Unilateral flank ovariohysterectomy in guinea pigs (Cavia porcellus).

AIMS: To describe a simple, minimally invasive method of ovariohysterectomy via a unilateral flank approach in guinea pigs, for use in routine desexing of healthy female guinea pigs or treatment of ovarian cysts. METHODS: The subjects of this retrospective study were 41 client-owned guinea pigs submitted for routine desexing or treatment of ovarian cysts. They included 16 healthy female guinea pigs aged 8-12 months (Group 1), and 15 females aged from 9 months to 3 years (Group 2), and 10 females aged from 3 to 7 years (Group 3) with different-sized ovarian cysts. Prior to surgery, the animals received clinical examination, blood testing (complete blood count and serum biochemistry profile) and examination of the abdomen using ultrasonography, to assess the condition of the reproductive tract and ensure the guinea pigs were fit for surgery. Ovariohysterectomy was performed via a unilateral flank incision made close to the erector spinae muscle starting approximately 1 cm caudal to the last rib. Both ovaries, uterine horns, and the uterine cervix were localised, ligated, and dissected through this unilateral retroperitoneal incision. RESULTS: Ovariohysterectomy was successfully completed via a single flank incision in 38/41 (93%) guinea pigs. Three guinea pigs with ovarian cysts from Group 3, which were >6 years old died during surgery due to circulatory and respiratory failure under anaesthesia. In the remaining 38 cases, surgery proceeded without complications. A further two guinea pigs from Group 3 were reluctant to move or eat for the first 3 days after surgery but recovered after provision of supportive care. All 38 animals fully recovered and wound healing was normal. CONCLUSIONS: This is the first report of ovariohysterectomy via a unilateral flank incision in guinea pigs. This approach is a simple, minimally invasive and safe alternative to the midline or bilateral flank approaches currently used for surgery of the reproductive tract in guinea pigs.

Relevance of Molecular Changes in the ND4 Gene in German Shepherd Dog Tumours.

The aim of the study was to identify polymorphisms and mutations in the mitochondrial ND4 gene and to analyse the associations between the occurrence of molecular changes in mtDNA and phenotypic traits in tumours in German Shepherd dogs. Fifty samples obtained from blood and tumour tissues of German Shepherd dogs with diagnosed tumours were analysed. DNA extraction, amplification, and sequencing of the mtDNA ND4 gene, and bioinformatics, statistical, and in silico protein coding SNP analyses were performed. ND4 mutations and/or polymorphisms were noted in eleven nucleotide positions in nearly half of the examined dogs. All the changes were substitution mutations. A majority of the changes identified were homoplasmic. In one dog with osteosarcoma, blood heteroplasmy was detected. In two positions of the ND4 gene, presence of non-synonymous mutations leading to amino acid changes in the ND4 protein was reported. Analyses carried out to determine the deleterious effect of mutations indicated an almost 97 and 62% probability that a single amino acid substitution (p.G239V and p.I401T, respectively) in the protein has a negative impact on its function. The results of statistical analyses indicate a significant association between the occurrence of mutations in three loci of the ND4 gene and the location of tumours. The mutations identified may be a result of cell adaptation to the changes in the environment occurring during carcinogenesis. The high frequency of mutations in the tumours may indicate genetic instability of mtDNA, which may also play a role in carcinogenesis.

Evaluation of medetomidine-midazolam-atropine (MeMiA) anesthesia maintained with propofol infusion in New Zealand White rabbits.

An anesthetic combination of medetomidine-midazolam-atropine and propofol was investigated in twenty New Zealand White rabbits. Each rabbit received combined medetomidine at a dosage of 0.2 mg/kg (b.w.), midazolam (0.5 mg/kg b.w.) and atropine (0.5 mg/kg b.w.) intramuscularly for induction of anesthesia. Propofol was administered intravenously - given to effect, and after that by an infusion pump to maintain anesthesia. The influence of the anesthetic combination on the cardiopulmonary system was evaluated by monitoring respiratory and heart rates, blood pressure, and arterial blood gas tensions. The results obtained showed that propofol infusion at a rate of 0.5 mg/kg b.w./min maintained general anesthesia effectively with few side effects on the cardiopulmonary system during 30 minutes. However, slight hypotension, hypercapnia, and respiratory acidosis were associated with infusion of this anesthetic. The recovery of the rabbits from the anesthesia was smooth. Two rabbits died 20 to 24 hours after anesthesia. In conclusion, an anesthetic combination with medetomidine-midazolam-atropine and propofol at the investigated doses was shown to be a safe method to induce and maintain general anesthesia enabling short-term surgical procedures in healthy animals.