Faculty of Veterinary Medicine University of Zagreb
Abstract
This study investigated the effects of Trypanosoma brucei infection on post-partum (PP) uterine involution in the albino rat (Rattus norvegicus). Ninety-six rats (80 females and 16 males) were used for the study. The females were divided into 2 equal groups of 40 infected and 40 uninfected. The males which were uninfected were used for mating with the females. From each of the 2 female groups, 5 were humanely sacrifi ced daily from day 0 to day 7 PP. Body mass (BM), uterine mass (UM), uterine mass as a percentage of body mass (UMPBM), uterine histomorphology, packed cell volume (PCV), level of parasitaemia (LOP) and rectal temperature (RT) were evaluated in the females. Results showed that both the UM and the UMPBM of the infected rats were significantly higher (P<0.01) than those of the uninfected between days 1 and 7 PP. Uterine histomorphology showed that between days 3 and 7 PP, involution was more advanced in the uninfected group. Uterine sections of the infected rats had more glands, which were also larger in size. Endometrial stroma was less cellular in the uninfected rats and the myometrium showed higher nuclei density for myofi brils, which suggests some loss of cytoplasm. The PCV of the infected rats was significantly lower than that of the uninfected (P<0.01) between days 9 and 14 post-infection (PI), while the RT of the infected rats was significantly higher (P<0.01) than that of the uninfected between days 5 and 14 PI. It was therefore concluded that T. brucei infection led to a significant delay in PP uterine involution, as evidenced by the higher UM and UMPBM, and the uterine histomorphological findings in the infected rats.Istraživanje je provedeno s ciljem određivanja učinka protozoona Trypanosoma brucei na postpartalnu involuciju maternice u albino štakora (Rattus norvegicus). Za istraživanje je rabljeno 96 štakora (80 ženki i 16 mužjaka). Ženke su bile podijeljene u dvije jednake skupine tako da je 40 ženki pripadalo kontrolnoj, a 40 invadiranoj skupini. Neinvadirani mužjaci su poslužili za parenje. Iz svake skupine bilo je eutanazirano pet ženki i to svaki dan (od nultog do sedmog dana). Za svaku ženku bila je određena tjelesna masa, masa maternice, odnos mase maternice i tjelesne mase, histološki nalaz maternice, ukupan broj krvnih stanica, razina parazitemije i rektalna temperatura. Rezultati su pokazali da je u invadiranih štakorica maternica bila značajno teža kao što je bila i značajno veća masa maternice u odnosu na tjelesnu masu ženke (P<0,01) u razdoblju od prvog do sedmog dana nakon partusa. Histološkom pretragom dokazano je da je involucija maternice u razdoblju od trećeg do sedmog dana bila izraženija u neinvadiranih ženki što je dokazano i većim brojem povećanih žlijezdi. Stroma endometrija neinvadiranih životinja sadržavala je manje stanica. U miometriju je dokazana veća gustoća jezgara u miofibrilima što govori u prilog gubitku citoplazme. Ukupan broj krvnih stanica u invadiranih štakorica bio je značajno manji u odnosu na neinvadirane (P<0,01) u razdoblju od devetog do četrnaestog dana nakon invazije. Invadirane štakorice imali su višu tjelesnu temperaturu (P<0,01) u razdoblju od petoga do četrnaestoga dana. Na temelju postignutih rezultata zaključuje se da invazija vrstom Trypanosoma brucei dovodi do značajnog kašnjenja involucije što je potvrđeno većom masom maternice, većom masom u odnosu na tjelesnu masu te histomorfološkim nalazom u invadiranih ženki
