Effect of a one-off sporidesmin challenge on the milk production of dairy cows     

ZM Matthews  MG Collett  JC Marshall  AC Partridge  PJ Derrick  PJB Edwards 《New Zealand veterinary journal》2018,66(5):261-266

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Retrospective analysis of immunosuppressive and anti-thrombotic protocols in nonassociative immune mediated hemolytic anemia in dogs     

Jennifer Weng  Nyssa A. Levy  Haley Y. Abbott  Jose A. Mix  Robert W. Wills  Andrew J. Mackin  John M. Thomason  Harry Cridge 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2023,37(2):528-536

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Full pedigree quantitative trait locus analysis in commercial pigs using variance components   总被引：1，自引：0，他引：1  

de Koning DJ  Pong-Wong R  Varona L  Evans GJ  Giuffra E  Sanchez A  Plastow G  Noguera JL  Andersson L  Haley CS 《Journal of animal science》2003,81(9):2155-2163

In commercial livestock populations, QTL detection methods often use existing half-sib family structures and ignore additional relationships within and between families. We reanalyzed the data from a large QTL confirmation experiment with 10 pig lines and 10 chromosome regions using identity-by-descent (IBD) scores and variance component analyses. The IBD scores were obtained using a Monte Carlo Markov Chain method, as implemented in the LOKI software, and were used to model a putative QTL in a mixed animal model. The analyses revealed 61 QTL at a nominal 5% level (out of 650 tests). Twenty-seven QTL mapped to areas where QTL have been reported, and eight of these exceeded the threshold to claim confirmed linkage (P < 0.01). Forty-two of the putative QTL were detected previously using half-sib analyses, whereas 46 QTL previously identified by half-sib analyses could not be confirmed using the variance component approach. Some of the differences could be traced back to the underlying assumptions between the two methods. Using a deterministic approach to estimate IBD scores on a subset of the data gave very similar results to LOKI. We have demonstrated the feasibility of applying variance component QTL analysis to a large amount of data, equivalent to a genome scan. In many situations, the deterministic IBD approach offers a fast alternative to LOKI.  相似文献   

Embryonic Loss in Sows with Repeated Propensity for Small Litter Size     

RD Geisert  S Sasakia  AC Clutter 《Reproduction in domestic animals》2007,42(3):333-335

Information is lacking as to the timing and cause of sows that repeatedly have low litter size over several parities. Sows evaluated for the present study had at least two parities either small or=12 (NL) litter size. Following breeding of sows with contemporary boars, reproductive tracts were obtained on day 30 of gestation. There was no difference (p > 0.10) between SL and NL sows in the number of CL, embryo weight or placental length. The total number of embryos and embryonic survival tended to be lower (p < 0.10) in SL sows compared with NL sows, but there were 5.1 less viable embryos (p < 0.03) in SL. Results indicate that time of conceptus loss in SL sows was variable throughout gestation.  相似文献   

The implications of various silvicultural funding arrangements for privately managed public forest land in Canada     

Martin K. Luckert  David Haley 《New Forests》1990,4(1):1-12

When devising policies for financing private silvicultural operations on public forest land, government agencies should consider carefully the benefits and costs of alternative arrangements and how they arc likely to affect tenure holders' behavior. Three general methods of achieving silvicultural objectives arc discussed — the creation of incentives for private voluntary expenditures, reimbursement by governments of expenditures on approved or required silvicultural operations, and required silvicultural operations at the tenure holder's expense.Private firms will only invest voluntarily in silviculture on public lands if they have adequate security of tenure and hold sufficient equity in the timber values resulting from their activities. If firms' silvicultural costs arc reimbursed, their behavior will depend on the extent of reimbursement and whether they have a financial interest in the outcomes of their reimbursed activities. Generally, reimbursement of expenditures must be supported by minimum performance standards and costly monitoring and enforcement procedures. If silvicultural operations are required at the tenure holder's expense, firms will only undertake silviculture to avoid penalties and have a strong incentive to achieve required standards at minimum cost. More stringent monitoring and enforcement procedures may be necessary than if costs arc reimbursed.The impact of policy alternatives is illustrated by means of a survey of silvicultural expenditures on two forest tenure types in British Columbia.  相似文献   

评估调质时间和温度对猪颗粒饲料淀粉糊化度和维生素沉积的影响     

Lewis LL  Stark CR  Fahrenholz AC  Bergstrom JR  Jones CK 《广东饲料》2015,24(5)

本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化  相似文献   

Assessing the influence of mechanical ventilation on blood gases and blood pressure in rattlesnakes          下载免费PDF全文

Mads F Bertelsen  Rasmus Buchanan  Heidi M Jensen  Cleo AC Leite  Augusto S Abe  Søren S Nielsen  Tobias Wang 《Veterinary anaesthesia and analgesia》2015,42(4):386-393

ObjectiveTo characterize the impact of mechanical positive pressure ventilation on heart rate (HR), arterial blood pressure, blood gases, lactate, glucose, sodium, potassium and calcium concentrations in rattlesnakes during anesthesia and the subsequent recovery period.Study designProspective, randomized trial.AnimalsTwenty one fasted adult South American rattlesnakes (Crotalus durissus terrificus).MethodsSnakes were anesthetized with propofol (15 mg kg⁻¹) intravenously, endotracheally intubated and assigned to one of four ventilation regimens: Spontaneous ventilation, or mechanical ventilation at a tidal volume of 30 mL kg⁻¹ at 1 breath every 90 seconds, 5 breaths minute⁻¹, or 15 breaths minute⁻¹. Arterial blood was collected from indwelling catheters at 30, 40, and 60 minutes and 2, 6, and 24 hours following induction of anesthesia and analyzed for pH, PaO₂, PaCO₂, and selected variables. Mean arterial blood pressure (MAP) and HR were recorded at 30, 40, 60 minutes and 24 hours.ResultsSpontaneous ventilation and 1 breath every 90 seconds resulted in a mild hypercapnia (PaCO₂ 22.4 ± 4.3 mmHg [3.0 ± 0.6 kPa] and 24.5 ± 1.6 mmHg [3.3 ± 0.2 kPa], respectively), 5 breaths minute⁻¹ resulted in normocapnia (14.2 ± 2.7 mmHg [1.9 ± 0.4 kPa]), while 15 breaths minute⁻¹ caused marked hypocapnia (8.2 ± 2.5 mmHg [1.1 ± 0.3 kPa]). Following recovery, blood gases of the four groups were similar from 2 hours. Anesthesia, independent of ventilation was associated with significantly elevated glucose, lactate and potassium concentrations compared to values at 24 hours (p < 0.0001). MAP increased significantly with increasing ventilation frequency (p < 0.001). HR did not vary among regimens.Conclusions and clinical relevanceMechanical ventilation had a profound impact on blood gases and blood pressure. The results support the use of mechanical ventilation with a frequency of 1–2 breaths minute⁻¹ at a tidal volume of 30 mL kg⁻¹ during anesthesia in fasted snakes.  相似文献   

Gonadotropin‐induced Puberty Does Not Impair Reproductive Performance of Gilts over Three Parities     

OHO Eckhardt  SMMK Martins  ME Pinese  FC Horta  AC Rosseto  MA Torres  AFC De Andrade  BBD Muro  CT Marino  PHM Rodrigues  AS Moretti 《Reproduction in domestic animals》2014,49(6):964-969

The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty‐nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post‐weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning‐to‐oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation.  相似文献   

Pyramiding genes for resistance to bean common mosaic virus     

J. D. Kelly  L. Afanador  S. D. Haley 《Euphytica》1995,82(3):207-212

Summary Gene pyramiding in Phaseolus vulgaris is being utilized to develop more effective resistance to the temperature-insensitive-necrosis-inducing (TINI) strains of Bean Common Mosaic Virus (BCMV) present in the USA. Our data indicate that contrary to previous work, the bc-3 gene is effective against these strains in the absence of the strain unspecific bc-u gene in genotypes possessing the I gene. The epistatic bc-3 gene interferes with traditional efforts to pyramid the other recessive resistance genes by masking their activity. Indirect selection based on markers linked to the other recessive resistance genes would likewise be ineffective without the ability to also select for the bc-u gene which is required for expression of the bc-2 ² gene in germplasm carrying the I gene. Because the most resistant genotype (I, bc-u, bc-I ², bc-2², bc-3) can only be introduced into a wide range of germplasm through the use of molecular markers linked to the different resistance genes, the search for a marker linked to the strain unspecific bc-u gene should also be given priority.  相似文献   

Antioxidant properties of bran extracts from "Akron" wheat grown at different locations   总被引：3，自引：0，他引：3  

Yu L  Perret J  Harris M  Wilson J  Haley S 《Journal of agricultural and food chemistry》2003,51(6):1566-1570

Bran extracts of Akron wheat grown at four nonirrigated and one irrigated testing locations were examined and compared for their free radical scavenging properties against the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) and the radical cation ABTS(*)(+), chelating capacities, and total phenolic content (TPC) to determine the potential effects of environmental factors on the antioxidant properties of hard winter wheat. The environmental factors included total solar radiation, average daily solar radiation, and number of hours exceeding 32 degrees C. The results showed that bran samples from different growing locations may significantly differ in their radical scavenging activities against both DPPH(*) and ABTS(*)(+), chelating capacities, and TPC. A significant negative correlation was detected between the chelating activities of the bran samples from the four nonirrigated locations and total solar or daily average solar radiation (r = -0.999 and P = 0.001). These data suggest potential influences of growing conditions on the antioxidant properties of hard winter wheat and the possibility of producing wheat that is strong in a selected antioxidant property by optimizing the growing conditions of a selected wheat variety. More research is required to further investigate the relationship among antioxidant properties and environmental factors using different wheat varieties and larger sample sizes.  相似文献