Effects of xylazine, lignocaine and their combination for lumber epidural analgesia in water buffalo calves (Bubalus bubalis).
The study was conducted to evaluate the effects of xylazine alone (0.05 mg/kg), lignocaine alone (2.0 mg/kg) and a combination of xylazine and lignocaine (0.05 mg/kg and 2.0 mg/kg, respectively) after lumbar epidural administration in water buffalo calves. Fifteen nondescript, male water buffalo calves of 6-8 months of age and weighing between 55 and 75 kg were randomly placed in 3 groups (A, B and C). The agents were administered at the 1st lumbar epidural space. Clinico-physiological parameters such as analgesia, ataxia, sedation, salivation, heart rate, respiratory rate and rectal temperature were studied. Other haematological and biochemical parameters monitored were haemoglobin, packed cell volume, total leukocyte count, plasma glucose, cortisol, protein albumin, globulin, blood urea nitrogen, creatinine, ALT, sodium, potassium and chloride. The onset of analgesia was faster in group C (3.0 +/- 0.44 min) compared with that of group B (4.4 +/- 0.40 min) and group A (34.0 +/- 1.86 min). Analgesia of the thorax, flank, inguinal region, hind limbs, perineum and tail was complete in group C, but mild to moderate in groups A and B. Ataxia was severe in groups B and C and mild in group A. Mild to deep sedation were produced by groups A and C animals. Longer duration and greater depth of analgesia was produced in animals in group C. Heart rate, respiratory rate and rectal temperature decreased in groups A and C. The haematological parameters decreased in all the groups. The biochemical parameters like glucose, cortisol, blood urea nitrogen, creatinine, ALT increased in all the animals. However, total proteins and albumin decreased in the 3 groups. The plasma electrolytes sodium, potassium and chloride did not show any significant change. The results of this study indicated a possible additive analgesic interaction between epidurally administered xylazine and lignocaine, without causing any marked systemic effects in water buffalo calves.
Antinociceptive, sedative and cardiopulmonary effects of subarachnoid and epidural xylazine-lidocaine in xylazine-sedated calves.
OBJECTIVE
To evaluate the antinociceptive, sedative and cardiopulmonary effects of subarachnoid and epidural administration of xylazine-lidocaine in xylazine-sedated calves.


STUDY DESIGN
Prospective, crossover study.


ANIMALS
Six clinically healthy Holstein calves.


MATERIALS
The calves were allocated randomly to receive two treatments, subarachnoid or epidural xylazine (0.025 mg kg(-1))-lidocaine (0.1 mg kg(-1)) diluted to a total volume of 5 mL with physiological saline. Prior to either epidural or subarachnoid injection, sedation was induced in all calves by intravenous administration of 0.1 mg kg(-1) xylazine. The quality and duration of antinociception and sedation were monitored. Areas of the cranial abdomen, umbilicus, and caudal abdomen were evaluated for antinociception using pinprick tests with a scoring system of 0-3 (0, none; 1, mild; 2, moderate; 3, complete). Sedation was assessed by using a 4-point scale (0, none; 1, mild; 2, moderate; 3, deep). The following cardiopulmonary variables were monitored: heart rate (HR), respiratory rate (f(R)), mean arterial pressure (MAP), blood pH, arterial partial pressure of oxygen (PaO(2)), partial pressure of carbon dioxide (PaCO(2)), bicarbonate (HCO(3)), base excess (BE), and oxygen saturation (SaO(2)).


RESULTS
Xylazine sedation and subarachnoid xylazine-lidocaine resulted in significantly higher nociceptive block than the epidural technique. Moreover, subarachnoid xylazine-lidocaine induced a significantly longer duration of complete antinociception (median [IQR]) in the cranial abdomen (15.0 [15.0-30.0] versus 7.5 [1.3-10.0] minutes; p < 0.05) and umbilicus (45.0 [32.5-57.5] versus 10.0 [6.3-17.5] minutes; p < 0.05) compared with epidural xylazine-lidocaine. There was moderate sedation with both techniques. In both treatments, blood pH, MAP and PaO(2) decreased significantly, and PaCO(2) increased significantly during anaesthesia. No change was evident in HR, f(R), HCO(3,) BE, or SaO(2).


CONCLUSION AND CLINICAL RELEVANCE
The subarachnoid injection provided better quality and longer duration of antinociception than epidural administration of the same doses of xylazine-lidocaine in xylazine-sedated calves, while cardiopulmonary depressant effects were observed with both regimens.
Effect of Soybean Cyst Nematode (Heterodera glycines) on Yield of Resistant and Susceptible Soybean Cultivars Grown in Ohio.
Soybean (Glycine max) producers in Ohio rarely use soybean cyst nematode (Heterodera glycines, SCN)-resistant cultivars because of concerns over limited yield potential and lack of resistance to Phytophthora sojae. A two-year study was initiated to determine grain yield and nematode population increase on soybean cyst nematode-resistant cultivars in maturity groups II and III in production fields. Sites differed in soil texture, nematode densities, and P. sojae infestation at a number of locations in Ohio. Soil was assayed for nematode densities before planting and at harvest. Yields of resistant cultivars averaged 0% to 18% higher than those of susceptible cultivars in fine-textured soils with average preplant populations ranging from 463 to 14,330 SCN eggs/100 cm(3) soil. In coarse-textured soils, yields of susceptible cultivars were 21% to 56% less than the resistant cultivars with average preplant densities ranging from 1,661 to 15,558 SCN eggs/100 cm(3) soil. The reproductive index ranged from 0.1 to 5.5 for resistant cultivars and 0.4 to 112 for susceptible cultivars. In 1993, yield of P. sojae-susceptible, nematode-resistant 'Asgrow A 3431' was as high as yield of the P. sojae-resistant, nematode-susceptible cultivar 'Resnik' in a Phytophthora-infested field. The nematode-resistant cultivars Madison Experimental 131527 and Asgrow A3431 had higher yields than AgVenture AV1341 and susceptible cultivars Resnik and Kenwood when compared over five nematode-infested sites. Nematode-resistant cultivars were found to be excellent alternatives to currently grown susceptible cultivars for managing SCN where group III cultivars are used. However, better cultivar alternatives may be needed for sites with combined Phytophthora root rot and cyst nematode problems.