The cleaned skulls of 39 wild and 30 domestic pigs from southern Illinois (USA) were assessed for dental anomalies including polydonty, oligodonty, misalignment, and rotation. Dental anomalies occurred in 16 wild and 15 domestic pigs. Oligodonty (either bilateral or unilateral) was the most common anomaly, occurring in 9 wild (23.1% of the sample) and 15 (50%) domestic pigs. In 22 of the 24 individuals exhibiting oligodonty, this anomaly involved the lower first premolar (P1. Given the placement of P1, oligodonty may reflect a trend toward reduction of the dental arcade from the primitive eutherian number. Domesticated species are reported to have more anomalies than wild counterparts because of inbreeding. We found no difference in the number of dental anomalies between domestic and wild pigs.
The anatomical structure of the middle cerebral artery in domestic pig (Sus scrofa f. domestica) was defined using 88 cerebral hemispheres. It was observed that the artery ramified into ten permanent branches. Two rhinal arteries supplied the area of cerebrum on the border between the old and the new cerebral cortex. The other eight branches bifurcated into three branches going into the frontal area, two branches - the parietal area and three temporal branches which supplied the new cerebral cortex exclusively. In domesic pig, most frequently, 38.7 %, the rostral cerebral artery gave rise to two and, in 59.1%, three independent branches. In one hemisphere (1.1%) the rostral cerebral artery gave rise to one main trunk of the middle cerebral artery. Similarly in one individual there were observed six independent branches of that artery.
Localisation and morphology of myocardial bridges in the heart of domestic pig remain an open issue. Since these structures significantly influence haemodynamics in the coronary arteries, their occurance may lead to numerous pathologies. In the examined group of 150 domestic pig’s hearts, myocardial bridges were diagnosed in 47.3% of the material, mostly in males. In majority of cases the bridges were present above the posterior interventricular branch of the right coronary artery, less often above the anterior interventricular branch of the left coronary artery, and seldom above other blood vessels. The presence of myocardial bridges usually referred to the medial and initial segments of the arteries examined.
A study was carried out of 30, 160 ejaculate samples collected from 81 boars of the wbp (Polish Large White) breed and 182 boars of the pbz (Polish Landrace) breed. The ejaculate was collected manually with the sampling frequency of 4 - 5 days. An assessment of the ejaculate has been done with regard to the following physical properties: ejaculate volume, sperm cells concentration, percentage of sperm cells exhibiting proper motility, total number of sperm cells in the ejaculate and number of insemination doses obtained from one ejaculate. The collected data have been analyzed according to the season criterion with indication of the ejaculate collected in the individual months. It has been revealed that the most suitable ejaculate was collected from the domestic pig boars in November and December whereas in March, April and May the parameters lowered. The ejaculate collected in the springtime is characterized by a lower volume and a lower number of the motile sperm cells than in the other seasons. From the ejaculate collected in the autumn and winter period more insemination doses can be prepared than from those collected in spring and summer. No difference has been found between the boars of the wbp and pbz breeds with regard to their susceptibility to the seasonal factors’ influence.
The experiment was carried out on 29 hybrids (21 barrows and 8 gilts) of Duroc sows with wild boar (Sus scrofa ferus L.). All the animals were fed (ad libitum with composed fix) from weaning up to the age of approx. 8 months. The samples of Longissimus lumborum for histopathological study were collected 45 min after slaughter and were frozen with liquid nitrogen. Microscopic preparations were stained according to the Van Gieson method. The following types of histopathological changes were accounted for: changes in fibre size (fibre atrophy, hypertrophy – giant fibres), changes in fibre shape (triangular, trapezoid and elongated fibres), degenerative changes of fibres (necrosis plus phagocytosis, fibre splitting) and connective tissue hypertrophy. Most often appearing pathological change in the muscle was fiber atrophy. It was observed in all animals. The other changes appeared with greater frequency in gilts. Percentage of particular pathological changes was low, 95.84% of normal fibers were found.