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Clostridium perfringens enterotoxin
Detection of ovarian activity in the bitch
How big is a blood cell
Streptococcus suis death
Clin Path Club Report
Tail End: $3 million Dollar Dog

Clostridium perfringens Enterotoxin
New test available
Clinical Signs.
Clostridium perfringens infection can cause acute or chronic diarrhoea. The diarrhoea may be watery or muco-haemorrhagic with sloughing of the mucosa in severe cases. Tenesmus may be present and severe anal inflammation can also occur. Signs may be intermittent and cyclic in chronically infected animals. Cases typically reoccur after anti-microbial therapy is discontinued.
Clostridium perfringens is a normal inhabitant of the bowel in the vegetative state. Isolation by culture is not definitive of pathogenicity. The organism may be found in healthy animals, it is when some strains undergo sporulation that enterotoxin is released. Antibiotic administration, an alkaline environment, viral infections, dietary alterations and immunosuppression can trigger this. Infection is usually sporadic although outbreaks in grouped animals can occur.

Diagnosis. 
Recovery of the organism in faeces is not diagnostic. Faecal spore counts following heat inactivation of vegetative organisms is unreliable. Similarly demonstration of spores in Gram stained smears of faeces is also unreliable. This is because some strains are non-enterotoxigenic. The best method of diagnosis is specific enterotoxin analysis, which can be performed on faeces from affected, and carrier animals. Only 1 gram of faeces is required. Since its introduction this test has proved popular with gastroenterologists. Results should be available within seven days.
Treatment & Control. This condition often responds poorly to metronidazole. Better results have been obtained using macrolides, penicillins or Synulox. High fibre diets greatly reduce the proliferation of clostridia in the bowel and should be incorporated into a treatment regime, as antibiotic administration can be cause as well as cure.
Test Name =  Clostridial Toxin: Code = CT:  Sample = 1g Faeces: Cost = £15.00
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Detection of Ovarian Activity in the Bitch
Increased sensitivity with gonadotrophin stimulation
It can be difficult to recognise bitches, which have been ovariectomised (neutered). Similarly, ovariectomised bitches may show evidence of oestrus or attraction to males due to the presence of residual ovarian tissue. The current test used to detect ovarian activity has relied upon the detection of an increase in oestradiol following injection of gonadotrophin release hormone (GnRH) (buserelin). The results of this test can be a little unpredictable, possibly due to its dependency on the release of endogenous pituitary gonadotrophins. 
Following the recent work of Jeffcoate et al, an alternative test is now available which is claimed to be more dependable. The authors compared the use of both pregnant mare serum gonadotrophin (PMSG) and equine chorionic gonadotrophin (eCG) as a direct ovarian stimulant.

In ovariectomised bitches serum oestradiol was determined before and 90 minutes after the administration of either PMSG (200-300 IU) or eCG 100-150 IU). In these cases, serum oestradiol was not detectable in either pre or post stimulation samples. In bitches with residual or intact ovaries, there was a marked increase in the post stimulation serum oestradiol level. The pre serum oestradiol levels varied depending upon what stage of the oestrus cycle the bitch was at the time of sampling. 

The author suggests that ovariectomised bitches which show evidence of oestrus should be stimulated but the lab should be requested to test the pre stimulation sample first. This could save the client unnecessary expense. A detectable serum oestradiol level would indicate ovarian activity. If the pre stimulation result is low, the post stimulation sample should be tested.

The authors found no difference in using either PMSG or eCG, price and availability are similar. Following reconstitution unused material should be aliquoted into individual syringes and deep frozen for future use.

JEFFCOATE, I.A., McBRIDE, M., HARVEY, M.J., AUGHEY, E. (2000) Measurement of plasma oestradiol after an injection of a gonadotrophin as a test for neutered bitches. Veterinary Record 146, 599-602
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How big is a red blood cell?
Does size matter?
The size, shape, and number of erythrocytes differ dramatically in different vertebrates. 
The RBCs of most vertebrates are generally nucleated, but mammalian RBCs are enucleate. Some fish and amphibians also have enucleate RBCs. 

The salamander Amphiuma has the largest RBC known: 65 x 30 x 13.5 microns. Avian RBCs are oval shaped, nucleated, and larger than mammalian RBCs (generally 10 to 15 x 5 to 8 microns.). The ostrich has the largest avian RBCs: 16 x 10 microns. Mammalian red blood corpuscles (they are enucleate, hence are not cells) are generally biconcave disks. The camel and llama have elliptical, rather than oval, RBCs, and mouse deer have small, spherical RBCs.

Lower vertebrates tend to have fewer, larger RBCs than higher vertebrates; they have a lower haematocrit (percent packed cell volume) and haemoglobin content, lower RBC counts, larger mean cell volume and mean cell haemoglobin content, but similar mean cell haemoglobin concentration in comparison with birds and mammals.
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Strep suis kills farm worker
First UK case
A West Yorkshire man became the first person to die from Streptococcus suis in the UK. The man, who had recently started work on a pig farm, died within hours of falling ill. Initially the man was thought to have died from streptococcal meningitis.

Streptococcus suis is carried by pigs and whilst it may present a risk to farmers and farm workers, in this case the dead man was thought to have succumbed to infection because he was immunologically compromised following the removal of his spleen after a recent car accident.
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CLIN PATH CLUB REPORT
Dermatophytes a diagnostic dilemma. 
The May meeting was addressed by Alan Leyland, a general practitioner from the Wirral and former lecturer in pathology at the Liverpool Vet School. Alan’s talk took the format of a case presentation of a dog with an apparent dermatophyte infection that subsequently proved to be a symptom of an underlying thyroid disorder. 

Tom Williams of NWL presented a comparison of dermatophyte test media as used in many practice labs. The results demonstrated that false positives could occur due to the presence of normal skin bacteria! 

The discussion raised many aspects of diagnosing dermatophyte infections. Not only the problems of false positives from in house cultures but the pitfalls of using diagnostic aids such as the Woods lamp. Few present realised that the UV tube in such lamps has a very limited shelf life. The wavelength of the UV changes significantly with age. A quick poll indicated that most had no idea of the age of their lamps only that they were “old”.
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Tail End
Veterinary School Receives  $3 Million to Clone  Pet Dog!
An anonymous couple has given the Texas A&M School of Veterinary Medicine $3 million to try to clone the couple's dog, Missy, a Border Collie/Husky mix.

Dr. Mark Westhusin, Professor of Veterinary Physiology at Texas A&M said the so-called "Missyplicity Project" is serious science. "There are a number of objectives and one of them is to develop technology for cloning dogs", Dr. Westhusin said. The research could lead to developing canine contraceptive and infertility treatments and it could also lead to a more reliable supply of dogs to guide the blind and assist in search and rescue missions.
The research could last for years and the initial grant could be increased to as much as $5 million.

Clone pioneers are turning down such offers in the UK. When Dr Griffin at the Roslin Institute, the home of the worlds first animal clone "Dolly" the sheep was asked would they be offering a similar service, he replied "An individual is a lot more than its genes. The idea that you can recreate your pet is false." A clone would have the same genes but a different womb, environment and life history. The result would be a different identity. 
More information at www.missyplicity.com
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