Serum chemistry of bowhead whales (Balaena mysticetus).

Sera of 19 male and female bowhead whales (Balaena mysticetus) collected near Barrow, Alaska (USA) between 30 August and 13 October 1992 were evaluated for 18 serum chemistry values. Male bowhead whales had significantly greater creatinine and sodium concentrations, and significantly lower glucose concentrations than females. Pregnant females had greater triglyceride levels than non-pregnant females. The mean concentrations of creatinine, blood urea nitrogen, alkaline phosphatase, total bilirubin, total protein, sodium, potassium, chloride, phosphorus, and calcium were similar to those previously reported from bowhead whales. High aspartate aminotransferase and creatinine kinase levels were attributed to muscle damage associated with harpooning.

Intestinal volvulus in a bowhead whale, Balaena mysticetus.

An adult female bowhead whale, Balaena mysticetus, from the Beaufort Sea, Alaska (USA), had necrosis of a well-demarcated portion of the mid-jejunum and adjacent mesentery, accompanied by fibrinous peritonitis. The veins within the mesentery adjacent to the affected intestine were severely dilated and hyperemic. There were no perforations of the gastrointestinal tract, nor any thromboses within the mesenteric veins. Death appeared due to the sequelae of intestinal volvulus and infarction; reduction of the displacement presumably occurred during handling of the animal.

Microflora associated with the skin of the bowhead whale (Balaena mysticetus).

A study of the microbiological flora isolated from cultures of normal and lesional skin tissue samples collected from 19 bowhead whales (Balaena mysticetus) over a 4 yr period is presented. These cultures were obtained from 30 tissue samples (17 normal, 13 lesion) and 248 swab samples (157 normal, 91 lesion). Seven hundred-thirty bacterial and yeast isolations were made (285 normal, 445 lesion). Distribution revealed that 56% of the gram positive bacterial isolates, 75% of the gram negative bacterial isolates and 64% of the yeast isolates recovered were associated with lesional skin. It was found that 80% of one group of Corynebacterium sp. isolates, 90% of the Acinetobacter sp. isolates and 94% of the Moraxella sp. isolates were associated with lesional skin. Although the primary yeasts recovered were Candida spp., they were found on both normal and lesional skin. Enzymatic assays of isolates from normal and lesional skin demonstrated production of enzymes capable of causing necrosis. The majority of the microorganisms recovered were facultative anaerobes and many of them could be considered potential pathogens of mammalian hosts.

Observations on the anatomy of the stomach and duodenum of the bowhead whale, Balaena mysticetus.

Gastric and cranial duodenal structure of the bowhead whale (Balaena mysticetus) was examined grossly and microscopically. The stomach was arranged in a series of four compartments. The first chamber, or forestomach, was a large nonglandular sac lined by a keratinized stratified squamous epithelium. It was followed by the fundic chamber, a large, somewhat globular and entirely glandular compartment. At the entrance of the fundic chamber, a narrow cardiac gland region could be defined. The remaining mucosa of the chamber contained the proper gastric glands. A narrow, tubular connecting channel, the third distinct gastric division, was lined by mucous glands and joined the fundic chamber with the final stomach compartment, or pyloric chamber. This fourth chamber was also tubular and lined by mucous glands but was of a diameter considerably larger than the connecting channel. The stomach terminated at the pyloric sphincter which consisted of a well-developed band of circular smooth-muscle bundles effecting a division between the pyloric chamber and small intestine. The small intestine began with the duodenal ampulla, a dilated sac considerably smaller than the fundic chamber of the stomach. The mucosa of this sac contained mucous glands throughout. The ampulla led without a separating sphincter into the duodenum proper which continued the intestine in a much more narrow tubular fashion. The mucosal lining of the duodenum was composed of villi and intestinal crypts. Although their occurrence varied among whales, enteroendocrine cells were identified within the mucous glands of the cardiac region, connecting channel, pyloric chamber, and cranial duodenum. The hepatopancreatic duct entered the wall of the duodenum shortly after the termination of the duodenal ampulla and continued intramurally along the intestine before finally joining the duodenal lumen.

Serology and virology of the bowhead whale (Balaena mysticetus L.).

Sera from four bowhead whales (Balaena mysticetus L.) were examined for the presence of specific antibodies, and tissue and swab samples from six and four animals respectively were processed for isolation of viruses and for initiation of bowhead whale cell cultures. All sera were negative for antibodies to nine serovars of Leptospira interrogans and to 21 orthomyxovirus subtypes and a paramyxovirus (Newcastle disease virus). All sera were positive, however, for neutralizing antibodies to one or more calicivirus serotypes. Two untyped adenoviruses were isolated from colon samples of two different whales, but neutralizing antibodies to the agents could not be demonstrated in any sera. Three primary bowhead whale cell cultures were derived from kidney (two cultures) and testis (one culture), from three individual whales.

Microanatomy of the renicule of Balaena mysticetus.

Renicules from twelve bowhead whales (Balaena mysticetus) were examined utilizing light, scanning electron, and transmission electron microscopes. The basic organization of the renicule into capsule, cortex, sporta perimedullaris, medulla, and calyx is described. Despite less than perfect preservation resulting from environmental and logistical conditions at the collecting sites, it has been possible to document the basic microstructure of most components of the renicule of this endangered species. Several unusual features were observed. The absence of smooth muscle fibers (other than in vessel walls) from the capsule, sporta perimedullaris, and calyx wall is a departure from what is reported in other cetaceans as is the consistent presence of arcuate arteries in the substance of the sporta perimedullaris. Large subcapsular veins are present but do not appear to represent connecting elements in an alternative venous return through capsular and interrenicular veins. Elastic fibers are seen only in the sporta perimedullaris and the calyx wall, whereas reticular fibers are most abundant in the medullary stroma. Finally, enlarged cells with clear cytoplasm are seen in the tunica media of the glomerular afferent arterioles extending a variable, but always considerable, distance toward the interlobular arteriole. These cells are presumed to represent an extended array of the epithelioid cells common in the afferent arterioles of the juxtaglomerular apparatus of other mammalian kidneys.

Epidermal and papillary dermal characteristics of the bowhead whale (Balaena mysticetus).

Skin samples from most body regions of the bowhead whale were examined. The epidermis is 2.7 to 50 times thicker than that reported in other cetaceans with both regional and individual variations in thickness. The thinnest areas examined (1 mm) occur on the eyelid margins and the thickest (25 mm) occur on the lower jaw. A distinctive parakeratotic stratum corneum with a thick underlying stratum spinosum (without a stratum granulosum) extends over the entire body surface. From a few dozen to several hundred epidermal lesions are present on all whales studied. A typical stratum basale of germinative keratinocytes (with melanocytes in pigmented areas) rests upon a well-defined basal lamina. Epidermal rod arrays arise from the basal keratinocytes which cover highly elongated dermal papillae and extend to the epidermal surface through the distal stratum spinosum and the stratum corneum. At least four diatom genera occur on and in the stratum corneum and lesion areas of different whales. The superficial dermis consists of a papillary layer with long (up to 13 mm) dermal papillae interdigitating with the epidermis from a basal area that is 2-4 mm in thickness. The number of dermal papillae per mm2 varies inversely with the thickness of the epidermis. Large diameter, sensory papillae packed with tortuous, highly elongated, encapsulated nerve end organs also interdigitate with the thin epidermal areas of the ventral surface of the rostrum, the upper and lower lip margins, and the upper and lower eyelid margins. Scattered, single, stiff hairs emerge from the skin only in specific, pigmented regions of the head.

Microanatomy of the major airway mucosa of the bowhead whale, Balaena mysticetus.

In the bowhead whale, Balaena mysticetus, the mucosa of the major airways from the blowholes through the rostral portion of the larynx is lined with parakeratotic, pigmented, stratified squamous epithelium. Scattered enlarged connective tissue papillae of the lamina propria of the nasal vestibules and the palatopharyngeal sphincter contain encapsulated nerve endings. Abundant papillae in the mucosa covering the epiglottic and arytenoid cartilages contain similar nerve endings. The remainder of the laryngeal cavity and laryngeal sac is lined by a variably pigmented, stratified squamous epithelium, which is not keratinized. At the laryngotracheal junction the lining changes to ciliated pseudostratified columnar epithelium which continues through the trachea and principal bronchi. Scanning electron microscopy (SEM) indicates that this epithelium is typically mammalian, with approximately half of the surface cells bearing cilia and slender microvilli. The remaining cells are mucus producing and have thicker microvilli. The valvular mass regulating the external nares consists of irregular, dense white fibrous connective tissue with numerous adipose cells and is penetrated by skeletal muscle cords ranging from 2-4 mm in diameter. The septal mass between the blowholes is composed of irregular, dense white fibrous connective tissue containing large tendinous bundles, clusters of adipose cells, and several large arteries and thick-walled veins. The lamina propria of the nasal vestibules is irregular, dense white fibrous connective tissue. That of the larynx is not as dense and contains proportionately more elastic fibers. The laryngeal sac does not contain elastic laminae, but does have a tunica muscularis of skeletal muscle bundles. Within the trachea and principal bronchi, the lamina propria possesses laminae of longitudinally oriented elastic fibers and simple, branched tubuloalveolar mucous glands. The nasal, laryngeal, tracheal, and bronchial cartilages are hyaline with vascular channels.

Macroanatomy of the renicule of the bowhead whale (Balaena mysticetus).

The macroanatomy of renicules and surrounding tissues from the kidneys of five Eskimo-harvested bowhead whales, Balaena mysticetus , was examined. These renicules are similar in overall structure to those of other cetaceans and intermediate in size. There are several important differences including the presence of arcuate vessels within the sporta perimedullaris , the extension of connective tissue from the sporta deep into the peripheral cortex, and the presence of very large, thin-walled veins that occupy the interrenicular spaces. Arterial and venous plexuses outside the substance of the sporta reported in other cetaceans were not observed in the bowhead .

Gross anatomy of the respiratory system of the bowhead whale, Balaena mysticetus.

Components of the respiratory system from seven bowhead whales have been examined. The paired and laterally curved external nares are passively closed by a valve-like mass located in the rostral, lateral, and ventral walls of the nasal vestibules. Nasal septal cartilages are paired smooth plates rostrally changing to accordion-like folds caudally. The epiglottic and arytenoidal protuberances of the larynx are typically cetacean, but blunt. The cricoid cartilage is not a complete ring, but an elongated, inverted, trough-shaped structure. The thyroid cartilage is trough-shaped with elongated cranial cornua curving dorsocaudally from each thyroid lamina. A conical mass of skeletal muscle serves as the floor of the short trachea and also surrounds the termination of the laryngeal sac. The trachea is dorsoventrally compressed, lacks a tracheal bronchus, and its width equals its length. The principal bronchi give rise to lobar bronchi at obtuse angles. Large segmental bronchi branch extensively from lobar bronchi near the mediastinal lung surface. The lungs are rectangular and of nearly uniform thickness throughout, without external or internal lobulation.

Isolation of a herpesvirus from the cell culture of a malignant melanoma of a ground squirrel (Spermophilus tridecemlineatus).

A subcutaneous neoplastic mass in a 13-lined ground squirrel which metastasized to regional lymph nodes and lung was studied. Histopathologically, the tumor architecture and cellular morphology were compatible with that of a malignant amelanotic melanoma. Ultrastructurally, the neoplastic tissue was composed of oval cells, spindle-shaped cells, and spindle-shaped cells with electron-dense cytoplasmic granules. Virus particles were not seen in these cells. Cell cultures from neoplastic tissue grew in complete monolayers and on initial passages contained a few herpesvirus particles. Secondary monolayer cell culture, when exposed to 5-iodo-2'-deoxyuridine or made into several serial subculture passages, caused the appearance of cytopathic effect and the demonstration of many virus particles. The ground squirrel agent, because it contained DNA, was sensitive to chloroform treated and had herpesvirus characteristics on electron microscopy, was considered a herpesvirus. The buoyant density of the virus was 1.298 g/cm3 and the diameter of the enveloped virus particles was 146 nm. This ground squirrel herpesvirus was antigenically distinct from other known herpesviruses.

Permanent outdoor housing for woodchucks, Marmota monax.

Permanent outdoor housing for woodchucks (Marmota monax) was constructed from chain link fencing sections on a concrete base. Metal poultry nest boxes were attached to 1 side of the cage. Each enclosure accommodated up to 10 woodchucks and provided adequate shelter and exercise space. This housing system was inexpensive to construct and efficient to service.

Health and performance of calves with forestomach-bypass fed milk replacer.

Ten male Holstein calves were placed in groups of two calves each on similarity of age. On calf in each group was subjected to forestomach-bypass surgery at about 1 mo of age. Fortified commercial milk replacer with added minerals and vitamins was fed as the sole diet. The calves were housed indoors on slatted platforms. Weight gain was determined biweekly. Feed intake was determined daily. Necropsies were performed upon termination of the study. Recurrent ruminal bloat, fever, and anorexia of varying degrees and combinations occurred in four of the calves with forestomach bypass. Two of these calves showed slow weight gain. One of the four calves died following acute bloat while the other three calves were sacrificed following repeated episodes of bloat. The time of termination varied between 3 and 10 mo. One calf with forestomach bypass and all control calves appeared healthy throughout the experiment. Necropsies indicated that the ruminal bloat, seen in most of the forestomach-bypass calves, could be attributed to the back-flow of ingesta via the omasal-abomasal orifice. This ingesta appeared to produce gas which became trapped in the bypassed rumen.

Ocular changes in a horse with gutturomycosis.

Recurrent epistaxis and locomotor and visual disturbances leading to blindness in a 7-year-old gelding appeared to have resulted from a spreading fungal granuloma of the guttural pouch. The inflammatory area extended to the intracranial segment of the right optic nerve and to the region adjacent to the optic chiasma. Microscopically, changes indicative of multiple foci of ischemic infarction were noticed in the retina, optic nerves, optic chiasma, and optic lobe. The profusely growing fungal elements in the guttural granuloma had the morphologic characteristics of an Aspergillus sp.

Left displacement of the abomasum in a clinically normal cow.

A cow with left displacement of the abomasum (lda) was found to be clinically normal for 1 1/2 years. During this period, the cow calved twice and ate and produced milk normally. Auscultation and percussion at approximately weekly intervals revealed the continuing abomasal displacement, which was confirmed at necropsy.