Study on the bone mineral density of broiler suffering femoral joint degenerative lesions

An experiment was carried out with male and females broilers of two different commercial breeds to evaluate bone mineral density of the right femur head. A number of 600 one-day-old broilers were raised in an experimental poultry house up to 42 days of age at the School of Veterinary Medicine and Animal Science of UNESP, Botucatu, Brazil. After slaughter, three males and three females in each breed in each of the established gross scores were selected. Their femora heads were submitted to gross examination, and subsequently the thighs were submitted to the Veterinary Hospital for radiographic analysis. Femora were also submitted to bone resistance, Seedor index, and dry matter content analyses. All these bone quality characteristics were different between males and females, independent of breed. Breeds presented similar behavior. It was possible to establish correlations between bone quality parameters, and confidence intervals for bone mineral density values, correlating them to femoral degeneration score, which allows characterizing femoral head lesions by radiographic optical densitometry

Stem cells in sexual and asexual reproduction of Botryllus schlosseri (Ascidiacea, Tunicata): an overview.

Botryllus schlosseri, a colonial ascidian reproducing both sexually and asexually, is an excellent model for the study of adult stem cells, since blastozooids, produced by budding, derive from a disc of stem cells of the parental atrial chamber and the overlying epidermis. In the colony, adult zooids undergo cyclical generation changes during which the adults die, are resorbed and then replaced by their buds which reach functional maturity and start filtering; at the same time, blood cell renewal takes place thanks to a new haemopoietic wave. Experimental procedures can evaluate the behaviour of stem cells during bud morphogenesis under different developmental constraints. For example, when all the zooids and buds of a colony are extirpated, zooids can derive from totipotent blood cells which aggregate on the walls of the blood vessels of the tunic. Stem cells can also be transferred from one colony to another through blood vessels during fusion of compatible colonies. Germ stem cells persist in a host colony so that heterochtonous offspring can be collected after many blastogenetic generations. The persistence of somatic stem cells alters the fusibility pattern of the colony. Pluripotent stem cells are also involved in the embryonic development of larval and juvenile organs; these embryonic cells were analysed and compared with bud stem cells for their potentials and gene expression