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71.
Acepromazine, a phenothiazine tranquilizer, causes hypotension in standing horses ( Parry et al. 1982 ). However, a retrospective study ( Taylor & Young 1993 ) showed that acepromazine pre‐anesthetic medication did not affect arterial blood pressure (MAP) in anaesthetized horses. This study examined the effects of acepromazine on MAP during romifidine–ketamine–halothane anaesthesia in horses anaesthetized for various surgical procedures. Forty‐four horses were allocated by block randomization to groups A and B. Group A received acepromazine 0.05 mg kg?1 IM 30 minutes before induction of anaesthesia, group B did not. All horses received romifidine 0.1 mg kg?1 IV 5 minutes before anaesthesia was induced with diazepam 0.05 mg kg?1 and 2.2 mg kg?1 ketamine IV. The horses' trachea were intubated and horses breathed 50% oxygen and 50% nitrous oxide plus halothane (concentration adjusted as required clinically) from a circle breathing system. Nitrous oxide was discontinued after 10 minutes and analgesics, flunixin 1.1 mg kg?1 and either morphine 0.1 mg kg?1 or butorphanol 0.05 mg kg?1 (matched for horses undergoing the same procedure) administered IV. The facial or dorsal metatarsal artery was catheterized for direct measurement of MAP (every 10 min) and withdrawal of blood for gas analysis (every 30 min). The electrocardiogram (ECG) was monitored continuously with a 10 seconds printout obtained every 10 minutes. Intermittent positive pressure ventilation (IPPV) was instigated if PaCO2 exceeded 9.3 kPa (70 mm Hg). Dobutamine was infused (1.0–5.0 kg?1minute?1) if MAP < 58 mm Hg and was continued until MAP > 70 mm Hg. Mean age, weight and duration of anaesthesia were compared between the groups using a t‐test for independent samples. Gender distribution and numbers of horses requiring IPPV or dobutamine were compared between groups using a chi‐squared test (with Yates correction). To compare MAP over time, the area under the curve (MAPAUC) was calculated and compared between groups using a t‐test. Horses receiving dobutamine were excluded from MAPAUC and MAP comparisons. The ECG printouts were examined for arrhythmias. There were no significant differences between groups (p > 0.05). Group A contained three stallions, 10 geldings and nine mares, aged 6.3 years (range 0.75–18). Group B comprised eight stallions, 11 geldings and three mares aged 7.3(1–16) years. Duration of anaesthesia was group A 97 (50–140) minutes, group B 99 (50–160) minutes. Eight horses in group A and three in group B required IPPV. Nine horses in group A and four in group B received dobutamine. Mean arterial pressure ranged from 60 to 128 mm Hg in group A and 58–96 mm Hg in group B. Mean MAPAUC was 5941 mm Hg minute?1 in group A, in B 6000 mm Hg minute?1. Atrial pre‐mature complexes were recorded from one horse in group B. No other arrhythmias were detected. Although MAP was lower in the acepromazine group, this appeared unlikely to cause a clinical problem. The incidence of arrhythmias was too low to determine the influence of acepromazine in this study. 相似文献
72.
M. LE CORRE P. ALEXANDRINO M. R. SABATIE M. W. APRAHAMIAN & J. L. BAGLINIÈRE 《Fisheries Management and Ecology》2005,12(4):275-282
Abstract Data on the genetic characteristics of the rhodanian shad, Alosa fallax rhodanensis Roule, using three Mediterranean populations (rivers Rhône, Aude and Hérault) and seven protein markers are presented. Allelic frequency distribution, and absolute and relative genetic diversity show a genetically homogeneous structure in the Mediterranean populations. Results when compared with allis ( Alosa alosa Linné) and twaite ( Alosa fallax fallax Lacépède) shad Atlantic populations confirm that the Rhodanian shad belongs to the Alosa fallax Roule species. Furthermore, genetic characteristics of the twaite shad Mediterranean group were quite different from Atlantic populations but remained close to the most southern Atlantic population in the Oued Sebou (Morocco). These findings suggest that Rhodanian shad should be considered a well identified homogeneous group within Alosa fallax rather than a subspecies because of the low genetic distance and some relatively different biological characteristics between the Atlantic and Mediterranean twaite shad groups. 相似文献
73.
Haploids were extracted from 66 differentSolanum tuberosum Group Andigena introductions usingS. tuberosum Group Phureja clone 1.22 as pollinator. The overall frequency of haploids was 13 per 100 fruit, with a high of 106. The overall average number of seeds per fruit was 1.4. Some Group Andigena clones produced primarily haploid, others primarily triploid, and still others primarily tetraploid progeny. The “triploid block” is still evident in these materials even though some clones produce primarily triploid progeny. It is suggested that the ploidy level of progeny produced in 4x - 2x crosses may be under relatively simple genetic control. 相似文献
74.
Two thousand and fifty-five pollinations were made between the cultivar Russet Burbank and Group Phureja pollinator clone 1.22, resulting in 882 fruit and 253 seeds. One-hundred and fifty progeny grew from these seeds, of which 6 were haploids, 143 were triploids and 1 was tetraploid. None of the haploids flowered. The predominance of triploids was unusual for Gp. Tuberosum cultivars, but it does not indicate a breakdown of the “triploid block” because of the low seed set. These results are similar to those found during haploid extraction from Gp. Andigena, suggesting the possibility that Gp. Andigena may have been involved in the parentage of Russet Burbank. 相似文献
75.
76.
R. E. Hanneman Jr 《Potato Research》1999,42(2):283-312
Summary Haploidy, 2n gametes, synaptic mutants, stylar barriers, endosperm barriers. Endosperm Balance Number (EBN) and its relationship
to 2n gametes, stylar barriers and disomic genetics are a part of the reproductive biology of potato. Also all are tools for
isolation and preservation of a species identity. Haploidy and 2n gametes allow for interploidy gene transfer. Parallel spindles
and synaptic mutants permit the transfer of entire parental genomes intact and are powerful tools in potato breeding. Stylar
barriers provide a mechanism for interspecific isolation via unilateral incompatibility. Incongruity has also been invoked.
Endosperm barriers have been discussed in terms of EBN which requires a 2 maternal:1 paternal ratio in the endosperm for successful
seed development. Genetic models suggesting three unlinked genes in a threshold-like system and a two gene system have been
proposed. A relationship may exist between EBN and stylar barriers. The use and manipulation of 2n gametes, stylar barriers
and EBN have been used effectively in germplasm transfer from species to cultivated potato.
Note: This paper is dedicated to Dr S.J. Peloquin, Emeritus Professor, Department of Horticulture, University of Wisconsin-Madison,
a mentor, friend and colleague, in recognition of the enormous contributions he has made to this area and for his enthusiasm
for and stimulation of others to an awareness of the importance of its application to plant improvement.
Cooperative investigation of the Vegetable Crops Research Unit, United States Department of Agriculture, Agricultural Research
Service and the Wisconsin Agricultural Experiment Station. 相似文献
77.
RC Handcock N Lopez-Villalobos LR McNaughton PJ Back GR Edwards RE Hickson 《New Zealand veterinary journal》2020,68(5):272-282
ABSTRACT Aims: To examine the relationship between liveweight (LWT) at 12 months as a proportion of LWT at 21 months of age (LWT(12/21)%) and first lactation and cumulative 3-year milk production in dairy heifers in New Zealand. Methods: Liveweight and milk production records were obtained for dairy heifers born from June to December (spring-calving season) between 2006–2007 and 2013–2014 dairy seasons; production records included first lactation (n?=?140,113) and cumulative 3-year (n?=?67,833) milksolids and energy-corrected milk (ECM) yields. Heifers were classified into five breed groups; Holstein-Friesian, Holstein-Friesian crossbred, Jersey, Jersey crossbred and Holstein-Friesian-Jersey crossbred. Within each breed group heifers were categorised into quintiles based on 21-month LWT. The LWT(12/21)% was calculated for each animal. Relationships between LWT(12/21)% and milk production within each breed group and LWT category were estimated using linear mixed effects models including the linear and quadratic effects of LWT(12/21)%. Results: The relationship between LWT(12/21)% and milk production was predominantly curvilinear, with lower milk production at lesser LWT(12/21)% compared with greater LWT(12/21)%. For all breed groups and most LWT categories, heifers that were 55 or 65% LWT(12/21)% produced greater ECM and milksolids yields compared with heifers that were 45% LWT(12/21)%. Holstein-Friesian, Holstein-Friesian crossbred and Holstein-Friesian-Jersey crossbred heifers that were 65% LWT(12/21)% produced greater cumulative 3-year ECM and milksolids yields compared with heifers of the same breed group that were 45% LWT(12/21)% Conclusions and clinical relevance: Heifers that were a greater proportion of their 21-month LWT at 12 months of age produced more first lactation and cumulative 3-year milk yields than heifers that were a lesser proportion of their 21-month LWT at 12 months of age. These results indicate that increased growth in early life of New Zealand dairy heifers is beneficial to future milk production. 相似文献
78.
LAURA H. JAVSICAS VMD Diplomate ACVIM STEEVE GIGUÈRE DVM PhD Diplomate ACVIM DAVID E. FREEMAN MVB PhD Diplomate ACVS DWAYNE H. RODGERSON DVM MS Diplomate ACVS NATHAN M. SLOVIS DVM Diplomate ACVIM 《Veterinary surgery : VS》2010,39(2):254-260
Objective— To determine outcome after medical or surgical treatment of postpartum mares with confirmed or presumptive uterine tears. Study Design— Case series. Methods— Postpartum mares were included if foaling had occurred within 7 days and uterine tear was confirmed surgically or, in medically treated mares, by palpation or presumed based on peritonitis. Information (age, breed; physical examination, laboratory and abdominocentesis findings; treatment, survival rates, length of hospital stay, treatments costs, and breeding performance after discharge) was obtained from the medical records (1990–2007). The influence of variables was compared between medical and surgical treatment, and between survivors and nonsurvivors. Results— For 49 mares, survival was 75%, with no significant difference between medical (11/15; 73%) or surgical (26/34; 76%) treatment. Admission variables, treatment cost, duration of hospital stay, and likelihood of foaling after discharge were not significantly different between treatment groups. Nonsurvivors were significantly more likely to have gastric reflux, higher heart rate, anion gap, lower total CO2, and leukocyte count, compared with survivors. Tears were significantly (P=.018) more likely to occur in the right uterine horn than in other parts of the uterus. Conclusions— Uterine tears occur more commonly in the uterine horns, more so the right horn, and survival is similar with surgical or medical treatment of uterine tears in postpartum mares. Clinical Relevance— Medical treatment may be a reasonable alternative to surgical treatment for uterine tears, although the severity of tear that can resolve with medical treatment is unknown, and medical therapy can be as expensive as surgical treatment. 相似文献
79.
Ultrasound during mid‐gestation: Agreement with physical foetal and placental measurements and use in predicting gestational age in sheep 下载免费PDF全文
AK Jones RE Gately KK McFadden ML Hoffman SM Pillai SA Zinn KE Govoni SA Reed 《Reproduction in domestic animals》2017,52(4):649-654
To determine the effects of poor maternal nutrition and litter size on foetal growth during mid‐gestation, pregnant ewes (n = 82) were fed 100%, 60% or 140% of NRC TDN beginning at day 30.2 ± 0.2 of gestation. Transabdominal ultrasound was performed weekly between day 46.0 ± 0.4 and 86.0 ± 0.7 to monitor foetal heart width (HW), umbilical diameter (UMB), rib width (RW) and placentome outer (OD) and inner diameter (ID). Data were analysed with repeated‐measures using the mixed procedure for effects of maternal diet, litter size and gestation, and equations predictive of gestational age were generated using the regression procedure. To determine the agreement of ultrasound measurement and actual size, ewes (n = 20–21) were euthanized at day 45 or 90 to obtain corresponding postmortem measurements for Bland–Altman analysis. The HW, UMB and placentome OD and ID increased with gestation (p < .0001) but were unaffected by maternal diet or litter size (p ≥ .12). Ultrasound underestimated postmortem measurements of HW (14.8%), UMB (7.3%), placentome OD (4.5%) and ID (37.3%) at day 90 of gestation. Ultrasound underestimated RW at day 45 (7.7%) but overestimated RW (23.8%) at day 90, indicating inconsistent bias when reporting RW by ultrasound. Combining the HW, UMB, RW and placentome OD generated the strongest equation predictive of gestational age (R2 = .91). These findings indicate that during mid‐gestation, maternal diet or litter size did not affect HW, UMB or placentome diameters and these factors can be used to estimate gestational age. 相似文献
80.