Growth and Behavior of Congenitally Anophthalmic Lee-Sung Pigs.

Circadian rhythm is usually regulated by the environmental light-dark cycle. Congenitally anophthalmic miniature pigs provide a valuable model for the study of factors affecting circadian rhythms in the absence of visual exposure to the light-dark cycle. This study investigated the growth and daily behavior patterns of Lee-Sung pigs with congenital anophthalmia. Growth in 5 Lee-Sung pigs (LSP) with congenital anophthalmia (LSP-A) and 10 normally developed pigs (LSP-N) was assessed when they were 1 through 6 mo old. Behavioral studies using digital video recording were completed in 6 sexually mature LSP (3 LSP-A and 3 LSP-N). MRI showed that LSP-A lose their vision because of a lack of retinal input and optic chiasm development. LSP-N and LSP-A did not differ in body weight or size at 2, 4, and 6 mo of age. Behavior and activity pattern studies showed that both LSP-A and LSP-N were active mainly during daylight, but LSP-A spent significantly more time exploring their environment during the day (28%) and night (10%) than did LSP-N. This study revealed that growth performance was similar between LSP-A and normal pigs, but their behavior and activity patterns differed. LSP-A showed circadian rhythm abnormalities similar to those in blind humans. This study provides basic data on LSP-A as a model for studying compensatory cross-modal brain plasticity and hormone regulation in the absence of retinal input is deficient and for understanding the role of circadian rhythm regulation.

The incidence of congenital malformations and variations in Göttingen minipigs.

Knowledge of the incidence of spontaneous congenital abnormalities is critical for the accurate interpretation of findings in teratogenicity studies in any species. In this paper, results of the examination of 1739 neonatal Göttingen Minipigs are presented. Over the 2-year period under consideration, the incidence of external and visceral malformations was less than 0.2 and 0.1%, respectively. The most common external malformations were syndactyly, limb hyperflexion, domed head and scoliosis. The most common internal malformations were undescended testes, ventricular septal defect, diaphragmatic hernia and atrial septal defects. Pentadactyly and variation in the aortic arch's bifurcation (absent truncus bicaroticus) were the most common variations. These data will help support the use of the Göttingen Minipig as a non-rodent species in embryofetal development studies where concerns persist about the availability of background data.