Histological alterations in the liver of sea bream, Sparus aurata L., caused by short-or long-term feeding with vegetable oils. Recovery of normal morphology after feeding fish oil as the sole lipid source A short-term trial (3 months) and longterm trial (6 months) were carried out feeding sea bream with the following experimental diets: FO100%; SO60% + FO40%; RO60% + FO40%; LO60% + FO40%; SO + RO + LO60% + FO40%. Finally, all groups from the long-term trial were fed with FO100% for 95 days (washout period). Liver samples were taken for histological and biochemical studies. In both the short-and long-term trials, livers of sea bream fed LO60% and SO + RO + LO60% showed a similar hepatic morphology to that observed in fish fed FO100%. In contrast, sea bream fed SO60% showed an intense steatosis, with foci of swollen hepatocytes containing numerous lipid vacuoles. After the washout period, a considerable reduction of the cytoplasmic vacuolation and the lipid vacuole accumulation were observed in the livers of fish fed the different experimental diets. The results of this study suggested that the type of non-essential fatty acid, characteristic of vegetable oils, induces the appearance of steatosis in the following order: linoleic acid > linolenic acid > oleic acid. However, the liver alterations found during the experimental periods with vegetable oils are reversible when the fish are re-fed with a balanced diet (FO100%), indicating the non-pathological character of these histological changes.

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Abstract. This article describes the gross, histopathologic, and ultrastructural findings of the livers of cetaceans stranded on the coast of the Canary Islands between 1992 and 2000. A total of 135 cetaceans were included in the study, among which 25 were common dolphins (Delphinus delphis), 23 Atlantic spotted dolphins (Stenella frontalis), 19 striped dolphins (Stenella coeruleoalba), and 15 other species of dolphins and whales. The most common lesion observed in these animals was a nonspecific chronic reactive hepatitis (47/135), followed by hyaline intracytoplasmic inclusions in hepatocytes (33/135). Parasitic cholangitis was detected in 8/135 animals, whereas hepatic lipidosis was presented in 7/135 animals. The ultrastructure of hyaline hepatocytic cytoplasmic inclusions is described, and possible causes of these inclusions are discussed.Key words: Cetaceans; dolphins; hepatic lesions; liver; ultrastructure.Information on cetaceans found stranded on the coast of the Canary Islands has been collected by the Histology and Pathology Unit of Las Palmas of Gran Canaria University during an 8-year period (1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000). One hundred and thirty-five cetacean strandings occurred on the shores of these islands, involving both single and multiple strandings of adults and juvenile cetaceans, but to date there have been no surveys of the causes of illness in the wild, free-living dolphin and whales found dead in the Canary Islands.In the study of the stranded cetaceans, the liver, as in other studies, 2,12,13 was extensively analyzed and a variety of lesions that merited further investigation were found. Chronic liver disease of unknown cause is a common ailment in dolphins and is clinically characterized by wasting but is rarely characterized by jaundice. Hepatic lesions consist of hepatocyte degeneration, fatty change, and fibrosis. 33 Chronic liver disease is generally regarded as being nutritional in origin, but there is no definite evidence to support this. 19,33 Different types of acute hepatitis associated with nutritional or environmental toxins and biologic agents, such as viruses, bacteria, fungi, and parasites, have also been reported in stranded dolphins. 30 Parasitic infections have been recognized amongst the pathologic changes found in marine mammals. 34 Campula spp. is a common trematode that primarily inhabits the bile and pancreatic ducts, stomach, and intestine of cetaceans. 36 Affected ducts are dilated, fibrosed, and infiltrated with mononuclear cells, and the epithelium is hyperplastic. 8,27 Dolphins, as other cetaceans, are at the top of the marine food chain, and they accumulate pollutants in their tissues during their life. Therefore, this species is an excellent bioindicator to evaluate contamination of the marine environment. Numerous studies have been carried out to analyze concentrations of pollutants in dolphins from different areas of the world. 1,[4][5][6]16 Despite some studies that have described hepatic lesions in stranded dolphins, 2,9,12,22,29...

Veterinary Record (1998) 142, 248-249 MELANOMAS represent 6 to 15 per cent of skin tumours seen in the horse (Pulley and Stannard 1990). They are most common in ageing grey horses and result in multiple dermal tumours, primarily involving the ventral tail, perineum and external genitalia (Baker and Lehland 1975). They are described as slow growing, locally invasive masses, that usually do not metastasise (Pulley and Stannard 1990).Neoplasia causing neurological dysfunction has been reported as a rare occurrence in the horse (Traver and others 1977). Secondary neoplasms that cause spinal cord compression and ataxia in horses include lymphosarcoma, plasma cell myeloma, pheochromocytoma and fibrosarcoma (Schott and others 1990). This report relates a case of posterior paresis, bladder paralysis and perineal anaesthesia due to a metastatic melanoma at the lumbar level of the vertebral column of an aged grey Arabian horse.A 12-year-old female grey Arabian horse was observed in lateral recumbency with an acute onset of paralysis after a 10-day history of paresis affecting the pelvic limbs. The horse was capable of adopting sternal recumbency to eat and drink to maintain hydration but was anorectic. Other clinical signs included tachypnoea, hyperthermia, hyperaemia and oedema of the conjunctiva. Physical examination showed numerous black cutaneous nodules, 2 to 6 cm in diameter, on the ventral tail and surrounding the anus. It was reported that none of the masses had enlarged over the previous four years.Neurological examinations revealed paraparesis and paralysis of the pelvic limbs and tail. The pelvic limbs also showed hyporeflexia, hypotonia and depression of the superficial pain perception. Voluntary movement, muscle tone, spinal reflexes and cutaneous sensation were normal in the thoracic limbs. The animal also showed faecal and urinary incontinence, and decreased anal tone and anal sphincter reflexes. The rectum and colon were distended with faeces and the bladder was enlarged and was easily expressed manually. Two firm masses were detected at the lumbar region by rectal exploration. The nodules were large, unilobed, firmly adherent to the ventral surface of the lumbar vertebrae and slightly more pronounced to the left of the midline. Pulse strength was normal in the external iliac arteries. Due to the poor prognosis the horse was euthanased by an intravenous injection of sodium pentobarbitone followed by exsanguination.A microscopic examination of cerebrospinal fluid (CSF) taken immediately after euthanasia at the atlanto-occipital and lumbosacral levels did not reveal evidence of neoplastic cells. A full necropsy was performed and two pigmented black masses were found on the longitudinal section of the vertebral column in the ventral extradural space at the levels of the second and fourth lumbar vertebrae: their linear measurements were 12 cm and 15 cm, respectively. The masses infiltrated the musculature of the lumbar vertebral areas and the FIG 1: Longitudinal section at the lumbar level of the vertebral c...

Despite the good growth performance of several fish species when dietary fish oil is partly replaced by vegetable oils, recent studies have reported several types of intestinal morphological alterations in cultured fish fed high contents of vegetable lipid sources. However, the physiological process implied in these morphological changes have not been clarified yet, since alterations in the physiological mechanisms involved in the different processes of lipid absorption could be responsible for such gut morphological features. The objective of the present study was to investigate the activities of reacylation pathways in fish, the glycerol-3-phosphate and the monoacylglycerol pathways, in order to clarify the intestinal triacylglycerol (TAG) and phospholipid biosynthesis to better understand the morphological alterations observed in the intestine of fish fed vegetable oils. Intestinal microsomes of sea bream fed different lipid sources (fish, soyabean and rapeseed oils) at three different inclusion levels were isolated and incubated with L-[ 14 C(U)]glycerol-3-phosphate and [1-14 C]palmitoyl CoA. The results showed that in this fish species the glycerol-3-phosphate pathway is mainly involved in phospholipid synthesis, whereas TAG synthesis is mainly mediated by the monoacylglycerol pathway. Feeding with rapeseed oil reduced the reacylation activity in both pathways, explaining the high accumulation of lipid droplets in the supranuclear portion of the intestinal epithelium, whereas soyabean oil enhanced phosphatidylcholine synthesis, being associated with the increase in VLDL found in previous studies.

During an investigation into the microbiota of beaked whales (Mesoplodon bidens), nine isolates were obtained from different organs of four animals. The isolates were Gram-positive-staining, catalase-negative, short rod-shaped or coccoid organisms. A phylogenetic analysis based on 16S rRNA gene sequences of these isolates allocated them to the genus Weissella, showing 96.3 % and 96.0 % 16S rRNA gene sequence similarity with Weissella viridescens NRIC 1536 T and Weissella minor NRIC 1625 T , respectively. On the basis of phenotypic, physiological and phylogenetic evidence, it is proposed that the new isolates from whales represent a novel species of the genus Weissella, Weissella ceti sp. nov. The type strain of Weissella ceti is 1119-1A-09 T (5CECT 7719 T 5CCUG 59653 T ).Micro-organisms of the genus Weissella have been isolated from a wide variety of habitats such as soil, fresh vegetables and fermented foods or meat and meat products (Björkroth et al., 2002;Magnusson et al., 2002;De Bruyne et al., 2010;Padonou et al., 2010). In addition, some species have been isolated from human or animal sources. Thus, Weissella cibaria was isolated from human gall and faeces and Weissella confusa was isolated from faeces of children with bacteraemia (Green et al., 1990), from liver transplants (Green et al., 1991) and from the peritoneal fluid and abdominal wall of two patients (Riebel & Washington, 1990). In animals, W. confusa has been isolated from a primate (Cercopithecus mona) with a systemic infection (Vela et al., 2003b), from an autopsied dog and from the ear of a dog with otitis (Björkroth et al., 2002), and from intestines of farmed Asian seabass (Lates calcarifer) (Cai et al., 1998;Rengpipat et al., 2008). W. cibaria and Weissella hellenica have been isolated from the livers of canaries and from the ears of dogs with otitis and from the intestinal contents of flounder (Paralichthys olivaceus), respectively (Cai et al., 1998; Björkroth et al., 2002). Recently, members of the genus Weissella were isolated from diseased rainbow trout (Oncorhynchus mykiss) at a commercial fishery in China (Liu et al., 2009), although they were not identified to species level.Other species of the genus Weissella isolated from animals have not been formally described. In this article, we report the phenotypic and phylogenetic characterization of an unusual Weissella-like organism isolated from stranded beaked whales (Mesoplodon bidens).During an investigation into the microbiota of beaked whales, nine unidentified Gram-positive-staining, rodshaped or coccoid organisms were recovered from muscle tissue (strains 1119-2B-09, 1121-2A-09 and 1122-2A-09), brain (1120-7A-09), kidney (1119-4A-09 and 1121-4A-09), lymph nodes (1121-8A-09), spleen (1119-1A-09 T and 1121-1A-09) of four different animals. None of these animals showed organic lesions associated with these unidentified bacteria after post-mortem studies (gross and histological examination). Strains were isolated on Columbia blood agar plates (bioMérieux) incubated for 24 h at 37 u C...