Slaughter of pregnant Tanzania shorthorn Zebu cattle at Morogoro abattoir: Prevalence, fetal wastage, and placentome morphology

Abstract

Slaughtering pregnant cattle for meat is unethical, impends food security, and brings animal cruelty. A six-month study spinning from June and December 2020 was carried out to determine the number of Tanzania shorthorn zebu (TSHZ) slaughtered cattle, level of fetal wastage, number, size, and morphology of placentomes and their relationship with fetal age, sex, weight, and location in uteri. Results showed that 15,239 cattle were slaughtered, of which 99% (n=15,087) were TSHZ aged above three years. 61.38% (n= 9,353) of slaughtered cattle were female cattle, of which 2,599 (27.79%) were pregnant at varied gestation periods, and only 5,886 (38.63%) were males. Recovered fetuses were 1,450 (55.79%) males and 1,149 (44.21%) females, with a total of 1,081 (41.59%), 919 (35.36%), and 599 (23.05%) recovered in the first, second and third trimester, respectively. Fetal ages varied from 2.2 to 8.9 months, with body length (crown-crump) ranging from 13.7 to 83.1 cm. Fetus weight ranged from 1.1 kg to 23.2 kg. A total of 1545 (59.45%) pregnancies were localized in the right uterine horn, whereas 1054 (40.55%) were in the left uterine horn. The number of placentomes was significantly larger (P < 0.05) in gravid horns ranging from 71 to 115, than in non-gravid horns (5-28). Placentomes in gravid horn were greatly vascularized, large in size, convex in shape, and measured 7 cm in length and 2 cm in width. In non-gravid horns, placentomes were pale, small, and flat and measured 4 cm in length and 1 cm in width. At the microscopic level, the fetal cotyledons comprised a chorionic plate with a smooth external surface of cuboidal epithelium. From the chorionic plate's internal surface, numerous primary villi sprout inside in a pinnate fashion, producing secondary and tertiary villi. A significant fetal loss was resulting from the slaughter of pregnant animals warrants stepping up routine veterinary ante-mortem inspection of traded animals to salvage the high level of fetal wastage.