Experimental rabies virus infection of big brown bats (Eptesicus fuscus)

A captive colony of adult Big Brown Bats (Eptesicus fuscus) was experimentally infected with a rabies virus (RABV) variant isolated from the salivary glands of a naturally infected Big Brown Bat and passaged once through murine neuroblastoma cell culture. Bats were divided into 11 groups, which were composed of one to three noninfected and one to three infected individuals each. Twenty of 38 animals were infected intramuscularly into both left and right masseter muscles; they received a total of 10(3.2) median mouse intracerebral lethal dose (MICLD50) of Big Brown Bat RABV variant. Experimental outcome after viral exposure was followed in the bats for 140 days postinoculation (PI). Of 20 infected bats, 16 developed clinical rabies, and the mean incubation period was 24 days (range: 13-52 days). Three infected bats never seroconverted and succumbed early to infection (13 days). Four infected bats that survived until the end of the experiment without any signs of disease maintained detectable antibody titers until the third month PI, peaking between days 13 and 43, and consequent drop-off below the threshold for detection occurred by day 140. Limited excretion of virus in saliva of infected bats during the clinical course of disease was observed in two individuals on days 13 and 15 PI (<24 hr prior to onset of clinical illness). No bat-to-bat transmission of RABV to noninfected bats was detected.     

Extended incubation period of rabies virus in a captive big brown bat (Eptesicus fuscus)

Rabies virus incubation in bats is typically less than 180 days, yet longer incubation periods have been described. We report a 267-day incubation in a big brown bat (Eptesicus fuscus) exposed to rabies virus before entering our captive colony.     

Pathology and ultrastructure of an intranuclear bacilliform virus (IBV) infecting brown shrimp Crangon crangon (Decapoda: Crangonidae)

The brown shrimp Crangon crangon supports an important fishery in Europe (over 25000 t, valued at 80 million euros in 2000). Through the course of histopathological screening of crustaceans from the Clyde estuary, western Scotland, for the biological effect of contaminants, we have discovered a highly prevalent (up to 100%) non-occluded intranuclear bacilliform virus (IBV) infection in the hepatopancreatic tubule epithelia and midgut epithelia of wild C. crangon. This is the first report of an IBV in this family. We have termed this virus Crangon crangon bacilliform virus (CcBV). Histological and ultrastructural observations suggest that this virus is similar to other IBVs previously described from crabs and penaeid shrimps. The nuclei of virus-infected epithelial cells contained an eosinophilic, hypertrophied viroplasm that marginalised the chromatin of the host nucleus. Infected cells were often separated from their neighbouring cells and their nuclei appeared apoptotic. In heavily infected shrimp, apoptotic cells were expelled into the lumen of the hepatopancreatic tubule or the midgut. Following this stage, some hepatopancreatic tubules became degenerate, with remnants of the basement membrane and myoepithelial lining remaining. Transmission electron microscopy of hypertrophic nuclei revealed the presence of rod-shaped and cylindrical, envelope-bound virions. These virions did not form arrays and were not embedded within occlusion bodies, but did appear to be partially occluded in an amorphous matrix that corresponded to a granular viroplasm. The ultrastructure, morphology and size of the nucleocapsid and the complete virion aligns the virus most closely to the IBVs previously reported from other decapod crustaceans. Due to the pathological manifestation of IBV infection in C. crangon, it appears likely that it can act as a population modulator, particularly at sites where infection prevalence is high, such as that observed in the Clyde estuary.     

Characterization of a novel satellite virus and a strain of Himetobi P virus (Dicistroviridae) from the brown planthopper, Nilaparvata lugens

Two distinct spherical virus-like particles were purified from the brown planthopper, Nilaparvata lugens. One was a geographical isolate of Himetobi P virus (Cripavirus, Dicistroviridae). The other was 30 nm in diameter and contained positive-stranded RNA. The RNA was 1647 nucleotides in length and encoded only its own capsid protein, indicating that this particle is a satellite virus. Transmission tests showed that the satellite was transmitted vertically; however, its helper virus was unknown. We named this satellite Nilaparvata lugens commensal X virus (NLCXV).     

European brown hare syndrome virus in free-ranging European brown hares from Argentina

From 1998 to 2000, serum samples of 80 shot European brown hares (Lepus europaeus) from Argentina were examined for antibodies against European brown hare syndrome virus (EBHSV) and 80 spleen samples were tested for EBHSV-antigen by enzyme linked immunosorbent assay (ELISA). Nine hares were positive for EBHSV-antigen. Antibodies against EBHSV were detected in only one individual. Based on negative staining electron microscopy of spleen homogenates, we observed calicivirus in one of five EBHSV-antigen positive hares. However, EBHS has not been reported to cause abnormal mortality in these hares. This is the first report of antibodies to EBHSV, EBHSV-antigen, and electron microscopy findings in free-ranging European brown hares from South America.     

A possible virus infection in the brown algaPylaiella littoralis

Summary Virus-like particles are described which occur in the unilocular sporangia of the marine brown algaPylaiella littoralis. The particles are hexagonal in the ultrathin section, 130–170 nm in diameter and resemble virus-like particles and true viruses seen in other organisms. Sporangia which contain virus-like particles exhibit various inclusions and modifications, such as dark-staining areas in the nucleus and membranous components in the cytoplasm, which are not seen in uninfected sporangia and which may be involved in the development of the particles.     

The cytology of oxalis dispar (brown)

Summary The chromosome complement ofOxalis dispar 2n = 12 consists of a pair of submedian (SM) chromosomes, three subterminal (ST) and seven telocentric (TE) chromosomes. At mitosis and meiosis the TE chromosomes are as efficient and stable as the other chromosomes of the complement. Chromosome breakage at the centromere in the metacentric chromosomes may give rise to new TE chromosomes. It is suggested that all the TE chromosomes may have arisen from metacentric chromosomes in this way. They may have been favoured because of the deleterious nature of the discarded chromosome arms.     

Suckling behaviour in the brown long-eared bat (Plecotus auritus)

Thirty-two adult female brown long-eard bats were taken into captivity. Eight individuals gave birth to single young in captivity (known mother-young pairs), 10 were lactating when captured (putative mother-young pairs), and the remaining 14 bats were non-reproductive. Bats were maintained in five groups consisting of females from sigle(n=3) or mixed (n=2) wild roosts. All bats were housed in outdoor, free-flight enclosures and fed mainly on free-flying noctuid moths. Bats were individually were determined daily (n=152) for a single gruup of bats containing four known mother-young pairs and five non-reproductive bats. The probability of a being attached to the nipple declined from 100% of records at 1-5 days of age to 5% of records at 36-40 days of age. Females were always found suckling their own young. Suckling associations were determined using infra-red sensitive video-recordings of bat behaviour within the roost box. For both known (n=8) and putative mother-young pairs (n=10), there were no records of young attached to lactating females other than their own mothers (from the same or different wild roosts).     

New records of brown algae (Phaeophyta) from the Azores

The following five species of microscopic tuft-forming/encrusting brown algae (Phaeophyta) are newly recorded for the Island of São Miguel (Azores): Nemoderma tingitana Schousboe ex Bornet, Pseudolithoderma roscoffense Loiseaux (Lithodermataceae), Hecatonema terminalis (Kützing) Kylin (Punctariaceae), Compsonema saxicolum(Kuckuck) Kuckuck, and Microspongium gelatinosum Reinke (Scytosiphonaceae). The species are described, and information is presented on their ecology and distribution around the island.     

Focusing and accommodation in the brown kiwi (Apteryx australis)

Summary Brown kiwis are an endangered species of nocturnal, flightless birds which are native to New Zealand. The resting focus of two specimens has previously been studied by retinoscopy in a zoo while the birds were restrained by their keeper (Sivak and Howland 1987). Those birds appeared to be hyperopic (farsighted) by 2–7 D. In this study, examination with infrared photorefraction of the focusing of two unrestrained, feeding birds showed that they could focus objects at infinity and objects in their immediate environment and that they had modest powers of accommodation. Measurements on two 6 month old kiwi chicks showed their corneal radius of curvature to be between 2.90 and 3.00 mm (117 D and 101 D in power).     

A natural asymptomatic herpes B virus infection in a colony of laboratory brown capuchin monkeys (Cebus apella)

Herpes B virus (BV) infection of macaques persists in the natural host, but is mainly asymptomatic. However, BV can cause fatal disease in humans and in several non-macaque species such as capuchin monkeys (Cebus apella). The BV infection described here in a colony of capuchin monkeys was persistent but asymptomatic. Initially the infection was detected serologically in five out of seven animals. However, using polymerase chain reaction (PCR) developed specifically for BV, we found the virus in all seven clinically healthy animals. It is probable that the infection was transferred from BV-infected macaques housed in different cages but in the same room for several years. We have no evidence to indicate that similar asymptomatic infections may occur in other New World species but the possibility should not be discounted. We recommend that the housing of capuchin monkeys in close proximity to macaques should be avoided and that greater caution should be used when handling capuchin monkeys and possibly other New World species that have been in contact with macaques. All may act as a source of BV infection in humans, hence routine, repeated testing of all primates is essential.     

Sexual behavior in brown capuchins (Cebus apella)

We observed sexual behavior patterns in two captive groups of Cebus apella.We obtained data on intersexual solicitations and intersexual competition. The length of proceptivity cycles by females averaged 18.8 ± 1.2 days; this corresponds with published reports of physiological measures of ovulatory cycles. Females initiated sexual interactions with males significantly more than males initiated interactions with females, and female solicitations increased in frequency over the duration of displayed periods of proceptivity. In contrast, male solicitations of females were infrequent and did not change significantly throughout female proceptive phases. Each female solicited the same male throughout a given proceptive phase. We observed no evidence of male-male or female-female competition. Males seem to respond to female sexual behavior directed toward them, rather than initiating sexual interactions themselves. Even so, male sexual interactions with females followed only a small proportion of solicitations.     

A tumorlike papilliform growth in the brown shrimp (Penaeus aztecus)

A brown shrimp, Penaeus aztecus, from an experimental pond of the Texas Parks and Wildlife Department's Marine Laboratory at Palacios, Texas, possessed a papilliform tumorlike growth on the right ventrolateral aspect of the sixth abdominal segment. Gross and histological study revealed the lesion to be confluent with the carapace, epidermis, and subepidermal connective tissue. The growth, tentatively diagnosed as a benign neoplasm, consists of grossly hypertrophied and normal tissue elements.     

Haemolytic activity in the brown shrimp (Penaeus californiensis holmes) haemolymph

• 1.1. Natural haemolytic activity in brown shrimp (Penaeus californiensis) haemolymph was detected using mouse erythrocytes as target cells. This activity is unrelated to agglutinating and phenoloxidase activity, but it is another probable component of the shrimp defence system.
• 2.2. The haemolytic reaction is time and dose dependent, and a serine-protease is involved.
• 3.3. The haemolytic factor is thermolabile and has an apparent molecular weight of 23.5 kDa.