Review/Oorsig Volume 22, Issue 05 - Page 8

Oorsig/Review to the abomasal fluid and if only abomasal fluid is set up on culture, these cases can be missed. In light of this information abomasal fluid and placental cotyledon should routinely be set up on culture. Some bacterial / fungal infections are capable of passing through the placenta without initiating a placentitis. For this reason fresh lung and liver should be collected and frozen away. Should abomasal fluid and placenta return negative results but histopathology suggests sepsis, these organs can be set up on culture. Mineral analysis This can be reliably performed on formalin fixed tissues. The minerals which are validated on formalin fixed material include selenium, copper, zinc, iron, cobalt and manganese. Preservation of liver tissue in formalin for up to one month had no significant effect on these trace element levels, except for manganese. The drop-in manganese levels were associated with leaching. Therefore, performing mineral analysis on formalin fixed tissue within one to 2 weeks of collection provides reliable diagnostic information as regards deficiency or toxicity of a particular mineral. The differences in mineral concentration between fresh liver and liver stored in formalin (1 – 2 weeks) are statistically insignificant. Diagnostic Sample Synopsis • • • • • Microbiology (bacterial, fungal) – Abomasal fluid and Placenta (freeze lung, liver). Histopathology – brain, thyroid, heart, lung, thymus, liver, spleen, kidney, lymphnode, adrenal, intestine, skin (eyelid). Immunohistochemistry – various infectious agents (formalin fixed tissue sections) Molecular Biology (polymerize chain reaction) – specific viral etiologies (spleen, lymphnode, brain) and bovine fetus abomasal fluid (Tritrichomonas foetus and Campylobacter fetus). Mineral analysis (Se, Cu, Fe, Mn, Zn, Cr). Further reading. 1. 2. 3. 4. Maxie M G. 2016. Pathology of Domestic Animals 6th edition. Elsevier, St. Louis. Njaa B L. 2012. Kirkbride’s Diagnosis of abortion and neonatal loss in animals. 4th edition. Wiley-Blackwell, Ames. Smith C. 2002. The effect of preserving liver tissue in formalin on the concentration of trace minerals in the liver. Masters thesis. University of Pretoria. Steffan D. 2003. Investigating Congenital Diseases in Calves. The Nebraska Genetic Disease Diagnosis and Consulting Program. C.L.Davis Foundation Symposium on Reproductive Diseases, San Diego, USA. THE VETERINARY LABORATORY DIAGNOSTIC TEAM AT YOUR SERVICE Dr Maryke Henton - BVSc, M.Med.Vet (Bacteriology) 2 Dr Rick Last - BVSc, M.Med.Vet (Pathology) 1 Dr Samantha Tompkins - BVSc, M.Med.Vet (Pathology) 2 Dr James Hill - BVSc, M.Med.Vet (Clin Pathology) 1 Dr Sandy May - BVSc, M.Med.Vet (Clin Pathology) 3 Dr Johan Vorster - BVSc, M.Med.Vet (Pathology) 1 Vetdiagnostix KZN 1 LABORATORY 257 Boshoff Street Pietermaritzburg Vetdiagnostix Gauteng 2 LABORATORY 96 Poplar Road Blue Hills, Midrand Vetdiagnostix Cape Town 3 LABORATORY 01 Kontiki Way Glen Ive, Bellville Tel: (033) 342 5014/5 (033) 342 6144 082 558 4016 074 137 9132 (Main Lab) 074 162 0559 (Main Lab) 071 563 6947 (Duty Cell) Tel: (021) 910 2243 (021) 910 1413 078 436 2560 (Duty Cell) 8