Effect of diets containing sulfate or chloride-based anionic salts,fed to grazing prepartum dairy cows,on concentrations of Ca in plasma,disease incidence and milk yield     

P Melendez  V Zaror  P Gaul  SE Poock  JP Goff 《New Zealand veterinary journal》2019,67(2):79-85

AIMS: To compare the effect of two partial mixed ration diets containing either sulfate or chloride-based anionic salts, fed to grazing prepartum dairy cows, on concentrations of Ca, Mg, P and beta-hydroxybutyrate (BHB) in plasma, disease incidence and milk yield during the early postpartum period.

METHODS: The study was conducted on a seasonal-calving grazing dairy farm located in Benton (MO, USA). In August 2016, two groups of 200 cows were randomly assigned at 30 days before expected parturition to receive either a sulfate or chloride-based anionic diet, to achieve a dietary cation–anion difference (DCAD) of ?25?mEq/kg DM. Cows were fed partial mixed rations to provide 50% of their DM intake, with 50% provided by grazing fescue pasture. Urine samples were collected from 20 cows from each group once a week for 5 weeks until calving for pH assessment. At parturition, 42 cows per group were selected at random and blood samples collected on Days 1, 2, 3 and 7 postpartum. The study continued until 100 cows per group calved. Health events and cumulative milk yield until 30 days postpartum were recorded. Concentrations of Ca, P, and Mg in plasma at Days 1, 2, 3, and 7, and BHB in plasma at Day 7 postpartum were assessed.

RESULTS: Mean urine pH was lower in cows in the chloride than sulfate group (p≤0.06) on four of five sampling occasions. Mean concentrations of Ca in plasma on Day 1 were 2.00 (95% CI=1.94–2.05) and 1.91 (95% CI=1.88–1.97) mmol/L for the chloride and sulfate groups, respectively (p=0.15), and on Day 3 were 2.03 (95% CI=1.97–2.08) and 1.90 (95% CI=1.84–1.96) mmol/L, respectively (p=0.038). Concentrations of Mg, P and BHB in plasma and incidence of diseases postpartum were similar in both groups (p>0.05). There were no cases of clinical hypocalcaemia in either group.

CONCLUSIONS AND CLINICAL RELEVANCE: Prepartum cows fed a partial mixed ration with a negative DCAD containing chloride-based anionic salts and free access to a fescue pasture had lower prepartum urine pH, and higher concentrations of total Ca in plasma during the first week postpartum, than cows receiving a partial mixed ration containing sulfate-based anionic salts.  相似文献   

Thalidomide pharmacokinetics in sheep     

SL Smith  P Singh  D Harding  D Lun  JP Chambers 《New Zealand veterinary journal》2016,64(4):238-242

AIM: To determine the half life (T_1/2), time taken to reach maximum plasma concentration (T_max) and maximum plasma concentration (C_max) of thalidomide in sheep following I/V, oral and topical treatment with a single dose of thalidomide.

METHOD: Three groups of 4–6-month-old ram lambs were treated with thalidomide dissolved in dimethylsulphoxide (DMSO). The first group (n=10) was treated I/V with 100?mg thalidomide in 2?mL DMSO; the second group (n=8) received 400?mg thalidomide in 2?mL DMSO orally, and the third group (n=8) had 400?mg thalidomide in 4?mL DMSO applied topically. Plasma samples were collected up to 36 hours after treatment, snap-frozen at ?80°C and analysed for concentrations of thalidomide using high performance liquid chromatography.

RESULTS: Following I/V administration, T_1/2 was 5.0 (SEM 0.4) hours, volume of distribution was 3,372.0 (SEM 244.3) mL/kg and clearance was 487.1 (SEM 46.1) mL/hour.kg. Topical application of 400?mg thalidomide did not increase plasma concentrations. Following oral administration, thalidomide bioavailability was 89%, with T_1/2, T_max, and C_max being 7.2 (SEM 0.8) hours, 3.0 (SEM 0.4) hours and 1,767.3 (SEM 178.1) ng/mL, respectively.

CONCLUSION: Topical administration using DMSO as a solvent did not increase concentrations of thalidomide in plasma. The mean pharmacokinetic parameters determined following oral treatment with 400?mg of thalidomide were similar to those reported in humans receiving a single 400?mg oral dose (T_1/2 7.3 hours; T_max 4.3 hours and C_max 2,820?ng/mL). There is potential for thalidomide to be used as a model for the treatment of chronic inflammatory conditions in sheep, such as Johne's disease, where tumour necrosis factor alpha plays a pathogenic role.  相似文献   

Evaluation of action thresholds for chronic rice insect pests in the Philippines. I. Less frequently occurring pests and overall assessment     

JA Litsinger  JP Bandong  BL Canapi  CG Dela Cruz  PC Pantua  AL Alviola 《国际虫害防治杂志》2013,59(1):45-61

Action thresholds as decision tools for insecticide application were developed and tested against the major insect pests of rice at four sites in the Philippines over a 13-year period. Action threshold treatments were compared to the farmers' practice, prophylactic insecticide usage, and an untreated check. Yield loss data using the insecticide check method partitioned yield losses over three crop growth stages in the same test fields. Chronic pests that exceeded action thresholds in 79% of fields were whorl maggot Hydrellia philippina Ferino (Diptera: Ephydridae), defoliators Naranga aenescens Moore and Rivula atimeta (Swinhoe) (Lepidoptera: Noctuidae), leaffolders Cnaphalocrocis medinalis (Guenée) and Marasmia patnalis Bradley (Lepidoptera: Pyralidae), and stemborers Scirpophaga incertulas (Walker) and S. innotata (Walker) (Lepidoptera: Pyralidae). Minor chronic pests reached threshold levels in only one site each: rice bug Leptocorisa oratorius (F.) (Koronadal), whitebacked planthopper Sogatella furcifera (Horvath) (Zaragoza) and green leafhopper Nephotettix virescens (Distant) (Guimba); brown planthopper Nilaparvata lugens (Stål) did not exceed a threshold in any field. Stemborers were the most important pest group in terms of yield loss. Despite the insecticide check method underestimating losses, a mean crop loss of 0.62 t/ha was measured which showed ample scope for corrective action. But loss was evenly distributed across crop growth stages (0.15?–?0.24 t/ha) reducing the impact of insecticides. Action threshold treatments overall outyielded the untreated check, more so in the two sites with highest pest density. The benefit of thresholds was to reduce insecticide usage, as a cost saving. However all the practices showed poor economic returns including the farmers' practice. Farmers' practice employed low insecticide dosages and timing was not consistent with pest damage, but yields were often similar to threshold treatments. Farmers appear to use insecticide more for risk aversion than for profit. The best threshold characters when evaluated against resulting pest density and yield loss criteria showed accuracies >?90% correct decisions. Future work is needed to improve the insecticide response rather than monitoring tools. Thresholds need to be incorporated into improved crop management, which was often found suboptimal by farmers, to take advantage of the high levels of tolerance in modern high tillering cultivars. Crop husbandry practices which improve yield potential such as selection of longer maturing varieties and nitrogen fertilizer may be a more effective pest management strategy than insecticides.  相似文献   

The influence of weather on the population dynamics of the rice stink bug and the implications for integrated pest management     

JP Sutherland  V Baharally 《国际虫害防治杂志》2013,59(4):335-342

The influence of weather on the population dynamics of Oebalus poecilus, the principal insect pest of rice in South and Central America, is examined. Light trapping was used for one year, but was soon discarded in favour of the more reliable sweep netting which was utilised to monitor populations in fields and non-cropped habitats from autumn 1999 to spring 2002. The results indicate that O. poecilus feeds on alternative host grasses on levées surrounding the rice fields. Adult bugs move into the fields in mid-January and mid-August of each year. In fields there are typically four generations per season, which are approximately four weeks apart. Adults move off the crop in April and October. Data presented here indicate that rainfall is critical to the ‘off-season’ survival of O. poecilus, and high rainfall during April to July and November to January causes increases in O. poecilus populations. This is particularly important given the recent extreme perturbations in the normal bimodal rainfall patterns caused by El Niño and La Niña events. The ability to predict the severity of O. poecilus populations from weekly rainfall data will provide a significant input into the development of IPM programme for O. poecilus.  相似文献   

Cattle herd inspections and fly trapping for the detection of the Old World screw‐worm fly (Chrysomya bezziana)     

R Urech  S Muharsini  RS Tozer  Sumartono  PE Green  GW Brown  JP Spradbery  DG Mayer  Y Tack Kan  A Kison 《Australian veterinary journal》2014,92(1-2):28-32

  相似文献   

Effect of Taurine and Melatonin in the Culture Medium on Buffalo In Vitro Embryo Development     

BM Manjunatha  M Devaraj  PSP Gupta  JP Ravindra  S Nandi 《Reproduction in domestic animals》2009,44(1):12-16

This study was carried out to investigate the effect of supplementing culture medium with different concentrations of taurine and melatonin, on buffalo oocyte in vitro meiotic maturation and embryo development. In experiment 1, oocytes were matured in vitro and the cleaved embryos were cultured in the same following seven culture medium; (i) control (TCM 199 + 10% SS); (ii) control + 0.5 m m taurine; (iii) control + 1 m m taurine; (iv) control + 3 m m taurine; (v) control + 5 μ m melatonin; (vi) control + 10 μ m melatonin and (vii) control + 50 μ m melatonin. In experiment 2, based on the results of experiment 1, to examine the synergistic effect of antioxidants, the oocytes were matured in culture medium (TCM199 + 10% SS), supplemented with both taurine at 1 m m and melatonin at 10 μ m concentration and the cleaved embryos were cultured in the same medium. Supplementation of taurine at 1 m m concentration in the culture medium resulted in a higher (p < 0.05) transferable embryo (TE) yield when compared with control (20.6% vs 14.1%). Supplementation of melatonin at 10 and 50 μ m concentration in the culture medium resulted in a higher (p < 0.05) meiotic maturation rate (90.3% and 88.8% respectively) and TE yield (28.4% and 27.2% respectively), than the other treatments. In experiment 2, the TE yield did not improve by supplementing the culture medium with both taurine and melatonin, when compared with melatonin alone. In conclusion, the results of this study demonstrated that, enriching the culture medium with taurine and melatonin, improves in vitro embryo production efficiency in buffaloes. In particular, a high TE yield was obtained by enriching the culture medium with 10 μ m melatonin.  相似文献   

Neospora caninum infection in dogs     

BL MUNDAY  JP DUBEY  RW MASON 《Australian veterinary journal》1990,67(2):76-77

  相似文献   

Detection of Follicular Apoptosis in Water Buffalo (Bubalus bubalis) Ovary by Histology and Nick End Labelling Technique     

P Sreejalekshmi  BS Raghavendra  T Siva Subramani  V Chandrashekara Murthy  KV Jamuna  RV Prasad  JP Ravindra  S Selvaraju 《Reproduction in domestic animals》2011,46(1):59-65

The objective of this experiment was to assess the features and extent of follicular apoptosis in the water buffalo (Bubalus bubalis) ovary using classical histology and nick end labelling technique. Ovaries (n = 40) procured from the slaughterhouse were used for the study. The sections (5 μm) were used for detection of terminal deoxynucleotidyl transferase‐mediated dUTP‐biotin nick end labelling (TUNEL) and classical histology (H&E). Those follicles showing ≥ 5% TUNEL positivity (TUNEL assay) and pyknotic nuclei (histology) in granulosa cells were classified as atretic. Based on histology, the atretic primary and secondary follicles (%) were 93.82 and 95.62 respectively. The histology study reveals that the rates (%) of atresia in <1, 1–3, 3–5 mm and >5 mm were 36.90, 40.50, 62.84 and 74.5 respectively. Further the atretic tertiary follicles (%) were significantly lower than the primary and secondary classes of follicles. TUNEL assay reveals that the atretic rate (%) of tertiary follicles in <1, 1–3, 3–5 and ≥ 5 mm class follicles were 50.88, 53.84, 81.81 and 36.36 respectively. The percentage of atresia in >5 mm diameter follicles were significantly lower in TUNEL than histology. Percentages of granulosa and thecal cells positive for atresia by TUNEL were 30.7 ± 0.53 and 13.82 ± 0.18 respectively per follicle. The initial structural changes in atretic follicles were seen primarily in the granulosa cells. In severely atretic follicles TUNEL positive granulosa cells along with theca cells have to be considered in assessing the rate and extent of atresia.  相似文献   

Molecular Basis of Gene-for-Gene Specificity in Bacterial Speck Disease of Tomato   总被引：6，自引：0，他引：6  

SR Scofield  CM Tobias  JP Rathjen  JH Chang  DT Lavelle  RW Michelmore  BJ Staskawicz 《Science (New York, N.Y.)》1996,274(5295):2063-2065

Transient expression of the Pseudomonas syringae avirulence gene avrPto in plant cells resulted in a Pto-dependent necrosis. The AvrPto avirulence protein was observed to interact directly with the Pto resistance protein in the yeast two-hybrid system. Mutations in the Pto and avrPto genes which reduce in vivo activity had parallel effects on association in the two-hybrid assay. These data suggest that during infection the pathogen delivers AvrPto into the plant host cell and that resistance is specified by direct interaction of Pto with AvrPto.  相似文献   

Allele frequency of hereditary equine regional dermal asthenia in American Quarter horses in Brazil determined by quantitative real-time PCR with high resolution melting analysis     

Peres R. Badial  José P. Oliveira-Filho  Nena J. Winand  Alexandre S. Borges 《Veterinary journal (London, England : 1997)》2014,199(2):306-307

Hereditary equine regional dermal asthenia (HERDA) is a genetic disorder that occurs in the American Quarter horse (AQH) and is caused by a c.115G>A missense mutation in the peptidylprolyl isomerase B (PPIB) gene. Using a quantitative real-time PCR high resolution melting analysis genotyping assay for the PPIB mutation, the estimated HERDA allele and carrier frequencies in a sample of Brazilian AQHs were 2.9% and 5.8%, respectively.  相似文献