The metabolite products of chlorocholine chloride (CCC) in eggs and meat of laying hens fed 15N-CCC containing diets

An experiment was conducted to evaluate the metabolic products of chlorocholine chloride (CCC) in eggs and meat of laying hens fed a diet containing (15)N-CCC. Ten brown laying hens were randomly divided into two groups of five each. One group was offered (15)N-CCC free diet while the other group received a diet with 100 ppm (15)N-CCC for 11 days. Samples of eggs and meat from the laying hens were collected. Egg yolks and albumen were separated. Meat was collected from the breast and femur. The metabolic products of CCC were measured using ion trap electrospray ionisation mass spectrometry (ion trap-ESI-MS/MS). Determination of CCC or its metabolites in eggs and meat showed that CCC was metabolised to choline. Corresponding MS/MS spectra were obtained for m/z 104 (choline) or 105 ((15)N-choline), whereas nothing was detected at m/z 122 (CCC) or 123 ((15)N-CCC). The results from this study indicate that CCC will be metabolised in tissues of laying hens.     

Glanders--a comprehensive review

Since 1990 the number of glanders outbreaks in race, military and pleasure horses in Asia and South America is steadily increasing. Glanders, which is eradicated in Western Europe, Australia and Northern America, is currently considered a re-emerging disease. Consequently, the disease may be introduced into glanders-free regions by subclinical carriers at any time. The causative agent of glanders, Burkholderia (B.) mallei, is highly contagious and leads to chronic disease in horses whereas in donkeys and mules the disease is acute and often fatal. Occurrence of the disease leads to international trading restrictions and infected animals immediately have to be culled and safely disposed off. In humans B. mallei infection results in a severe clinical course, and is fatal without appropriate therapy. Its pathogenicity makes B. mallei a potential biological agent that may be used in bioterroristic attacks. Due to the eradication of glanders in the second half of the last century, veterinarians in western European countries are no longer familiar with its clinical presentation in solipeds. Having these facts in mind, this review describes the epidemiology, clinical signs, pathology and the current eradication strategy of this interesting zoonosis. Pictures of imported endurance horses infected with glanders taken during an eradication campaign in Dubai, United Arab Emirates, in 2004 illustrate most typical clinical findings.     

Wet corn gluten feed and alfalfa hay levels in dry-rolled corn finishing diets: effects on finishing performance and feedlot nitrogen mass balance

One-hundred ninety-two crossbred steers (initial BW = 351 +/- 11 kg) were used to determine the effects of removing alfalfa hay (AH) from dry-rolled corn-based diets containing wet corn gluten feed (WCGF) on animal performance and nutrient (N and OM) mass balance in open feedlot pens. Steers were stratified by weight and assigned randomly to 24 pens (2 x 3 factorial) and fed for 132 d from June to October 2002. Experimental diets contained either 0 or 35% WCGF and 0, 3.75, or 7.5% AH, and were formulated to be isonitrogenous. For efficiency of gain, an interaction occurred (P = 0.09) between AH and WCGF. Feed efficiencies of cattle fed 35% WCGF were improved 4.4% (P = 0.10) compared with efficiencies of cattle fed no WCGF at 0% AH; there was a marked improvement in ADG for cattle fed WCGF compared with no WCGF in diets with 0% AH. Within 35% WCGF diets, efficiency decreased as AH inclusion increased (P = 0.06). Efficiency was equal across AH levels when 0% WCGF was fed; however, ADG was decreased when AH was removed. Interactions between AH and WCGF were not detected for other performance or carcass criteria; therefore, main effects of AH and WCGF are discussed. Daily intake, ADG, and HCW increased linearly (P < 0.05) as dietary AH level increased. Feeding 35% WCGF also resulted in greater DMI (P < 0.01) and a tendency for greater ADG and HCW (P < or = 0.10) compared with steers fed no WCGF. Interactions between AH and WCGF were not observed for feedlot N mass balance. As level of AH increased across diets, N intake, N retention, and N excretion increased (P < 0.05). Steers fed 35% WCGF consumed and excreted more N (P < 0.01) than those fed no WCGF. More manure DM (P = 0.11), OM, and N (P < 0.01) were removed from pens housing steers fed 35% WCGF as well as greater OM and N recovery in finished compost. More N (kilogram/steer) was also lost to volatilization as a result of greater N excretion when WCGF was fed. Expressed as a percentage of N excretion, loss of N from pens housing steers fed 0 and 35% WCGF was not different, averaging nearly 80%. These data suggest that AH has less value when dry-rolled corn-based diets contain 35% WCGF and can be decreased from conventional levels. Furthermore, loss of N from open feedlot pens is high during the summer months, and feeding WCGF may not reduce N losses during these times of year.     

Dietary supplementation with sodium bicarbonate improves calcium absorption and eggshell quality of laying hens during peak production

1. The advantage of supplemental sodium bicarbonate (NaHCO₃) on eggshell quality in laying hens changes with age. Besides increasing calcium (Ca) secretion in the eggshell gland, it may improve Ca absorption in the intestine or kidney.

2. Hy-Line Brown layers (n = 384), 25 weeks of age, were allocated to two treatment groups in two experiments, each of which included 4 replicates of 24 hens. Hens were fed a basal diet (control) or the basal diet containing 3 g NaHCO₃ g/kg for 50 or 20 weeks in Experiment 1 or 2, respectively. A 24-h continuous lighting regimen was used to allow hens to consume the dietary supplements during the period of active eggshell formation.

3. In Experiment 1, particularly from 25 to 50 weeks of age, and in Experiment 2, NaHCO₃ supplementation favoured hen-d egg production at the expense of lower egg weight. The increased eggshell thickness should have nothing to do with the additional eggshell formation, because of the unchanged egg mass and daily eggshell calcification.

4. At 35 weeks of age in both experiments, NaHCO₃ supplementation increased duodenal expression of calbindin-d28k (CaBP-D28k) protein, contributing to higher Ca retention and balance.

5. From 50 to 75 weeks of age in Experiment 1, the hens had little response to NaHCO₃ supplementation and showed a negative trend on eggshell thickness and strength.

6. It is concluded that dietary supplementation with 3 g NaHCO₃ g/kg improves Ca absorption and eggshell quality of laying hens during the peak but not late production period, with the introduction of continuous lighting.

     

Role of the “National Reference Centre for Genetically Modified Organisms (GMO) Detection” in the Official Control of Food and Feed

The National Reference Centre for Genetically Modified Organisms (GMO) detection was established in 2002 within the Istituto Zooprofilattico Sperimentale Lazio e Toscana, with the aim of providing scientific and technical support to the National Health System and to the Ministry of Health within the scope of the regulation of GMO use in food and feed.

The recently adopted EU legislation on GMOs (Regulation CE no. 1829/2003 and no. 1830/2003) introduced more rigorous procedures for the authorisation, labelling and analytical control of food and feed consisting, containing or derived from GMOs. The National Reference Centre, besides its institutional tasks as one of the laboratories of the Italian National Health System, collects and analyses data and results of the national official control of GMOs; carries out scientific research aimed at developing, improving, validating and harmonising detection and quantification methods, in cooperation with other scientific institutions, the Community Reference Laboratory and within the European Network of GMOs laboratories (ENGL); collaborates with the Ministry of Health in the definition of control programmes and promotes educational and training initiatives. Objectives defined for 2004–2006, activities in progress and goals already achieved are presented.

     

Virulence factors and antimicrobial susceptibility of Escherichia coli isolated from calves in Turkey

Escherichia coli isolates from calves were investigated by multiplex PCR assays for the presence of genes encoding K99, F41, F17-related fimbriae, heat-stabile enterotoxin a (STa), intimin (eae) and Shiga toxins (stx1 and stx2). A total of 120 E. coli isolates, 75 isolated from diarrhoeic or septicemic calves and 45 from clinically healthy calves aged between 1 day and 2 months were tested. Each isolate was obtained from different calves in different herds. Among the isolates from diseased animals, 12 (16%) isolates from 1- to 7-day-old diarrhoeic calves were detected as enterotoxigenic E. coli which possessed K99, F41 and STa in combination; F17-related fimbriae genes were detected in 33 (44%) isolates and they were found in combination with K99 + F41 + STa in two isolates. Of 120 isolates, 16 carried eae, eight stx1 and five stx2 genes alone or in combination. None of the eae- or stx-positive strains was identified as O157:H7. However, results indicate that calves may be carrier of Shiga toxin-producing E. coli which have potential as a human pathogen. Antimicrobial susceptibility of 75 isolates from diseased calves was determined by agar disk diffusion method for 14 antimicrobial agents. In 77.3% of the isolates, multiresistance was detected. Higher resistance rates were detected for cephalothin (72%), tetracycline (69.3%), kanamycin (69.3%), ampicillin (65.3%), nalidixic acid (53.3%), trimethoprim-sulphamethoxazole (52%) and enrofloxacin (41.3%), respectively. No resistance was found for ceftiofur and cefoxitin.     

Pharmacokinetics of meloxicam in adult goats: a comparative study of subcutaneous,oral and intravenous administration

AIMS: To determine the plasma disposition of meloxicam in goats following S/C, oral or I/V administration at a single dose of 0.5?mg/kg bodyweight.

METHODS: Five healthy Saanen goats, aged 12–14 months and weighing 35–40?kg, were used for a three phase cross-over design with a 10-day washout period, with meloxicam administered I/V, then orally and S/C. Heparinised blood samples (5?mL) were collected from all animals prior to drug administration (0 hours) and subsequently up to 96 hours. Concentrations of meloxicam in plasma were measured using high performance liquid chromatography. Concentration-time curves were fitted and pharmacokinetic parameters were estimated for each administration group.

RESULTS: Subcutaneous administration of meloxicam exhibited unique plasma distribution characteristics that differed from oral and I/V administration. Mean peak plasma concentrations were greater (1.91 (SD 0.39) vs. 0.71 (SD 0.17) µg/mL) and the time to reach them shorter (3.20 (SD 1.64) vs. 14.33 (SD 2.19) hours) following S/C compared with oral administration (p<0.05). The terminal half-life was longer (15.16 (SD 4.74) vs. 10.69 (SD 1.49) hours) and the MRT was shorter (15.67 (SD 2.37) vs. 24.33 (SD 3.12) hours) following S/C than oral administration (p<0.05), but bioavailability was similar (98.24 (SD 9.62) vs. 96.49 (SD 10.71)%).

CONCLUSION AND CLINICAL RELEVANCE: Subcutaneous administration of meloxicam resulted in long-term presence of drug at high concentration in goat plasma. This unique plasma disposition characteristic may offer an advantage in some clinical cases towards potentially improving the treatment efficacy in goats.     

Computed Tomography of the Normal Bovine Tarsus

The objective of this study was to provide a detailed multiplanar computed tomographic (CT) anatomic reference for the bovine tarsus. The tarsal regions from twelve healthy adult cow cadavers were scanned in both soft and bone windows via a 16‐slice multidetector CT scanner. Tarsi were frozen at ?20^o C and sectioned to 10‐mm‐thick slices in transverse, dorsal and sagittal planes respecting the imaging protocol. The frozen sections were cleaned and then photographed. Anatomic structures were identified, labelled and compared with the corresponding CT images. The sagittal plane was indispensable for evaluation of bone contours, the dorsal plane was valuable in examination of the collateral ligaments, and both were beneficial for assessment of the tarsal joint articulations. CT images allowed excellent delineation between the cortex and medulla of bones, and the trabecular structure was clearly depicted. The tarsal soft tissues showed variable shades of grey, and the synovial fluid was the lowest attenuated structure. This study provided full assessment of the clinically relevant anatomic structures of the bovine tarsal joint. This technique may be of value when results from other diagnostic imaging techniques are indecisive. Images presented in this study should serve as a basic CT reference and assist in the interpretation of various bovine tarsal pathology.     

Tetanus in a Camel (Camelus dromedarius) – A Case Report

Twenty days after an open castration, a 5-year-old dromedary was presented to the Dubai Camel Hospital with severe central nervous symptoms. The dromedary showed the following signs: off feed, stiff gait with extended neck, external swelling of the preputial sheath and groin region, and foamy saliva drooling from the mouth. The dromedary was unable to swallow. Three days after admission, the camel developed lockjaw, and on the fifth day it was unable to stand owing to paralysis of the hindquarters. Because of the severity of the disease and because it did not respond to treatment, the camel was euthanized 26 days after the operation and submitted to the Central Veterinary Research Laboratory for further investigation. Both castration wounds were closed and spermiducts were filled with necrotic masses from which Clostridium tetani was isolated. Two mice, which were injected with the filtrate of the thioglycolate broth, developed typical signs of tetanic spasm of the hind leg. Faecal samples from camel and horse paddocks that were only 50 metres apart were negative for C. tetani. However, C. tetani was isolated from two soil samples of the horse paddock. It is recommended that camels should be vaccinated against tetanus prior to castration.