Banca de QUALIFICAÇÃO: RAFAEL ALEXANDRE QUEIROZ

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : RAFAEL ALEXANDRE QUEIROZ
DATE: 07/08/2024
TIME: 14:00
LOCAL: https://meet.google.com/icr-msqy-ozi
TITLE:

Immediate Post-Mortem Assessment of the Carpal-Radial Extensor Reflex in Sheep Following Radial Nerve Section

KEY WORDS:

Neurology; small ruminants; spinal reflex; neurectomy; muscles.

PAGES: 21
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUBÁREA: Clínica e Cirurgia Animal
SUMMARY:

The breeding of sheep has significantly expanded, not only for production purposes but also as pets in both urban and rural areas. This increase in the number of small ruminants kept as pets presents new challenges for veterinary clinics, particularly in managing unconventional animals. Considering the importance of proper neurological assessment in sheep and the need for precise and reliable information at each stage of this examination, our research aims to identify the reliability of the carpal-radius extensor reflex for diagnosing spinal alterations in this species. We selected 30 sheep from the municipal abattoir in Rajada – PE (a district of Petrolina – PE), ranging in age from five months and exhibiting standard body conformation and muscle development for the species. These sheep had no abnormalities in their gait. We performed the carpal-radius extensor reflex test on both thoracic limbs of each animal (totaling 60 limbs) using a neurological percussion hammer. Initially, the reflexes were assessed before slaughter, while the animals were still in the pen, with the evaluated limb positioned upward while the animal lay in lateral recumbency. Subsequently, the animals were moved to the slaughter line, where the reflex tests were repeated after stunning (using a captive-bolt pneumatic pistol), bleeding, and confirmation of cardiac arrest. Finally, neurotomy of the radial nerves was performed, and the reflexes were reevaluated. We documented the results after three consecutive assessments for each limb. The responses were evaluated quantitatively and qualitatively, classified as follows: 0 (absence of response), 1 (diminished response), 2 (normal response), and 3 (increased response). Reflex level data showed an abnormal distribution and were analyzed in pairs using the non-parametric Wilcoxon test. Similar to findings in dogs and cats, there was muscular response (observed in 96.66% of sheep) even after cardiac arrest and complete disappearance of the flexor reflex (withdrawal reflex). Additionally, this response persisted even after radial nerve section. These results indicate that in these two species, the carpal-radius extensor reflex is not related to spinal myotatic reflexes involving lower motor neurons (LMNs) and the arc reflex. Instead, it characterizes an idiomuscular response, similar to what occurs in humans, dogs, and cats. Consequently, the carpal-radius extensor reflex is not reliable for assessing spinal cord lesions in sheeps.

COMMITTEE MEMBERS:
Presidente - JOAQUIM EVENCIO NETO
Interno - EDUARDO ALBERTO TUDURY
Interna - GRAZIELLE ANAHY DE SOUSA ALEIXO CAVALCANTI