Origin and distribution pattern of pelvic limb nerves of a Bengal tiger (Panthera tigris tigris).

The Bengal tiger (Panthera tigris tigris) is a species belonging to the Felidae family. In Argentina, tigers are currently only found in captivity. The longevity of individual animals in human-controlled environments depends on proper management and practices that prioritize animal welfare. Regular veterinary care is essential to maintain optimal health conditions. Professionals must have a comprehensive understanding of the anatomy and physiology of tigers to effectively perform medical procedures and administer treatments. The study described in the text focuses on the trajectory and distribution of nerves in the pelvic limb of a Bengal tiger specimen, providing detailed dissection findings. The results revealed that the lumbosacral plexus is formed from the ventral rami of the LIV, LV, LVI, LVII, SI, SII and SIII nerves. Among the observations to highlight is the great development of the nerves N. cutaneus femoris lateralis and N. cutaneus femoris caudalis some differences were observed in the distribution of the N. femoralis and N. obturatorius; the N. ischiadicus, together with its division into the fibularis communis and tibialis nerves, showed the same configuration observed in other cats. Finally, it was observed that the nerves N. gluteus cranialis and N. gluteus caudalis also originated from the truncus lumbosacralis. The similarities and differences with studies carried out on other cats are relevant and provide anatomical data for medical procedures in the Bengal tiger.

Impact of very old age on hypothalamic dopaminergic neurons in the female rat: a morphometric study.

Dopaminergic neurons of the A(12) (tuberoinfundibular dopaminergic system) and A(14) (periventricular dopaminergic system) hypothalamic areas exert a tonic inhibitory control of prolactin secretion. Tuberoinfundibular dopaminergic system neuron function is known to decline during aging in rats, but little is known about the impact of extreme age on neuron number and morphology in the two systems. We morphometrically assessed the neurons of the tuberoinfundibular dopaminergic system and the periventricular dopaminergic system in female rats 6 (young, Y), 24 (old, O), and 30-32 (senescent, S) months old. Serial coronal sections of fixed hypothalami were immunohistochemically labeled for tyrosine hydroxylase, and immunoreactive perikarya from the A(12) and A(14) areas were quantitatively characterized and compared among the three age groups. Radioimmunoassay was used to measure serum prolactin. The number of A(12) tyrosine hydroxylase-immunoreactive perikarya showed a steady decline with age, whereas the number of A(14) tyrosine hydroxylase-immunoreactive perikarya remained stable from young to old age but showed a sharp drop in the senescent rats. In the old rats, tyrosine hydroxylase-immunoreactive neuronal area (A(12) = 135.37 and A(14) = 158.79 microm(2)) was significantly higher than that of young (A(12) = 72.56 and A(14) = 99.7 microm(2)) and senescent animals (A(12) = 95.5 and A(14) = 106.5 microm(2)). Densitometric assessment of median eminence tyrosine hydroxylase immunoreactivity revealed a steady age-related reduction of tyrosine hydroxylase content in the median eminence. Serum prolactin levels increased steadily with age. We conclude that, in the female rat, aging brings about a progressive loss of both tuberoinfundibular dopaminergic system and periventricular dopaminergic system neurons, which becomes more conspicuous at extreme ages.