The duration of lot-feeding of sheep before sea transport

Adult wethers (n = 750) were lot-fed for 13 days, 8 days or 3 days before a simulated voyage lasting 18 days to examine whether the period of lot-feeding affected the proportion of sheep that ate pelleted feed and their body weight change during simulated shipping. There was no significant difference in the proportion of non-feeders between treatment groups on days 7 and 14 of the voyage. Body weights were not significantly different between the treatment groups on days 14 and 18 of the voyage. Overall body weight loss, from the farm to the end of simulated shipping, was 4.08 kg (+/- 0.28, s.e.m.), 4.58 kg (+/- 0.28) and 4.51 kg (+/- 0.28) in sheep lot-fed for 13 days, 8 days and 3 days, respectively, and was not significantly different between treatments. It was concluded that lot-feeding for 13 days conferred no advantage in body weight or numbers of non-feeders compared with shorter periods in this study.     

Correction to: Individual based modelling of fish migration in a 2-D river system: model description and case study

Landscape Ecology - In the original publication of the article, the third author name has been misspelt. The correct name is given in this Correction. The original version of this article was revised.     

In-field calibration of a dielectric soil moisture meter designed for use in an access tube

Abstract. The in-field calibration of a dielectric probe to measure soil water content is described. The probe uses an access tube analogous to that of the neutron probe. The dielectric constant was measured at soil depths of 10, 20, 30, 40, 60 and 100 cm. Cores of soil were then taken from the face of pits dug 30 cm from the access tube and their soil water contents determined by oven drying. The dielectric constant values measured by the probe were calibrated against water contents from these cores. We found that sensor depth needed to be included to achieve a good calibration model that explained 72% of the variance. It is argued that depth needs to be included because of artefacts introduced during the installation of the access tube.     

Effect of oral administration of low doses of pentobarbital on the induction of cytochrome P450 isoforms and cytochrome P450-mediated reactions in immature Beagles

OBJECTIVE: To determine the effect of oral administration of low doses of pentobarbital on cytochrome P450 (CYP) isoforms and CYP-mediated reactions in immature Beagles. ANIMALS: 42 immature (12-week-old) Beagles. PROCEDURE: Dogs were grouped and treated orally as follows for 8 weeks: low-dose pentobarbital (50 microg/d; 4 males, 4 females), mid-dose pentobarbital (150 microg/d; 4 males, 4 females), high-dose pentobarbital (500 microg/d; 4 males, 4 females), positive-pentobarbital control (10 mg/kg/d; 2 males, 2 females), positive-phenobarbital control (10 mg/kg/d; 2 males, 2 females), and negative control (saline 10.9% NaCl] solution; 5 males, 5 females). Serum biochemical and hematologic values were monitored. On necropsy examination, organ weights were determined, and histologic evaluation of tissue sections of liver, kidney, small intestine, testes, epididymis, and ovaries was performed. Hepatic and intestinal drug-metabolizing enzyme activities were measured, and relative amounts of CYP isoforms were determined by western blot analysis. RESULTS: The amount of a hepatic CYP2A-related isoform in dogs from the high-dose pentobarbital treatment group was twice that of dogs from the negative control group. CYP2C was not detectable in small intestinal mucosa of dogs from the negative control group; measurable amounts of CYP2C were found in dogs from the various (low-, mid-, and high-dose) pentobarbital treatment groups and from positive-pentobarbital and positive phenobarbital control groups. Several CYP-mediated reactions increased in a dose-dependent manner. The lowest calculated effective dose of pentobarbital ranged from 200 to 450 microg/d. CONCLUSIONS AND CLINICAL RELEVANCE: Several CYP isoforms and their associated reactions were induced in dogs by oral administration of low amounts of pentobarbital.     

Unguided bronchoalveolar lavage techniques and residual effects in dogs

Objectives To investigate the use of unguided bronchoalveolar lavage techniques in dogs without fibreoptic bronchoscopy, using an adapted single vascular catheter and a double-lumen catheter made from two single vascular catheters.
Animals Sixty-nine dogs were examined with the single-catheter technique and 110 dogs with the double-catheter technique.
Design A prospective study.
Procedure Sixty-nine and 220 samples, collected with the single catheter and the double catheter respectively, were examined cytologically Lungs of 69 dogs were examined grossly and histologically. Radiographic examination was performed on 11 dogs.
Results The double-catheter technique produced samples with significantly higher cellularity (P < 0.01) and fewer red blood cells (P < 0.01) than the single-catheter technique. Repeat samples collected with a double catheter were not significantly different (P > 0.01) in any value. A reference range for nucleated cell counts of 62 to 1210 – 10⁶/L was calculated from 57 clinically and histologically normal dogs. The major residual effects of the technique were localised pulmonary oedema, and alveolar distension with collapse and congestion of distant parenchyma. Thoracic radiographs revealed increased lung opacity for at least up to 7 h after the procedure.
Conclusions The cellularity of the bronchoalveolar lavage fluid obtained was adequate and sufficient fluid was retrieved when the single catheter was located in a proper position. However, the double catheter obtained better samples more quickly and easily, with less damage to the respiratory tract.     

Management of inappetant sheep during export by sea

In the first of 2 experiments, a simulated voyage was conducted to examine the effects of various treatments on bodyweight change and feeding frequency of inappetant sheep at the end of lot-feeding (non-feeders). The treatments, applied during simulated shipping, were: normal quantities of feed and length of troughs; extra trough length; extra feed. Adult Merino wethers (n = 108) were used in each treatment. A voyage to the Middle East was then conducted to establish whether shipboard mortality could be reduced by separating non-feeders (n = 305) from feeders (n = 5,620) late in the feedlot hase and housing the groups separately aboard ship. A control group of non-feeders (n = 215) mixed with feeders (n = 5,732) was used for comparison. Bars (marker bars), containing a coloured dye, were attached to feed troughs to mark sheep that fed. Most non-feeders (82%) began eating when placed in shipping pens in both studies. However, there was no significant difference in percentage of sheep that fed between non-feeders given extra trough length or extra feed compared with non-feeders given standard management at any stage of simulated shipping. There was no significant difference in mean bodyweights between treatment groups on days 1, 8 and 15 of simulated shipping. Differences in bodyweight on d 22 were probably associated with different levels of gut fill. Death rates were not significantly different in separated and control groups (1.1%, 0.9%, P = 0.6) in the voyage of 14 d to the Middle East.(ABSTRACT TRUNCATED AT 250 WORDS)