Necropsy: Barbiturate Residue Rendering Guidelines

Background: Federal regulations and vendor policies exist prohibiting the use of barbiturates in euthanasia of animals disposed of by rendering or landfill.
Species affected and disposal options: The following species can be rendered, if not euthanized with barbiturates or diagnosed with a select agent: bovines <30 months of age (including fetuses), bovines > 30 months of age with brain and spinal cord removed, bovines > 30 months of age with a negative BSE test, small ruminants with a negative scrapie test, poultry, pigs, camelids, lagomorphs, and fish. In addition to animals euthanized with barbiturates or animals diagnosed with a select agent, the following species cannot be disposed of by rendering: cervids, horses, large wildlife and zoo animals. Incineration is a disposal option for domestic dogs and cats, mustelids, pocket pets, and small wildlife and zoo animals.
WVDL Zero Tolerance Barbiturate Policy

File: CL-Res-105-Necropsy-Barbiturate-Residue-Rendering-Guidelines.pdf

Large Animal Humane Euthanasia Guidelines

(Provided by UW School of Veterinary Medicine)
Excerpts from AVMA Guidelines for the Euthanasia of Animals (2020):
POTASSIUM CHLORIDE AND MAGNESIUM SALTS, p. 36: ‘Personnel performing this technique must
be trained and knowledgeable in anesthetic techniques, and be competent in assessing the level of
unconsciousness that is required for administration of potassium chloride and magnesium salt
solutions IV. Administration of potassium chloride or magnesium salt solutions IV requires animals
to be in a surgical plane of anesthesia characterized by loss of consciousness, loss of reflex muscle
response, and loss of response to noxious stimuli.’
RUMINANTS, p. 67-68: ‘While not acceptable as a sole method of euthanasia, rapid IV injection of
potassium chloride may assist in ensuring death after cattle have been rendered unconscious by
penetrating captive bolt, gunshot, or administration of general anesthetics (a-2 adrenergic agents
such as xylazine alone are insufficient; see comments under Unacceptable methods).’
EQUINE, p. 78: ‘Recently, rendering plants and landfills have refused equine carcasses euthanized
with pentobarbital. For this reason, adjunctive methods should be considered. Anesthetizing the
equid with xylazine – ketamine should be followed by one of the following: (1) saturated solution of
potassium chloride injected IV or intracardially; (2) saturated solution of magnesium sulfate
injected IV; or (3) 60 mL of 2% lidocaine injected intrathecally. Each of these performed in an equid
in a deep surgical plane of anesthesia is an acceptable method to invoke cardiac arrest and death.’

File: CL-Res-104-Large-Animal-Humane-Euthanasia-Guidelines.pdf

Milk Sample Collection Guidelines

Milk samples may be collected individually from each affected quarter (quarter milk samples) or combined from multiple quarters of a cow into one sample tube (composite milk samples). Composite milk samples are not recommended however, as cultures usually reveal growth of numerous different bacterial species, making it difficult, if not impossible, to determine which pathogens are causing mastitis and which are environmental contaminants. Isolation of contagious organisms, such as Staphylococcus aureus, Streptococcus agalactiae, or Mycoplasma sp., are indicators of true infections of the udder. Environmental organisms, such as Streptococcus spp., coliforms, Staphylococcus spp., (coagulase negative Staph.), Pseudomonas sp., Corynebacterium sp., yeast, and fungi, may be contaminants or true infections. Unless only screening for contagious pathogens, composite milk samples should be avoided.
Milk samples may become contaminated with bacteria from the hands of the sample collector, the environment, and the teat, skin or teat canal of the cow. It is important that proper sample collection techniques are used in order to avoid contamination of the milk sample.

File: CL-Res-59-milk-sample-collection-1.pdf

Necropsy: Respiratory Disease Sampling Guidelines

The ideal samples for investigation of respiratory diseases are those that are collected within 4-8
hours of death, however, any sample is better than none, and the lab does not charge based on
the number of samples submitted. Both fresh and formalin fixed tissues from 2-4 different sections
of lung including the junction between normal and diseased tissue.

File: CL-Res-37-Necropsy-Respiratory-Disease-Sampling-Guidelines.pdf