A novel method for transuterine identification of piglets

Abstract

SummaryImplantable microchips provide a secure, permanent and unique identification of individual animals. When performing fetal intervention studies in experimental animal models easy and secure identification of fetuses is desirable, as having test and control groups within the same uterus reduces the total number of animals used in a study. The aims of this study were: (1) to establish a protocol to identify porcine fetuses in utero by microchip implantation and (2) to assess postnatally whether clinical or pathological reactions to the implant occurred. Two Danish Landrace/Danish Large White crossbred sows at day 100 of gestation were used. The sows were sedated with azaperone and induced with propofol intravenously. Anaesthesia was maintained with isoflurane and oxygen. Antibiotics were administered intramuscularly (i.m.) at induction and analgesia was given pre-, intra-and postoperatively. A laparotomy was performed and the uterus exteriorized. The rump of the first fetus was recognized through the uterine wall and the thigh muscle of the fetus was fixed between the thumb and the forefinger. The microchip was then implanted into the fetus at an angle of 458 i.m. in the lateral hindleg using an insertion device with a 12G needle. The same procedure was done in every fetus. The uterus was returned to the abdomen and the abdominal wall closed. The sows gave birth to 24 liveborn piglets and one stillborn. None of the liveborn piglets were limping at the time of birth and no visible cutaneous or palpable reactions on the hindlegs were observed. Following euthanasia, the microchip was easily localized and no macroscopic reactions at the implantation site were seen. None of the piglets had more than one microchip implanted. Histology showed a chronic mild foreign body granulomatous inflammatory response with peripheral eosinophils surrounding the microchip. No inflammation was evident in the adjacent muscles. It is concluded that transuterine identification of piglets two weeks before delivery is feasible using a microchip implant as an effective, easy and reliable method for identification of individuals after birth.

Single port laparoscopic long-term tube gastrostomy in Göttingen minipigs

“…The chronic mild inflammatory reaction found in the gastric wall was comparable to similar foreign body reactions described in pigs. 19…”

“…On the day of surgery, the pigs were sedated with 0.06 mL/kg BW of ‘swine mixture’ (125 mg tiletamine [0.75 mg/kg] and 125 mg zolazepam [0.75 mg/kg] [Zoletil 50; ChemVet, Silkeborg, Denmark] + 125 mg xylazine [0.75 mg/kg] [Narcoxyl vet 20 mg/mL; Intervet, Ballerup, Denmark] + 125 mg ketamine [0.75 mg/kg] [Ketaminol vet 100 mg/mL; Intervet] + 25 mg butorphanol [0.15 mg/kg] [Torbugesic vet 10 mg/mL; Scanvet, Fredensborg, Denmark]), as previously described. 19 Anesthesia was induced with propofol (1–2 mg/kg BW intravenously) (Rapinovet vet 10 mg/mL; Schering-Plough Animal Health, Ballerup, Denmark). After intubation and placement of an esophageal tube, the pigs were kept on a balanced total intravenous anesthesia (TIVA) with propofol (5–15 mg/kg BW/h) and fentanyl (10–30 µg/kg BW/h) (Haldid; Janssen-Cilag A/S, Birkerød, Denmark).…”