and for both groups of Arab-Barb horses, respectively. Five specific alleles were observed in ArS and ArbeS, with one common with ArS at HMS6, whereas five alleles common between ArS and ArbeS had a high frequency. Expected and observed heterozygosity showed great heterogeneity in the population studied and were similar or higher when compared with other studies on Arabian horses. Coefficient of gene differentiation Gst of Nei associated with Nei’s genetic distance and multivariate correspondence analysis indicated a possible differentiation between the studied populations when analyzed separately according to breed. Probability of assignment of a horse to a specific group was assessed using a full and partial Bayesian approach. In all, 80.6% of Arab horses and 78.2% of Arab-Barb horses were assigned properly with a partial Bayesian test, which provided better results than the full one. These findings will be useful for identification of SCID carrier horses by using the microsatellite deoxyribonucleic acid loci used routinely for horse parentage control in our laboratory.  相似文献   
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110.
Tropical Animal Health and Production - The main objective of this research was to evaluate the effects of chemical treatment and sonication (ultrasound) processing on the fiber composition and...  相似文献   
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