Welfare and pregnancy rate of ewes undergoing transcervical artificial insemination with ketamine subarachnoid anesthesia.

This study aimed to evaluate the impact of subarachnoid anesthesia with ketamine during transcervical artificial insemination (TCAI) on the welfare of ewes and on subsequent pregnancy rates. Ninety Suffolk adult ewes were randomized into three treatment groups: control group (CG), which underwent the TCAI procedure as established by cervical traction (CG; n = 30) and two groups that received subarachnoid anesthesia with ketamine at a dose of either 0.75 mg/kg (KE0.75; n = 30) or 1.5 mg/kg (KE1.5; n = 30) 5 min before the cervical traction procedure. Intrauterine insemination was performed using frozen semen from three males previously analyzed and approved for fertility. The use of subarachnoid anesthesia decreased ewes' vocalizations (P = 0.0001) and abdominal contraction (P = 0.0150) during cervical manipulations. The CG had more groans and vocalizations at the moment of cervix clamping and applicator passage through the cervix (P = 0.001). The cervix traction was facilitated by anesthesia. For the control group, most of the cervical traction was done just up to the middle of the vagina (P = 0.0021). Pregnancy rates increased significantly with anesthesia (P = 0.04) as shown by the rates of 40.0%, 56.7%, and 66.7% for CG, KE1.5, and KE0.75, respectively. The CG showed behaviors associated with absolute immobility, which is suggestive of distress. In brief, the use of ketamine in subarachnoid anesthesia for transcervical artificial insemination in ewes facilitated cervical traction, increased the pregnancy rate, and improved animal welfare.

Effects of caudal epidural ketamine and/or lidocaine on heifers during reproductive procedures: a preliminary study.

Six 20-24-month-old heifers received ketamine (KE), 2% lidocaine (Li), or ketamine and 2% lidocaine (KELI) into the first intercoccygeal (Co(1)-Co(2)) epidural space while standing. Heart rate, arterial blood pressure (systolic, diastolic, and mean), respiratory rate, rectal temperature, analgesia, sedation, and ataxia were determined before treatment and at predetermined intervals. Subjective scoring was used to assess pain and discomfort in reproductive manipulations. The duration of analgesia was 35+/-14 min for Li, 48+/-11 min for KE, and 35+/-7 min for KELI (P>0.05). Motor block determined by KE, Li, or KELI treatments was restricted to tail, external genital organs (vulva and vagina), anus, and rectum, with little interference in the cervix or uterus. It was concluded that epidural ketamine, 2% lidocaine, or their combination produced satisfactory analgesia without discomfort or ataxia and facilitated reproductive manipulations.