Consideraciones sobre el sistema urinario del Gallus gallus– Indian River; I. Formación y tributaris del uréter

In the literature reviewed, there are certain differences of opinion with regard to the formation and tributareis to the ureter. Therefore, dissection of 40 fowls injected with neoprene latex, k neoprene latex and celobar (radiopaque mass) and vinyl acetate casts through the ureter and blood vessels revealed the formation and disposition of the tributaries to the ureter, and its origin and number of collectors. The results were described in relation to the renal lobes.     

Fiber Types Distribution in the Digastric Muscle of Tufted Capuchin Monkey (Cebus apella)

Fiber types distribution in the diagastric muscle of tufted capuchin monkey was studied by means of NADH-TR, myosin-ATPase, after alkaline and acid preincubations and SDH histochemical reactions. Three different types of fibers were found presenting an equal distribution. The percentage and types of fibers were as follow: 18.2 % SO (Slow Oxydative), 38.4 % FOG (Fast Oxydative Glycolytic) and 43.4 % FG (Fast Glycolytic). FG fibers revealed the largest area. The relatively high concentration of fast twitch (81.2 %) seems to indicate this muscle is involved with the acceleration and fast speed of jaw movements. Aerobic metabolism represented by SO + FOG fibers (56.6 %) suggestes that this muscle possesses an additional role than that related to the lowering of the jaw.     

Studies on the antigenic relationships of six adherent isolates of Bordetella bronchiseptica

Six isolates of Bordetella bronchiseptica recovered from swine with atrophic rhinitis were studied. All hemagglutinated swine red blood cells, autoagglutinated in saline and showed fimbriae by electron microscopy. Hyperimmune sera against each were produced in rabbits and the antigenic relationships between the isolates were studied by cross-absorption and by the determination of the cross-reactivity indices of pairs of sera. Three isolates seemed to be identical by both methods, while 2 others showed close antigenic relationships. Hemagglutination titers with heterologous antigens and cross-reactivity indices greater than 0 suggest some degree of cross-immunity among the isolates studied, even when antigenic heterogeneity was demonstrated.     

Diarrhoea in Merino ewes during winter: association with trichostrongylid larvae

SUMMARY A study on 3 farms, each having a preventive strategy for the control of nematode infections, determined the risk factors associated with diarrhoea among Merino ewes in winter. Comparisons were made among groups of mated and unmated ewes with and without treatment with controlled-release capsules containing albendazole. Diarrhoea was assessed from the accumulations of faeces around the breech (dag score) and related to worm egg counts, total worm counts and histopathological findings. The overall prevalence of severe dag in ewes not treated with a capsule was 26% (221/844). In comparison, only 2.7% of treated ewes had severe dag. The adjusted odds ratio on each farm indicated that untreated ewes were between 12 and 16 times more likely to be affected with severe dag than ewes treated with a capsule. The effect of lactation was significant on only one farm whereas initial body weight had no significant effect. There was no significant association between worm egg counts and the occurrence of severe dag. There were significantly more eosinophils in the small intestine of ewes affected with severe dag compared with unaffected ewes. There were no significant differences in mast cell and globule leucocyte numbers between affected and unaffected ewes. This study provides strong evidence that the main cause of diarrhoea among Merino ewes grazing winter and early spring pastures is the ingestion of trichostrongylid larvae even by sheep that have a well-developed protective immune response to these parasites. New strategies for the control of nematode infections are needed to prevent diarrhoea and dag formation in adult sheep.     

The development of a viral antigen in the hemocytes ofPieris brassicae inoculated withTipula iridescent virus

Positive reactions in micro-precipitation tests showed the serological relationship between theTipula iridescent virus (TIV) fromTipula paludosa andPieris brassicae. In gel diffusion tests, the results were negative. Applying the fluorescent antibody technique the first fluorescent particles in the proleucocytes and amoebocytes ofP. brassicae were observed on the third day after infection with TIV. On the seventh day the hemocytes having reached their maximum size, were swollen and completely filled with the viral antigen. In the healthy larvae of the same age, the hemocytes appeared to be normal.     

Populational dynamics of Stomoxys calcitrans (Linneaus) (Diptera: Muscidae) in three biocenosis, Minas Gerais, Brazil

Populational flux of the adult phase of Stomoxys calcitrans was observed in the municipal district of Pedro Leopoldo, Minas Gerais, Brazil. Three biocenoses were selected for the study: stable agrobiocenosis, pastural agrobiocenosis and eubiocenosis. The occurrence and the populational flux of the insects, using the Magoon trap for their capture, were established. For each trap located in different biocenoses, a crossbred calf (Bos taurus × Bos indicus) approximately 6-month-old was used as “live bait,” exposed weekly for 48 h in the traps. Of the three agrobiocenoses studied, the stable agrobiocenosis contributed the greatest number of specimens of. S. calcitrans captured, corresponding to 96.9% of the total flies of this species collected. S. calcitrans shows seasonal behavior for approximately 6 months (spring and summer being the rainiest months of the year). The population peaked during the months of November and December. During the months of July and August, there was no capture of flies.     

Morphological, histological, and ultrastructural studies of the ovary of the cattle-tick Boophilus microplus (Canestrini, 1887) (Acari: Ixodidae)

This study presents the morphology of the ovary, as well as the dynamics of the vitellogenesis process in oocytes of the cattle-tick Boophilus microplus. The ovary of these individuals is of the panoistic type; therefore, it lacks nurse cells. This organ consists of a single tubular structure, continuous, and composed of a lumen delimitated by a wall of small epithelial cells with rounded nuclei. In this tick species, the oocytes were classified into six stages varying from I to VI and according to: cytoplasm appearance and presence of the germ vesicle, yolk granules, and chorion. Oocytes of various sizes and at different developmental stages remain attached to the ovary through a cellular pedicel until completing stage V. Afterwards, they are liberated into the lumen and from there to the exterior. Some oocytes (classified as type VI) showed an atypical appearance indicating that some of the cellular components would be undergoing a degenerative process and/or reabsorption.     

Leukocyte-hepatocyte interaction in calicivirus infection: differences between rabbits that are resistant or susceptible to rabbit haemorrhagic disease (RHD)

Calicivirus infection is lethal for adult rabbits, whereas young rabbits (less than 8-weeks-old) are resistant to the same infectious agent. The virus replicates in the liver and causes a fulminant hepatitis in adult rabbits leading to rabbit haemorrhagic disease (RHD); this is in contrast with the mild and transient hepatitis observed in infected young rabbits. We have used electron microscopy to compare liver leukocyte infiltrates between young (resistant) and adult (susceptible) rabbits, 36-48 h after inoculation of the animals with caliciviruses. In adult rabbits, liver infiltrates were made up mostly of heterophils, and they were located near hepatocytes showing severe cellular damage. In contrast, liver leukocyte infiltrates of RHD-resistant young rabbits were dominated by lymphocytes that depicted membrane contacts with the cell surface of undamaged hepatocytes. We conclude that: (i) the cellular inflammatory response of the liver to calicivirus infection is different in rabbits that are susceptible (adult) or resistant (young) to RHD; (ii) leukocyte infiltration of the adult liver by heterophils is probably directed at the removal of dead hepatocytes, whereas the liver lymphocytic infiltration of young rabbits suggests the expression of viral antigens on the surface of liver cells of the RHD-resistant animals.     

Clinical disorders observed in anteaters (Myrmecophagidae,Edentata) in captivity

The major health problems found in 103 captive lesser anteaters (Tamandua tetradactyla) and giant anteaters (Myrmecophaga tridactyla), family Myrmecophagidae, are presented and correlated with management. The most common of 200 recorded clinical disorders involved the digestive system (26%), nutritional deficiency (20%), injury (15.5%), respiratory system (10%), skin (7%) and circulatory system (4.5%), but 13% of the cases were inconclusive. Parasites were identified in 48.5% of faecal samples, mainly the eggs of nematodes (40%), of which the commonest wereTrichuris spp (28%) andStrongyloides spp (11%); protozoa (16%), of which the commonest wereEimeria spp (10%),Entamoeba spp (5%) andGiardia spp (1%); and cestodes (8%) and acanthocephalids (1%). Bacteria cultured from the various materials includedSalmonella enteritidis, S. cholerasuis, Escherichia coli, Enterobacter aerogenes, Streptococcus spp andStaphylococcus spp. The ectoparasites found wereAmblyomma spp andOtodectis spp (Arthropoda, Acaridae).