Pneumatosis cystoides intestinalis in a rabbit doe (Oryctolagus cuniculus).

Pneumatosis cystoides intestinalis (PCI) is an infrequent condition of animals characterized by the existence of numerous thin-walled, gas-filled cystic structures within the intestinal wall and adjacent lymph nodes. Microscopically, the cystic structures appear to be dilated lymphatics located in the lamina propria, submucosa, muscularis, subserosa, mesentery, and mesenteric lymph nodes. This report describes a case of pneumatosis cystoides intestinalis in a rabbit doe from an organic farm where 20 rabbit does were fed ad libitum with a natural diet consisting of whole barley, pea beans, alfalfa hay, and a pelleted vitamin-mineral blend. A combination of nutritional, bacterial, and other factors are hypothesized as possible predisposing factors in the development of PCI.     

Use of avidity enzyme-linked immunosorbent assay and avidity Western blot to discriminate between acute and chronic Neospora caninum infection in cattle.

Avidity serological tests (avidity enzyme-linked immunosorbent assay [ELISA] and avidity Western blot) were developed and used to differentiate between acute (primary infection, reinfection, and recrudescence) and chronic Neospora caninum infection in cattle. In addition, the pattern of immunoglobulin G (IgG) avidity maturation against different specific antigens of N. caninum tachyzoites was studied. Sequential serum samples were collected from cattle naturally and experimentally infected with N. caninum. Four groups of experimentally infected cattle were included in the study and were representative of primary infection, reinfection, chronic infection, and noninfection. Serum samples were also collected from naturally infected cattle classified into nonaborting and aborting cows on the basis of clinical findings and serological profiles, and a third group composed of seronegative cows that seroconverted during the course of the experiment. All samples were tested by avidity ELISA and avidity Western blot. The IgG avidity ELISA allowed the discrimination between primary and chronic infection because all experimentally primary-infection cows showed low avidity indexes at week 4 postinfection (p.i.) compared with the high avidity values found at week 20 postinfection. However, this test did not allow the discrimination of reinfection or recrudescence from chronic infection. Regarding IgG avidity Western blot results, no antigenic markers correlating with acute (primary infection, recrudescence, and reinfection) or chronic infection were recognized. However, the 17-kD immunodominant antigen was mostly responsible for high avidity values obtained by avidity ELISA because it was intensively recognized by high-avidity antibodies in all chronically infected animals after urea treatment.     

Isolation of equine herpesvirus-2 from the lung of an aborted fetus.

This study describes the isolation of equine herpesvirus-2 (EHV-2) from the lung of an aborted equine fetus in Argentina. The isolated virus was confirmed as EHV-2 by indirect immunofluorescence using a rabbit anti-EHV-2 polyclonal antiserum and by virus-neutralization test using an equine polyclonal antibody against EHV-2. Restriction endonuclease DNA fingerprinting with BamHI also confirmed the identity of the virus as EHV-2. Furthermore, viral nucleic acid was detected by polymerase chain reaction from the original lung sample and from the DNA obtained from cells infected with the virus isolate. This work constitutes the first reported isolation of EHV-2 from an aborted equine fetus. The presence of EHV-2 in the lung of the aborted fetus would indicate that this virus is capable of crossing the placental barrier. However, no cause-effect relationship was established between the EHV-2 isolate and the abortion.     

An in vitro study of hematopoietic progenitor cells from peripheral blood of rabbits

The purpose of this study was to isolate and cultivate a subpopulation of pluripotent stem cells (PSCs) from the peripheral blood of rabbits, which are frequently used in veterinary research as an animal model. Pluripotent stem cells, as described in human beings, are fibroblast-like cells that exhibit a CD34 marker, specific from other hematopoietic stem cells. Commonly used human commercial media has been researched for culturing rabbit PSCs. These findings allow us to contemplate the direct application of this simple and standardized methodology in several areas of study, such as of the pharmacological effect of many drugs on hematopoietic cells, veterinary practice, and even the study of new strategies in cellular therapy for some human diseases.     

Evaluation of Natural Chemical Compounds Against Root-lesion and Root-knot Nematodes and Side-effects on the Infectivity of Arbuscular Mycorrhizal Fungi

The survival of two species of plant parasitic nematodes: the root-lesion nematode Pratylenchus brachyurus, and the root-knot nematode Meloidogyne javanica, was evaluated in saturated atmospheres of 12 natural chemical compounds. The infectivity of two isolates of arbuscular mycorrhizal fungi: Glomus mosseae and Glomus intraradices, under identical experimental conditions, was also determined. All the compounds tested exerted a highly significant control against M. javanica and among them, benzaldehyde, salicilaldehyde, borneol, p-anisaldehyde and cinnamaldehyde caused a mortality rate above 50% over P. brachyurus. The infectivity of G. intraradices was inhibited by cinnamaldehyde, salicilaldehyde, thymol, carvacrol, p-anisaldehyde, and benzaldehyde, while only cinnamaldehyde and thymol significantly inhibited mycorrhizal colonization by G. mosseae.     

Cropping systems for the management of phytonematodes

Damage caused by nematodes is one of the limiting factors in crop production. Traditional nematode management is based on the use of crop rotations, resistant cultivars, nematicides, or combinations of these methods. For a crop like peanut (Arachis hypogaea), cultivars resistant to root-knot nematodes are not available. There are soybean (Glycine max) cultivars resistant to some of the species of root-knot nematodes (Meloidogyne spp.); however, most fields have nematode infestations composed of mixtures of species. Research at Auburn has shown that tropical crops can be used effectively in rotation to manage nematode problems. Rotations with American jointvetch (Aeschynomene americana), castor (Ricinus communis), hairy indigo (Indigofera hirsuta), partridge pea (Cassia fasciculata), sesame (Sesamum indicum), and velvetbean (Mucuna deeringiana) have resulted in good nematode control and increased yields of peanut and soybean. Some crops (castor, sesame) are considered ‘active’ in that they produce compounds that are nematicidal, whereas others (e.g. corn, sorghum) are simply non-host, that is, ‘passive’.     

Field evaluation of the single intradermal cervical tuberculin test and the interferon-gamma assay for detection and eradication of bovine tuberculosis in Spain

A field comparison of the interferon-gamma (IFN-gamma) assay and the single intradermal cervical tuberculin (SICT) test for the diagnosis of bovine tuberculosis was conducted. A total of 1136 cattle belonging to 85 herds placed in 'Castilla y León' (northwestern Spain) were chosen, and 21 of these herds were subjected to the diagnostic assays two or three times at intervals of at least 4 months. All the animals positive to any of the tests were slaughtered and tuberculosis was confirmed by culture isolation method (CIM) and further identification by means of PCR. Only 10.6% of cattle reacted with the bovine PPD in the SICT test, a percentage that increased to 12.8% in the IFN-gamma assay. The sensitivity of the IFN-gamma assay compared to CIM was shown to be higher (84.9%) than that of the SICT test (80.2%), but the combination of both tests offered the highest sensitivity (92.9%). The number of false positive reactors (those animals in which CIM was negative) was considerably higher for the IFN-gamma assay than for the SICT test and, conversely, the number of false negative animals (M. bovis isolation but negative immunological result) was higher for the skin test than for the interferon assay. In the herds tested twice, tuberculosis was eradicated after the second cycle of testing in 50%, and in 75% after the third cycle in herds tested three times. The combination of these two techniques instead of separately seems, therefore, to be useful in eradication programmes against bovine tuberculosis.     

Studies on the transmission of Theileria annulata to cattle by the tick Hyalomma lusitanicum

The role of the ixodid tick Hyalomma lusitanicum Koch 1844 as a vector of Mediterranean or tropical theileriosis (caused by the protozoan parasite Theileria annulata Dschunkowsky et Luhs 1904) in southern Spain was studied. Hyalomma lusitanicum was the most common tick, and the only species of the genus Hyalomma L., found on T. annulata-infected cattle from the theileriosis enzootic area studied (province of Cádiz, southern Spain). Likewise, we found that all sera of the cattle previously considered as suspected of theileriosis by clinical signs, tested for T. annulata antibodies, were positive and all blood samples of these suspected cattle examined had infected erythrocytes. Partially fed H. lusitanicum adults were collected in the field on T. annulata-infected cattle in this enzootic area and fed on an uninfected calf in an experimental farm free of theileriosis and ticks. At approximately 3 weeks post-tick feeding on the calf, this became positive for T. annulata antibodies and T. annulata merozoites were found in erythrocytes from blood smears. These results show the ability of H. lusitanicum to transmit the protozoan parasite T. annulata to susceptible cattle and indicate that H. lusitanicum is probably an important vector of T. annulata in the enzootic area surveyed.     

Liver pathology and immune response in experimental Fasciola hepatica infections of goats

The relationship between the immune response and the pathogenesis of the disease was studied in different primary and secondary experimental Fasciola hepatica infections of goats. The establishment of the infection, measured as percentage of recovered flukes at the necropsy, was similar in primarily and secondarily infected animals (between 19.7% and 24.3%), but the hepatic damage was much more severe in secondarily infected goats, as revealed by the levels of serum hepatic enzymes GGT and LDH. Primary infection evolves to chronic fasciolosis that did not induce the development of resistance, since goats were highly susceptible to secondary infection, showing severe acute and chronic hepatic lesions that led to the death of some animals in each group. The immune response to the infection was proved by the production of specific IgG antibodies to ESP of F. hepatica and the involvement of CD3+ T lymphocytes and lambda IgG+ plasma cells in the hepatic infiltrate. Secondary infection did not induce any difference in either IgG response or in the cellular composition of the infiltrate of hepatic lesions, although this was much more extended. However, neither antibodies nor cell-mediated response were protective: there was no correlation between IgG levels and fluke burden and there was no evidence of cell-mediated killing of the parasite. This suggests the existence of some immune evasion mechanisms in goat infection with F. hepatica. The parasite may depress the local inflammatory and immune response, as suggested by the scarcity of CD3+ T cells in the infiltrate surrounding acute migratory tunnels. Moreover, in secondary infected goats can be suspected an immunological damage of the liver, since a very severe infiltrate of immune cells replaced wide areas of hepatic parenchyma and an immune-mediated damage of hepatocytes could occur.     

Lactation curves in captive Iberian red deer (Cervus elaphus hispanicus)

This study examines milk production and the effect of milk production and sex of calf on body weights and gains of red deer calves and hinds of the Iberian subspecies (Cervus elaphus hispanicus). Milk production was assessed in 14 hinds by weighing calves before and after suckling and by adjusting these values to the Gamma function. Gamma estimates of total milk production up to d 105 were similar to the amounts computed directly from double weighing. Hinds showed two types of lactation curve: 1) the standard mammal lactation curve, with an asymmetrical peak at wk 2 to 4 (Type I) and 2) decreasing curves with no peak (Type II). Although there was great interindividual variability, hinds with Type I curves showed a trend to produce more milk than those with Type II. The type of curve did not seem to affect weight variables of the calf or those of the dam. Calves that gained more weight consumed greater amounts of milk (P<.05). Males were heavier than females at birth (P<.05), but males did not differ from females in their weight at 105 d, milk consumption, and gain. Gender did not affect hind weight, but dams of male calves showed a trend to be lighter (P = .063) at d 105 than dams of female calves. Our results suggest that suckling differences found in other studies between male and female calves may not involve differences in milk production, although other rearing costs seem to affect hind weight losses. They also suggest that the curve type may not depend only, as reported, on the nutrition plane.