Ultrasound-guided vessel catheterization in adult Yorkshire cross-bred pigs

Objective

To describe an ultrasound-guided approach for venous and arterial vascular access and catheterization in anesthetized adult Yorkshire cross-bred pigs.

Freehand ultrasound-guided femoral arterial catheterization in dogs

Objective: To demonstrate that ultrasound‐guided femoral artery catheterization is feasible and practical in dogs. Case series summary: Four female mixed breed dogs weighing 14–23 kg were used following a terminal junior surgery laboratory and had been anesthetized before the ultrasound study. Dogs were positioned in lateral recumbency with the upper limb abducted and immobilized. The dependent limb was extended and shaved and isopropyl alcohol was applied. An ultrasound transducer was oriented transverse to the axis of the limb and, following ultrasonographic identification, the femoral artery was cannulated and a catheter was placed using the Seldinger technique. Ultrasound‐guided catheterization was successful in 9 of 10 attempts; cannulization was successful in 10 of 10 attempts. Procedure time improved from 10 minutes to 1 minute during practice. Each of the 2 investigators was able to simultaneously ultrasound and cannulate the vessel. The major complication was hematoma formation, which occurred regardless of success. Information provided: Ultrasound‐guided femoral artery catheterization is feasible and relatively easy to master in medium‐size, anesthetized dogs.     

Original Study: Comparison of three intraosseous access techniques in cats

Objective – To compare the placement feasibility and amount of bone trauma induced by 3 intraosseous (IO) access techniques in cats: an automatic impact penetration device (A), an automatic rotary insertion device (B), and a manual IO needle (C). Design – Prospective ex vivo study. Setting – University. Animals – Eighteen adult mixed breed feline cadavers. Interventions – Cadavers provided 72 total IO insertion locations divided equally between the right and left humerus and tibia. The 3 IO techniques were randomly allocated to these locations. Time to successful insertion, ease of insertion, and success rate were recorded. Each insertion site was analyzed for the number of bone fragments and defect diameter by computed tomography. Measurements and Main Results – Device B had lower time of insertion (P=0.01) compared with devices A and C. Device B had better ease of insertion scores (P<0.01) compared with devices A and C. No differences were detected between insertion sites (tibia versus humerus). No differences in the number of bone fragments, defect diameter, or success rate were detected among devices (P=0.06, 0.31, and 0.14, respectively). Conclusions – All 3 IO access methods evaluated yield acceptable results. Device B is significantly faster and easier to place in cat cadavers when compared with other methods.     

Comparison of femoral and auricular arterial blood pressure monitoring in pigs

Objective To compare arterial blood pressure measurements obtained from the femoral and auricular arteries in anaesthetized pigs. Study design Prospective experimental study. Animals Fifteen female Large White pigs were used weighing 21.3 ± 2.3 kg. Methods The pigs were anaesthetized with tiletamine/zolazepam and xylazine administered intramuscularly, and anaesthesia maintained with isoflurane delivered in oxygen/nitrogen. Arterial oxygen partial pressures were maintained between 11.3 and 13.3 kPa and PaCO₂ between 4.6 and 6.0 kPa. Monitoring included electrocardiogram, capnography and invasive blood pressure. The auricular and femoral arteries were catheterized for continuous systolic (SAP), diastolic (DAP) and mean arterial pressure (MAP) measurements. Measurements were recorded every 15 minutes. Statistical analysis involved a Bland–Altman plot analysis. Results The mean difference ± confidence intervals between the femoral and the auricular arterial diastolic, systolic and mean blood pressure measurements during hypotension were 2 ± 7, 2 ± 5 and 2 ± 5 mmHg respectively. In conditions of normotension mean difference ± confidence intervals, of femoral and auricular arterial blood pressure measurements of diastolic, systolic and mean blood pressure were 4 ± 5, 3 ± 7 and 4 ± 4 mmHg respectively. In conditions of increased arterial blood pressure, mean difference ± confidence intervals, of femoral and auricular arterial blood pressure measurements of diastolic, systolic and mean blood pressure were 4 ± 5, 3 ± 8 and 4 ± 4 mmHg respectively. Conclusion Auricular artery catheterization is easier and quicker to perform. Pressure measurements from the auricular artery compared well with the femoral artery. Clinical relevance We found that auricular arterial blood pressures were similar to femoral arterial values under the conditions of this experiment. We did not test extremes of blood pressure or significant alterations in body temperature.     

Comparison of the Bain system and Uniflow universal anaesthetic breathing systems in spontaneously breathing young pigs

OBJECTIVE: To compare minimum fresh gas flow (V(min)) requirements and respiratory resistance in the Uniflow and Bain anaesthetic breathing systems used in the Mapleson D mode. Animals Seven pigs, aged 8-12 weeks, anaesthetized for ophthalmic surgery. MATERIALS AND METHODS: Anaesthesia was maintained with halothane delivered in oxygen using a (Mapleson D) Bain breathing system. The V(min) that prevented re-breathing was found, and peak inspiratory (PIP) and peak expiratory (PEP) pressures measured. The fresh gas flow (V(f)) was then increased to V(min) + 50%, then V(min) + 100%, and respiratory pressures re-measured. A heat and moisture exchanger (HME) was inserted at the endotracheal tube and the procedure repeated. The breathing system was then exchanged for a Uniflow and the protocol repeated. After final disconnection from the breathing system, the animals' peak inspiratory and expiratory flows, tidal, and minute volumes (Vm) were measured over five respiratory cycles. RESULTS: The V(min) (L minute(-1); mL kg(-1) minute(-1)) required to prevent rebreathing in the Uniflow system [8.1(mean) +/-1.7 (SD); 332 +/- 94] was significantly greater than the Bain system (6.5 +/- 1.1; 256 +/- 64). At V(min), PEP with the Uniflow (3.5 +/- 0.1 cm H(2)O) was significantly higher than the Bain system (2 +/- 0.7 cm H(2)O), but PIP values did not differ (Uniflow -0.6 +/- 2.1 cm H(2)O; Bain system -0.2 +/- 0.6 cm H(2)O). With both systems, PEP increased significantly (p < 0.001) with each increase in V(f): Uniflow system 4.2 +/- 0.4 (V(min) + 50%) and 5.5 +/- 0.5 cm H(2)O (V(min) + 100%); Bain system 2.8 +/- 0.7 (V(min) + 50%) and 3.5 +/- 0.7 cm H(2)O (V(min) + 100%). Insertion of the HME did not alter pressures. The mean tidal volume was 6.4 +/- 1.6 mL kg(-1); mean Vm was 184.9 +/- 69.8 mL kg(-1) and mean respiratory rate was 28 +/- 5 breaths minute(-1). In one pig breathing with the Uniflow system PEP rose sharply; respiratory and heart rates increased, and ventricular dysrhythmias occurred. When the system was changed and V(f) reduced, physiological variables became normal. CONCLUSION: The study discredited the hypothesis that the two breathing systems behave similarly. Values for V(min) and PEP were higher with the Uniflow system. Increasing V(f) increased PEP with both systems. Insertion of an HME did not affect respiratory pressures. CLINICAL RELEVANCE: The Uniflow used in Mapleson D mode is not suitable for anaesthesia in young spontaneously breathing pigs.     

Evaluation of transpulmonary ultrasound dilution cardiac output in piglets: accuracy,precision and trending ability with room temperature injectate

ObjectiveTranspulmonary ultrasound dilution (TPUD) is a minimally invasive technique to measure cardiac output (CO) using a 1 mL kg^–1 isotonic 37 °C saline injectate indicator. The objective was to evaluate the performance of TPUD using a room temperature saline injectate.Study designProspective experimental trial.AnimalsA total of seven anesthetized male Yorkshire piglets.MethodsPiglets aged 1 month and weighing 7.7–9.0 kg were anesthetized with detomidine–ketamine–hydromorphone–isoflurane and a pulmonary artery flow probe (PAFP) placed via a median sternotomy. The thoracic cavity remained open during measurement of CO by PAFP and TPUD. The TPUD indicators of 1 mL kg^–1 0.9% saline at 37 °C and 20 °C were compared during infusions of phenylephrine and dobutamine, blood withdrawal and replacement. Bias, limits of agreement (LoAs) and percentage error (PE) between each iteration of PAFP and TPUD were measured with Bland–Altman plots. Trending ability via concordance, angular bias and radial LoA were compared.ResultsBland–Altman plots showed negligible bias with varying LoAs. PEs of 22% and 38% were found for 37 °C and 20 °C saline injectates, respectively. In the four-quadrant plots, the concordance rate was 94% and 100% for measurements obtained with 37 °C and 20 °C saline injectates, respectively. Angular bias for both were < ±5 °, with radial LoA < ±7 °.ConclusionsTPUD was accurate when using 1 mL kg^–1 of isotonic saline at 37 °C in a range of CO within 0.2–0.8 L minute^–1, and it reliably tracked positive and negative changes in CO. Room temperature (20 °C) indicator was less accurate but equally able to track direction of changes in CO.Clinical relevanceThe use of room temperature injectates allows an easy, readily available clinical application of TPUD CO monitoring while preserving the trending ability of the monitor.     

Estimation of direct and social effects of feeding duration in growing pigs using records from automatic feeding stations

Automatic feeding systems in pig production allow for the recording of individual feeding behavior traits, which might be influenced by the social interactions among individuals. This study fitted mixed models to estimate the direct and social effects on visit duration at the feeder of group-housed pigs. The dataset included 74,413 records of each visit duration time (min) event at the automatic feeder from 135 pigs housed in 14 pens. The sequence of visits at the feeder was employed as a proxy for the social interaction between individuals. To estimate animal effects, the direct effect was apportioned to the animal feeding (feeding pig), and the social effect was apportioned to the animal that entered the feeder immediately after the feeding pig left the feeding station (follower). The data were divided into two subsets: “non-immediate replacement” time (NIRT, N = 6,256), where the follower pig occupied the feeder at least 600 s after the feeding pig left the feeder, and “immediate replacement” time (IRT, N= 58,255), where the elapsed time between replacements was less than or equal to 60 s. The marginal posterior distribution of the parameters was obtained by Bayesian method. Using the IRT subset, the posterior mean of the proportion of variance explained by the direct effect (Prpσ^d2) was 18% for all models. The proportion of variance explained by the follower social effect (Prpσ^f2) was 2%, and the residual variance (σ^e2) decreased, suggesting an improved model fit by including the follower effect. Fitting the models with the NIRT subset, the estimate of Prpσ^d2 was 20% but the Prpσ^f2 was almost zero and σ^e2 was identical for all models. For the IRT subset, the predicted best linear unbiased predictor (BLUP) of direct (Direct BLUP) and social (Follower BLUP) random effects on visit duration at the feeder of an animal was calculated. Feeder visit duration time was not correlated with traits, such as weight gain or average feed intake (P > 0.05), whereas for the daily feeder occupation time, the estimated correlation was positive with the Direct BLUP (r^= 0.51, P < 0.05) and negative with the Follower BLUP (r^= −0.26, P < 0.05). The results suggest that the visit duration of an animal at the single-space feeder was influenced by both direct and social effects when the replacement time between visits was less than 1 min. Finally, animals that spent a longer time per day at the feeder seemed to do so by shortening the meal length of the preceding individual at the feeder.     

Investigating maternal effects on production traits in Duroc pigs using animal and sire models

Variance components for production traits were estimated using different models to evaluate maternal effects. Data analysed were records from the South African pig performance testing scheme on 22 224 pigs from 18 herds, tested between 1990 and 2008. The traits analysed were backfat thickness (BFAT), test period weight gain (TPG), lifetime weight gain (LTG), test period feed conversion ratio (FCR) and age at slaughter (AGES). Data analyses were performed by REML procedures in ASREML, where random effects were successively fitted into animal and sire models to produce different models. The first animal model had one random effect, the direct genetic effects, while the additional random effects were maternal genetic and maternal permanent environmental effects. In the sire model, the random effects fitted were sire and maternal grand sire effects. The best model considered the covariance between direct and maternal genetic effects or between sire and maternal grand sire effects. Fitting maternal genetic effects into the animal model reduced total additive variance, while the total additive variance increased when maternal grand sire effects were fitted into the sire model. The correlations between direct and maternal genetic effects were all negative, indicating antagonism between these effects, hence the need to consider both effects in selection programmes. Direct genetic correlations were higher than other correlations, except for maternal genetic correlations of FCR with TPG, LTG and AGES. There has been direct genetic improvement and almost constant maternal ability in production traits as shown by trends for estimated (EBVs) and maternal breeding values (MBVs), while phenotypic trends were similar to those for EBVs. These results suggest that maternal genetic effects should be included in selection programmes for these production traits. Therefore, the animal–maternal model may be the most appropriate model to use when estimating genetic parameters for production traits in this population.     

Comparison of abdominal computed tomography and abdominal ultrasound in sedated dogs

Abdominal ultrasound (US) is used frequently as a first-line screening tool for abdominal disease. Although computed tomography (CT) is superior to US in the diagnosis of some abdominal diseases, a major impediment is the requirement of general anesthesia to prevent motion and for safe restraint. With multidetector helical CT, faster examinations allow general anesthesia to be avoided, while producing diagnostic-quality images. Abdominal US and CT were compared for lesion detection in 27 sedated dogs, divided into three even groups based on body weight. Lesions were categorized further as to subjective clinical relevance. In dogs less than 25 kg, there is no significant difference in lesion detection between CT and US. In dogs weighing greater than 25 kg, more lesions were detected with CT than with US (P = 0.0001), including clinically relevant lesions (P = 0.0277). From these results, it appears that CT has an advantage in lesion detection in dogs greater than 25 kg, making it a better screening test for abdominal disease in these patients.     

Vaccination of feral pigs (Sus scrofa) using iophenoxic acid as a simulated vaccine

OBJECTIVES: To develop an encapsulation method for delivery of vaccines to feral pigs, and quantify the effect of iophenoxic acid on captive feral pig blood iodine concentrations to assist in investigation of factors affecting vaccine uptake. DESIGN AND METHODS: Feral pigs were administered iophenoxic acid by oral gavage, and consumption was assessed for different encapsulation methods in baits. Blood iodine concentrations were monitored for eight days after consumption. The relationship between dose rate, time since dosing and blood iodine concentration was assessed for gavaged and baited captive feral pigs. Wild feral pigs were baited with PIGOUT baits containing 20 mg of encapsulated iophenoxic acid to simulate a vaccination program. Using knowledge from the pen studies, bait uptake and factors affecting bait uptake were investigated. RESULTS: Bait-delivered iophenoxic acid led to variable and inconsistent changes in blood iodine concentrations, in contrast to pigs receiving iophenoxic acid by gavage. This precluded accurate assessment of the quantity consumed, but still allowed a conservative determination of bait uptake. Iophenoxic acid in smaller capsules was consumed readily. Increasing baiting intensity appeared to increase bait uptake by wild feral pigs, and pigs of varying sexes, ages and weights appeared equally likely to consume baits. CONCLUSIONS: Encapsulated liquids can be delivered to feral pigs within baits, should the need to vaccinate feral pigs for fertility or disease management arise. High baiting intensities may be required.     

盐酸多西环素在猪体内的药物动力学及其残留

试验建立了反相高效液相色谱(RT-HPLC)法测定盐酸多西环素的浓度,探讨了盐酸多西环素在猪体内的药物动力学和残留特征。结果表明,盐酸多西环素以2.5mg/kg单剂量肌内注射给猪(n=6),药物动力学模型符合有吸收一室模型,药物动力学参数:吸收半衰期(t1/2ka)、消除半衰期(t1/2ke)为(0.400±0.312)h、(9.530±0.956)h,药时曲线下面积(AUC)为(44.414±4.123)mg·h·L-1,最大血药浓度(Cmax)为(2.811±0.136)mg/L,达峰时间(Tp)为(1.910±0.213)h。另外,以相同剂量肌内注射给猪(n=6),每天1次,连续给药4d后,在不同时间测定盐酸多西环素在猪的肌肉、肝脏、肾脏、皮肤和脂肪中的残留量。在给药后16d,盐酸多西环素在各组织均能检测到,且残留均低于残留限量。盐酸多西环素注射液在猪体内消除缓慢,残留期较长,建议休药期不低于16d。     

Comparison of growth performances,carcass characteristics,and meat qualities of Okinawan indigenous Agu pigs and crossbred pigs sired by Agu or Duroc boar

Indigenous Okinawa Agu pigs are crossed with Large White × Landrace (WL) pigs to improve their meat production, but there is little information regarding the crossbreeding effects. The study aims to compare growth, carcass characteristics, and meat qualities of Agu pigs with those of WL crossbreeds with Agu sires (WLA) or Duroc sires (WLD). WLA pigs showed better growth performance and carcass characteristics and less intramuscular fat (IMF) contents than Agu ones, but they had higher fat deposition, smaller longissimus dorsi muscle area, and higher IMF contents than WLD pigs. Agu pigs showed higher water holding capacity than the other two breeds. The inner layer of Agu backfat contains higher and lower proportions of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acid (PUFA), respectively, than that in WLD animals. WLA animals had intermediate values for the fatty acid content in the inner backfat, although MUFA contents were equal to those of Agu pigs. Fatty acid profiles in IMF were similar to those in the backfat. These results indicate that crossbreeding of Agu with WL pigs improves growth performance and carcass quality. Particularly, WLA pigs have higher IMF contents and MUFA concentrations and lower PUFA concentrations than WLD pigs.     

Excel设计和验证猪浓缩饲料配方图解

文章结合生产实际,用实例演示如何根据猪浓缩饲料产品地方标准、饲料原料营养成分、饲料价格等,利用Excel表设计最低成本猪浓缩饲料配方、验证现有配方。该法具有实用性和可操作性强等优点。     

氟苯尼考在猪的群体药动学

收集临床消化道和呼吸道细菌性疾病猪 2 15头 ,其中原种猪 91头 ,杂交商品猪 12 4头 ;公猪 112头 ,母猪 10 3头 ;体重范围 5～ 4 1kg,平均为 18.6 8± 0 .4 7;日龄 6 3～ 117天 ,平均为 85 .2 4± 0 .78。动物随机分为两组 ,第 1组动物数量为总体数量的 2 / 3,共 14 6头 ,为模型组 ,用于建立群体药动学模型 ;第 2组动物数量为总体动物数量的 1/ 3,共 6 9头 ,为验证组。给药前测定每头猪血清生化指标。试验猪颈部肌肉注射 30 %氟苯尼考注射液 ,剂量为 2 0 mg· kg- 1体重。给药前采一次空白血浆及血清 (测定血清生化指标 ) ,给药后随机采样 ,每只猪采样 2～ 4次 ,就整个群体而言使采样时间均匀分布于药物的吸收相、分布相和消除相内 ,采样时间为给药后 0 .183～ 4 8.36 7h,以高效液相色谱法测定血浆药物浓度 ,应用 NONMEM程序处理所收集的数据 ,包括药时数据、猪只的体重、日龄、性别、种属及血清生化指标、对研究组数据拟合发现最佳药动学模型为一级吸收一室模型 ,药动学参数随机效应及自身变异的最佳模型均为对数加法模型。体重对机体清除率、表观分布容积有显著影响 ,机体清除率、表观分布容积随体重的增加而增加 ,基本呈线性关系。种属对吸收速率常数有显著影响。把研究组得到的群体药动学参数值应用     

The distribution and some pharmacokinetic parameters of ivermectin in pigs

Ivermectin was injected subcutaneously into five pigs at the usual dose rate of 300 µg/kg and found to distribute well to all tissues and body fluids which were sampled 24 h post-injection. Ivermectin was detected in the contents and mucus at all levels of the gastrointestinal tract. The drug was excreted in bile, with high concentrations of the drug in the intestines and faeces. High concentrations of ivermectin were measured in skin, ears and ear wax, suggesting that the drug should be effective in the treatment of ectoparasitic infestations, particularly ear mites. The high lipid solubility of the drug may explain the high concentrations found in ear wax and skin. Ivermectin was also detected in the body fluids and tissues of an untreated pig penned with the treated animals. Direct contact appeared to be necessary for transfer of ivermectin from the treated to the untreated pig but coprophagia or urine drinking is a possible explanation.The pharmacokinetics of ivermectin administered subcutaneously at a dose rate of 300 µg/kg to six pigs were studied. There was marked individual variation in the pharmacokinetics of ivermectin. In one pig the area under the plasma concentration-time curve was particularly high. This may reflect individual variation in uptake and excretion of the drug. The mean elimination half-life of the drug was 35.2 h, suggesting that the drug is cleared slowly from pigs with drug detectable in plasma for 6–10 days. This persistence should allow a short period of protection before re-infection with parasites.     

湘岭猪不同世代、不同屠宰体重胴体性状和肌肉品质测定分析

试验旨在探讨不同世代、不同屠宰体重湘岭猪胴体性状和肌肉品质的差异.试验选择体重140 kg左右的湘岭猪Ⅰ世代阉公猪4头(组4),进行屠宰测定和肉质评定.另选择前期屠宰的零世代14头湘岭猪的屠宰测定数据作为对照,按宰前活重分为3组,分别为90 kg组(组1)、100 kg组(组2)、125 kg组(组3).结果表明:1)...     

猪血浆与组织中地西泮的GC-ECD检测方法

本文对地西泮的 GC- ECD检测方法进行了研究。此方法的样品前处理步骤是 :以乙酸乙酯提取 ,经振荡、离心、浓缩后 ,以 C1 8固相萃取 (solid phase extraction,SPE)小柱净化 ,洗脱液以无水硫酸钠脱水后浓缩 ,残存物以色谱纯正己烷溶解 ,GC- ECD检测。色谱条件为 :载气高纯氮流速为 18psi;进样品温度为 2 90℃ ,检测器温度为 375℃ ,补充气氮气流速为 36 m l·min- 1 ;柱温升温程序为 15 0℃保持 0 .5 min,以每分钟 2 0℃的速度升至 2 6 5℃并保持 10 min。本方法线性范围为 2～ 5 0 0 0 ng/ml(或 ng/ g) ,最低检测限以 3倍信噪比计算为 2 ng/ m l(或 ng/ g) ;地西泮在猪血浆、组织中 GC- ECD分析不同浓度样品的平均回收率分别为 :血浆为 88.7% ,肌肉 76 .7% ,肝脏 88.8% ,肾脏 93.1% ,肺脏 89.4 %。本方法批内、批间变异系数的均值分别为 8.89%和 9.6 1% ,方法的重现性较好。本检测方法具有简便、准确、灵敏 ,线性范围宽、适用性强及有机溶剂污染少等特点 ,为地西泮及其他镇静催眠药在动物血浆及组织中的检测工作提供参考     

Comparison of transcutaneous ultrasound over the right flank with transrectal ultrasound for pregnancy diagnosis in the dairy cow

Objective   Evaluate the sensitivity and specificity of transrectal ultrasound and transcutaneous ultrasonography across the right flank between days 31 and 196 of pregnancy in the dairy cow.
Procedure   Pregnancy status and stage of gestation at date of pregnancy diagnosis by transcutaneous and transrectal ultrasonography were determined for 1570 dairy cattle. Sensitivity and specificity values and probabilities of a correct diagnosis for both techniques were determined and compared. Possible effects of gestational age, herd, method of transcutaneous ultrasound diagnosis, cow age, cow and bull breed, and calf sex on the determination of a correct diagnosis of pregnancy status were evaluated for both techniques.
Results   The overall sensitivity and probability of a correct diagnosis of pregnancy status from days 31 to 196 of gestation were significantly higher when using transrectal ultrasound relative to transcutaneous ultrasound over the right flank. However, the sensitivity of transcutaneous ultrasound changed over the course of pregnancy: it was low (7–8%) before day 84, increased to 89% between days 141 and 154, and was close to 100% thereafter. The specificity of both methods did not differ significantly. Herd and gestational age at date of pregnancy diagnosis were significantly associated with making a correct test result using transcutaneous ultrasound, although only the latter predictor was significantly associated with making a correct test result using transrectal ultrasound.
Conclusion   Transcutaneous ultrasound can not be recommended as an accurate method for early pregnancy diagnosis in the dairy cow, particularly on a whole-herd basis. However, if pregnancy testing is undertaken in mid to late gestation, this technique could provide an accurate and rapid alternative to transrectal ultrasound or manual palpation per rectum.