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501.
Three years of hourly sequential precipitation samples from central Long Island, New York were analyzed to determine the relationships between acidity and conductivity and concentrations of sulfate, nitrate plus nitrite, nitrogen in ammonium, sodium, and chloride ions. Relationships between precipitation acidity and meteorological conditions were also studied. Hydrogen ion concentrations are similar to those elsewhere in the northeastern United States. They are best correlated with sulfate concentrations but also correlate with concentrations of nitrogen in nitrate plus nitrite and nitrogen in ammonium ion. Concentrations are highest in the summer, with cold front and squall line precipitation and with rain showers and thundershowers. All ions measured contributed to sample conductivity but hydrogen ion contributed the most with sulfate ion second. Conductivity calculated from concentrations of the separate ions agreed well with measured conductivity. Conductivity showed relationships to meteorological conditions similar to those of hydrogen ion concentration except when sodium and chloride ions predominated in the sample. 相似文献
502.
Ocón-Grove OM Maddineni S Hendricks GL Elkin RG Proudman JA Ramachandran R 《Domestic animal endocrinology》2007,32(3):201-215
Female mutant restricted ovulator (RO) chickens of the White Leghorn strain carry a naturally occurring single nucleotide mutation in the very low density lipoprotein receptor (VLDLR) gene. Due to this mutation, RO hens fail to express a functional VLDLR protein on the oocyte membrane, which results in an impaired uptake of circulating yolk precursor macromolecules. Mutant RO hens subsequently develop hyperlipidemia and generally fail to lay eggs due to follicular atresia. Since RO hens also reportedly have three-fold higher basal plasma estrogen concentrations, combined with four-fold lower levels of circulating progesterone as compared to wild-type (WT) hens, we hypothesized that RO hens would have an increased abundance of pituitary progesterone receptor (PR) mRNA and PR isoforms A and B as well as alterations in circulating gonadotrophin levels. Quantitative PCR assays revealed significantly greater (P相似文献
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Sanni Y. Doko Pamphile Degla Gilbert O. Edoun Roel H. Bosma 《Tropical animal health and production》2012,45(1):129-134
Low sheep productivity in North Benin hampers economic development, and improvement can contribute to reduction of rural poverty and food insecurity. To reduce one of the constraints to the productivity of Djallonké sheep, high mortality during suckling in full rainy and start dry season, we tested hygienic measures and medication in improved housing. The effect of the two treatments and their combination on lamb performance and the internal rate of return (IRR) were compared to a control. For each treatment, survival and growth were observed in 20 lambs, living in 38 herds. Good housing and hygiene (daily cleaning and fortnightly disinfection of stable and water and feed troughs) reduced mortality and increased growth of suckling lambs until 3 months. Good housing plus medication (unique injection of vitamins and amino acids and with ivermectine for deworming, weekly tick treatment by spraying, and in case of diarrhea, antibiotic treatment) reduced mortality, but growth was not higher than the control. Accounting labor opportunity, the IRR was about equal for both, but capital investment was lower for the hygiene treatment which is thus more accessible to poor farmers. The combination of both treatments increased growth and benefits compared with the hygiene treatment, but decreased the IRR. 相似文献
506.
Bicalho ML Machado VS Oikonomou G Gilbert RO Bicalho RC 《Veterinary microbiology》2012,157(1-2):125-131
The objective of this study was to evaluate the relationship between bacterial species-specific virulence factors (VFs) present in the uterus at 3 different stages of lactation (1-3, 8-10, and 34-36 days in milk (DIM)) and the incidence of metritis and clinical endometritis in dairy cows. The following VF genes were investigated: plo (pyolysin), cbpA (collagen-binding protein), and fimA (fimbriae expression) which are Arcanobacterium pyogenes specific; fimH (a type 1 pilus component), Escherichia coli specific; and lktA (leukotoxin), Fusobacterium necrophorum specific. Uterine swabs were collected from 111 postpartum dairy cows. PCR was used to detect the presence of plo, cbpA, fimA, fimH, and lktA genes. A. pyogenes cbpA was detected in only 5 samples and therefore was not subjected to further analysis. E. coli (fimH) was significantly associated with metritis and endometritis when detected at 1-3 DIM; F. necrophorum (lktA) was significantly associated with metritis when detected at 1-3 and 8-12 DIM and with endometritis when detected at 34-36 DIM; and A. pyogenes (fimA and plo) was associated with metritis (fimA) when detected at 1-3 DIM and endometritis (fimA and plo) when detected at 8-10 and 34-36 DIM. 相似文献
507.
Lysa P Posner J Brett Woodie Paul D Curtis Hollis N Erb Robert Gilbert Wendy A Adams Robin D Gleed 《Journal of zoo and wildlife medicine》2005,36(4):642-647
The objective of this project was to evaluate the acid-base, blood gas, and physiologic parameters of white-tailed deer (Odocoileus virginianus) during laparoscopy in the head-down position. Eleven white-tailed does were captured and then immobilized with xylazine (6 mg/kg i.m.) and ketamine (7 mg/kg i.m.). The deer were intubated orotracheally and maintained with isoflurane in oxygen. The deer were positioned in dorsal recumbency and positive pressure ventilated. Heart rate (HR), arterial blood pressure, end-tidal carbon dioxide concentration (FE/CO2), and CO2 insufflation pressure were recorded every 5 min. Respiratory parameters, plasma electrolytes, and peak inspiratory pressure were measured immediately before tilting deer in the head-down position (45-55 degrees), 5 min after tilting, and immediately before the end of the procedure (while tilted). Butorphanol (0.05 mg/kg i.m.) was administered at the end of the procedure and yohimbine (0.2 mg/kg i.v.) administered before release. The deer weighed 52 kg (28-70 kg) [median (minimum-maximum)]. The peak inspiratory pressure in dorsal recumbency while still horizontal was 25 cm H2O (16-28 cm H2O), which increased to 29 cm H2O (18-46 cm H2O) after tilting (P = 0.02). PaO2, PaCO2, FE/CO2, and pH did not change after tilting in the head-down position or after insufflation. HR did not change during the anesthetic period. Mean arterial pressure did not change after tilting or abdominal insufflation, but decreased by the end of the anesthetic period (approximately 1 hr). Time from intubation to extubation was 117 min (72-170 min) (n = 5) and surgery time was 31 min (17-60 min; n = 10). We conclude that captured white-tailed deer have minimal derangements to acid-base, blood gas, or physiologic parameters during laparoscopy in the head-down position with abdominal insufflation, and thus this procedure may be performed safely in ventilated white-tailed deer. 相似文献
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509.
Two unselected herds of purebred Hereford and Angus cattle were created and their progeny evaluated during a 4-yr period (1964 to 1967) for 168-d postweaning gain when they were fed either a high- or medium-energy diet. Birth weight and 200-d adjusted weaning weight also were measured and the importance of sire x diet interactions for postweaning gain examined. Year effects were significant (P less than .001) for all traits in Herefords and for postweaning gain in Angus. Postweaning gain of both breeds increased in successive years, but no trend was observed for birth and 200-d weights. Bulls were heavier than heifers (P less than .05) for all three traits in both breeds. Hereford and Angus calves receiving the high-energy diet gained more (P less than .001) than their contemporaries fed the medium-energy diet. Sire differences were significant for birth weight in Herefords and for all three traits in Angus. Sire x diet interactions were not significant for postweaning gain in either breed. Genetic correlations were calculated by two methods: the two-way ANOVA approach using sire and sire x diet interaction variance components and the one-way ANOVA approach in which gains by progeny of each sire on each diet were considered to be two distinct traits. The genetic correlations for gain in Herefords could not be estimated by either method because of negative sire variance component estimates. The genetic correlations for gain in Angus were 1.08 for the two-way ANOVA method and 1.43 +/- .64 for the one-way ANOVA method. These results indicate that sires ranked the same based on progeny performance when fed either diet. 相似文献
510.
Samantha Gilbert BVSc BSc MRCVS Harriet Brooks-Brownlie BVetMed Msc PhD MRCVS FRCPath DFMS PGCertAP FHEA Thomas Cardy BSc BVetMed MVetMed PhD DipECVN MRCVS 《Veterinary radiology & ultrasound》2023,64(1):E6-E9
Intravascular lymphoma is a rare presentation of lymphoma with a predilection to the central nervous system (CNS). A 9-year-old male-neutered Collie presented with a 3-month history of lymphadenopathy and a 6-day history of an acute onset, progressive, painful, symmetrical L4-S3 myelopathy. Magnetic resonance imaging revealed multifocal extradural spinal cord compressions from L3 to L6 secondary to a bilaterally enlarged and occluded ventral vertebral venous plexus (VVVP). Histopathology revealed low-grade lymphoma within the venous plexus in the lumbar vertebral column, tracheobronchial lymph nodes, and tonsils. Intravascular lymphoma should be considered a differential diagnosis for enlarged VVVP causing compression of the spinal cord. 相似文献