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Evaluation of 99mTc-diethylenetriaminepentaacetic acid nuclear imaging for quantitative determination of the glomerular filtration rate of dogs.
1986
Krawiec D.R. | Badertscher R.R. II | Twardock A.R. | Rubin S.I. | Gelberg H.B.
Effect of early lactation milk yield on reproductive disorders in dairy cows.
1994
Grohn Y.T. | Hertl J.A. | Harman J.L.
Association between individual cumulative milk yield and various reproductive disorders in 56,772 Finnish Ayrshire cows belonging to 5,912 herds in 80 communities was studied. All cows delivered calves between September 1985 and September 1986. Five logistic regression models were fitted, 1 for each outcome disorder of interest: early metritis, late metritis, silent heat, ovarian cyst, and other infertility. Cumulative individual 37-day milk yield was used in the early metritis model, and cumulative individual 60-day milk yield was used in the other models, on the basis of median days in milk when these disorders developed. Cumulative 305-day herd milk yield, parity, calving season, presence or absence of other disorders, and community were also included in the models. Point estimates from the models represented odds ratios for the likelihood of having the outcome disorder.Lactational incidence risks for the 5 reproductive disorders studied were: early metritis (2.4%), late metritis (1.1%), silent heat (5.4%), ovarian cyst (6.6%), and other infertility (2.1%). The risk of early metritis decreased with increasing 37-day milk yield. The risk of silent heat, ovarian cyst, and other infertility increased with increasing 60-day milk yield; 60-day milk yield had no effect on late metritis. The 305-day herd milk yield increased the risk of early metritis, ovarian cyst, and other infertility; it had no effect on late metritis or silent heat. Parity had an effect on all disorders, except late metritis. Cows that delivered calves during the colder, darker seasons of the year had a higher risk of reproductive disorders than did those that delivered calves at other times of the year. A number of other disorders, reproductive and otherwise, were significant predictors of development of the outcome disorders.
显示更多 [+] 显示较少 [-]Effects of bolus injection of epinephrine and norepinephrine on systolic time intervals in stress-resistant and stress-susceptible pigs.
1986
Malo D. | DeRoth L.
Numbers of Sertoli cells, quantitative rates of sperm production, and the efficiency of spermatogenesis in relation to the daily sperm output and seminal quality of young beef bulls.
1989
Berndtson W.E. | Igboeli G.
Data from 34 yearling Hereford or Angus bulls were used to investigate relationships of testicular size, quantitative rates of sperm production, Sertoli cell numbers, numbers of germ cells supported per Sertoli cell, and the efficiency of spermatogenesis to daily sperm output and seminal quality. Two ejaculates were collected by electroejaculation from each bull on each of 2 days/week throughout the study. The percentage of progressively motile sperm and the percentage of morphologically normal sperm were determined from aliquots of fresh semen. Additional aliquots of semen were frozen in glass ampules or plastic straws and subsequently evaluated for postthaw motility and percentage of sperm with intact acrosomes. Sertoli cell numbers, the numbers of germcells per Sertoli cell, and the efficiency of spermatogenesis were unrelated to the quality of fresh or frozen semen (P greater than 0.05). In first ejaculates, the numbers of sperm and motile sperm were related (P less than 0.05) to testicular parenchymal weight (r = 0.38, and 0.50), daily sperm production (r = 0.45 and 0.53), and spermatids per gram of testicular parenchyma (r = 0.35 and 0.34). Testicular parenchymal weight and daily sperm production also were related to daily sperm output and to the average daily motile sperm output of these bulls (P less than 0.05), but could account for less than 25% of the variability in these end points among bulls.
显示更多 [+] 显示较少 [-]Relative anticipated erythrocyte sedimentation rate of cattle blood, as measured by 45 degree-angled Wintrobe hematocrit tube, for ambient temperature and PCV value.
1988
Lee B.H. | Park Y.W. | Shin J.W.
Each of twenty blood samples taken from apparently healthy Korean cows was used to produce five different mixtures of autologous plasma and blood corpuscles such that their values of packed cell volume(PCV) lay between 10 to 50ml/100ml. The measurement of erythrocyte sedimentation rate(ESR) using 45 degree-angled Wintrobe hematocrit tube, 3mm bore, (45deg C-Wintrobe-ESR) was practised for the blood of various levels of PCV lowered. Correlation of the ESR to PCV showed curvilinear regression each in three levels of PCV under the ambient temperature of 10deg C, 20deg C and 30deg C. Correlation of the ESR to the ambient temperature showed linear regression each in five levels of PCV. The ESR increased with ascending ambient temperature, and magnitude of the increase of the ESR became greater as the level of PCV lowered. Correlation of the ESR to PCV showed curvilinear regression each in three levels of the ambient temperature, and the ESR was increased with decreasing PCV. The data were statistically analysed and a list of relative anticipated 45deg C-Wintrobe-ESR values for PCV and ambient temperature was presented.
显示更多 [+] 显示较少 [-]Effective control of Johne’s disease in large Czech dairy herds
2022
Fichtelová, Věra | Králová, Alena | Babak, Vladimir | Kovařčík, Kamil
Johne’s disease, caused by infection with Mycobacterium avium subsp. paratuberculosis (MAP), causes economic losses in dairy herds due to reduced milk production and premature culling. A test-and-cull strategy coupled with changes in calf rearing management preventing new infections has been introduced into infected herds to control MAP prevalence. This study appraised the effectiveness of these practice changes. In 19 large dairy herds (of a median 470 milk-producing cows), implementing MAP control measures for 3–7 years, a serum ELISA was used to detect infected cows in their dry-off period. The number of ELISA-positive animals per year (EPAY) was calculated and statistical analysis was used to test whether the EPAY total decreased during the control period and to analyse the EPAY in relationship to the duration of the control programme. Statistical support was found for a decrease of EPAY over time (P < 0.01, odds ratio 0.756) and in 14 herds a significant fall in the percentages of EPAY during the test period (P ≤ 0.05) was noted. Our results demonstrated the effectiveness of the control measures in place to reduce MAP infection in herds with initial EPAY ≥3.36%. The missing decreasing trend in the remaining five herds with low average initial EPAY suggested the need for additional measures to reduce the number of infected animals in these herds.
显示更多 [+] 显示较少 [-]Relationship between the content of chlorinated hydrocarbons and fatty acid composition of milk fat
2018
Pietrzak-Fiećko, Renata
Reports that the presence of persistent organic pollutants in fat may affect fatty acid metabolism prompted this research aiming to study the relationship between the contents of γ-HCH and DDT, DDE, DDD, and ΣDDT, and fatty acid composition of milk fat. The material consisted of 50 samples of cow and mare milk, collected in 2015. Ludwicki’s and the Röse-Gottlieb and IDF Standard methods were used to prepare the samples. Statistical analyses were conducted using Statistica 12.0. There was a negative correlation between the content of γ-HCH and C16:1, C17:1, C18:1c9, C18:1c9c12, and ΣMUFA in cow milk fat and C13:0, C14:0, and C10:1 in mare milk fat. A positive correlation was observed between γ-HCH and C6:0 to C12:0, C14:0, C18:1t16, and ΣSFA in cow milk fat, and between this compound and C14:0iso, C16:1, C17:1, C18:1c9,11, and ΣMUFA in mare milk fat. A negative correlation between the contents of ΣDDT and C16:1, C17:1, C18:1c9,11,13 and ΣMUFA in cow milk fat and C16:0iso, C17:0, and C18:3 in mare milk fat was noted. A positive correlation was found between the contents of ΣDDT and saturated and polyunsaturated fatty acids and ΣSFA and ΣPUFA in cow milk fat, and C18:2c9c12 in mare milk fat. The correlation between the content of selected organochlorine compounds and the composition of fatty acids in cow and mare milk fat indicates the strong influence of these environmental pollutants on the nutritional value of milk fat.
显示更多 [+] 显示较少 [-]Staphylococcus spp. from wild mammals in Aragón (Spain): antibiotic resistance status
2020
García, Leticia Alcalá | Torres, Carmen | López, Antonio Rezusta | Rodríguez, Carmelo Ortega | Espinosa, Jesús Orós | Valencia, Carmen Simón
Antimicrobial resistance is a global health threat. It has been studied in humans and domestic animals, but there is a lack of data on wild animals. The objective of this study is the elucidation of its patterns in Staphylococcus spp. isolated from wild mammals of the Autonomous Community of Aragón (Spain). A total of 103 mammals (Artiodactyla, Carnivora, Chiroptera, Erinaceomorpha, and Lagomorpha) were studied. A recovery centre provided 32 and hunting 71. Nasal and faecal samples yielded 111 staphylococci, which were identified by matrix-assisted laser desorption/ionization–time of flight mass spectrometry. A susceptibility test to 11 antibiotics was carried out, and statistical analysis was performed. Some differences were detected in bacterial prevalence depending on how the mammal fed. Artiodactyla, mainly hunted, were predisposed to carry coagulase-positive staphylococci. The staphylococci species recovered were resistant to at least two classes of antibiotics, and were disseminated in all of the geographical areas studied. Resistant staphylococci are widely distributed in the wild mammals in the areas of the study, but the resistance quantified in them is lower than that to be expected if the use of antibiotics in farms had a direct influence on the wildlife and its environment. On the other hand, resistance to antibiotics restricted to human use was widely disseminated in various wild animal species.
显示更多 [+] 显示较少 [-]Comparison of microscopy, card agglutination test for Trypanosoma evansi, and real-time PCR in the diagnosis of trypanosomosis in dromedary camels of the Abu Dhabi Emirate, UAE
2022
Habeeba, Shameem | Khan, Rashid Ali | Zackaria, Hassan | Yammahi, Saeed | Mohamed, Zulaikha | Sobhi, Wissam | AbdelKader, Ayman | Alhosani, Mohamed Ali | Muhairi, Salama Al
Trypanosomosis is an important disease of dromedary camels caused by the pathogenic protozoan Trypanosoma evansi. This study aimed to compare three different tests for its diagnosis in this species: conventional microscopy, the card agglutination test for trypanosomosis/T. evansi (CATT/T. evansi) and real-time PCR. Whole blood and serum samples collected from 77 dromedary camels of Abu Dhabi, United Arab Emirates, were analysed with the test methods stated. Statistical analysis was done using McNemar’s chi-squared test, and Cohen’s kappa index (κ) was calculated. We obtained results with positivity of 18% (14/77) by microscopy, 22% by CATT (17/77) and 60% (46/77) by real-time PCR, with the chain reaction detecting at a respectively three- and two-fold greater rate than the other techniques. Analysis of the data revealed a relative sensitivity of 30.4% and 37.0% for microscopy and CATT, respectively, compared to real-time PCR. The difference between the real-time PCR’s sensitivity and those of the other methods was statistically significant, with X² values of 30.03 and 20.1, respectively (df = 1 and P = 0.05 in both cases). Agreement of microscopy results with those of with CATT was good (κ = 0.72; 95% CI = 0.62–0.82). Cohen’s kappa index showed fair agreement of real-time PCR with microscopy (κ = 0.26; 95% CI = 0.16–0.36) whereas it was in poor agreement with CATT (κ = 0.09; 95% CI = 0.02–0.15). Real-time PCR was found to be more sensitive than microscopy and CATT.
显示更多 [+] 显示较少 [-]Detection of myxoma virus in the classical form of myxomatosis using an AGID assay: statistical assessment of the assay’s diagnostic performance
2020
Kwit, Ewa | Osiński, Zbigniew | Lavazza, Antonio | Rzeżutka, Artur
The aim of the study was to estimate the diagnostic sensitivity (DSe) and specificity (DSp) of an agar gel immunodiffusion (AGID) assay for detection of myxoma virus (MYXV) in the classical form of myxomatosis and to compare its diagnostic performance to that of molecular methods (IAC-PCR, OIE PCR, and OIE real-time PCR). A panel of MYXV-positive samples of tissue homogenates with low (1 PCR unit – PCRU) and high (3,125 PCRU) virus levels and outbreak samples were used for method comparison studies. The validation parameters of the AGID assay were assessed using statistical methods. The AGID attained DSe of 0.65 (CI₉₅%: 0.53–0.76), DSp of 1.00 (CI₉₅%: 0.40–1.00), and accuracy of 0.67 (CI₉₅%: 0.55–0.76). The assay confirmed its diagnostic usefulness primarily for testing samples containing ≥3,125 PCRU of MYXV DNA. However, in the assaying of samples containing <3,125 PCRU of the virus there was a higher probability of getting false negative results, and only molecular methods showed a 100% sensitivity for samples with low (1 PCRU) virus concentration. The overall concordance of the results between AGID and IAC-PCR was fair (ĸ = 0.40). Full concordance of the results was observed for OIE PCR and OIE real-time PCR when control reference material was analysed. Findings from this study suggest that AGID can be used with some limitations as a screening tool for detection of MYXV infections.
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