Comparison of gene expression in post-smolt Atlantic salmon challenged by LF-89-like and EM-90-like Piscirickettsia salmonis isolates reveals differences in the immune response associated with pathogenicity.

Piscirickettsiosis is the main bacterial disease affecting the Chilean salmon farming industry and is responsible for high economic losses. The aim of this study was to describe and comparatively quantify the immune response of post-smolt Atlantic salmon infected by cohabitation with fish bearing LF-89-like and EM-90-like Piscirickettsia salmonis. The expression of 17 genes related to the immune response was studied in head kidney from cohabitant fish by RT-qPCR. Our results at the transcriptomic level suggest that P. salmonis is able to manipulate the kinetics of cytokine production in a way that might constitute a virulence mechanism that promotes intracellular bacterial replication in cells of Atlantic salmon. This strategy involves the creation of an ideal environment for the microorganism based on induction of the inflammatory and IFN-mediated response, modulation of Th1 polarization, reduced antigen processing and presentation, modulation of the evasion of the immune response mediated by CD8+ T cells and promotion of the CD4+ T-cell response during the late stage of infection as a mechanism to escape host defences. This response was significantly exacerbated in fish infected by PS-EM-90 compared with fish infected by PS-LF-89, a finding that is probably associated with the higher pathogenicity of PS-EM-90.

Comparative pathogenesis of piscirickettsiosis in Atlantic salmon (Salmo salar L.) post-smolt experimentally challenged with LF-89-like and EM-90-like Piscirickettsia salmonis isolates.

Piscirickettsiosis (SRS) is the most prevalent bacterial disease in Chilean salmon aquaculture and is responsible for high economic losses. The aim of this study was to comparatively characterize the pathogenesis of SRS in post-smolt Atlantic salmon during the early and late stages of infection with Piscirickettsia salmonis LF-89-like (PS-LF-89) and EM-90-like (PS-EM-90) using a cohabitation challenge. The pathogenesis of cohabitant fish infected with the two isolates was relatively different due to cohabitant fish infected with PS-EM-90 showing higher cumulative mortality and shorter time until death compared with PS-LF-89 fish. PS-LF-89 caused an SRS infection characterized by kidney and liver lesions, whereas PS-EM-90 caused systemic and haemorrhagic disease characterized by kidney, liver, heart, brain, skeletal muscle and intestine lesions. Decreased serum concentration of total proteins and albumin as well as increased serum ALT, AST and creatinine levels in fish infected with both isolates confirmed that changes in liver and kidney function occurred during infection. Tissue damage, expressed as an SRS histoscore, showed a strong positive correlation with the bacterial load expressed as abundance of P. salmonis 16S rRNA transcripts in the livers and kidneys of fish affected with either isolate, but the correlation was significantly higher in fish infected with PS-EM-90. The results contribute to improving the understanding of the bacteria-host interaction.

Anatomical Variations of the Thoracic Duct: A Preliminary Report in Adult and Fetal Specimens.

The study aim is to evaluate anatomical variations of the thoracic duct using a specialized sequential injection procedure. The different types, frequencies, and anatomical topography were recorded and evaluated using 12 adult and 16 fetus specimens. By employing a perfusion pump device, cadavers were sequentially perfused with acrylic colored latex first through the internal marginal vein, then the thoracic duct at the interazygous-aortic recess, and finally through the posterior tibial artery. After perfusion, thoracic ducts were identified, partially dissected, and cadavers fixed by soaking in an aqueous solution of 5% formalin (v/v). Finally, further dissection and detailed photography were performed. Plexus shapes at different levels were clearly evident in 80% of the adult specimens. Whereas the presence of the cisterna chyli was detected in 100% of fetuses as an ampule dilatation at the beginning of the thoracic duct, in only one adult specimen was a dilatation found at the lumbar lymphatic trunk level. Functionally it is not known whether these modified anatomical features (plexus shapes) have served to compensate (as a derivative pathway) for lymphatic hypertension in life as a reflection of lymphatic system challenges and subsequent growth in the adult specimens.

[Obstetric hysterectomy in patients with accreta, increta and percreta placentae: comparison of two surgical techniques]. / Histerectomía obstétrica en pacientes con placenta acreta, increta y percreta: comparación de dos técnicas quirúrgicas.

OBJECTIVE: To analyze the maternal-fetal surgical complications techniques utilizing two obstetric hysterectomy in patients with placenta accreta, increta or percreta, in the Hospital General de Occidente, Jalisco, Mexico during the period 2011 to 2014. MATERIAL AND METHODS: observational, descriptive, cross-sectional study, analyzing maternal and fetal complications in all patients diagnosed with placenta accreta, increta or percreta, intervened with two surgical techniques obstetric hysterectomy, during the period January 2011 to December 2014, using clinical records to identify the study variables. The data were analyzed on Epi-Info 7 calculating frequencies, percentages, measures of central tendency and dispersion, also resorting to the use of a hypothesis test for mean difference bleeding. RESULTS: There were 71 obstetric hysterectomies, 47.88% were identified by placenta accreta, increta or percreta, of which 47.05% were operated with modified technique (group 1) and 52.95% with the conventional technique (group 2). The mean ages of the groups were 31.56 in group 1 and 29.44 in group 2. Statistically the bleeding with the modified surgical technique it is less than the bleeding conventional technique. CONCLUSIONS: The results serves two main purposes: to save the life of the patient and cause the least amount of side morbidity are placental problems, both the mother and the newborn, highlighting minor bleeding from a technique to another.

Piscirickettsiosis and Piscirickettsia salmonis in fish: a review.

The bacterium Piscirickettsia salmonis is the aetiological agent of piscirickettsiosis a severe disease that has caused major economic losses in the aquaculture industry since its appearance in 1989. Recent reports of P. salmonis or P. salmonis-like organisms in new fish hosts and geographical regions have increased interest in the bacterium. Because this gram-negative bacterium is still poorly understood, many relevant aspects of its life cycle, virulence and pathogenesis must be investigated before prophylactic procedures can be properly designed. The development of effective control strategies for the disease has been limited due to a lack of knowledge about the biology, intracellular growth, transmission and virulence of the organism. Piscirickettsiosis has been difficult to control; the failure of antibiotic treatment is common, and currently used vaccines show variable long-term efficacy. This review summarizes the biology and characteristics of the bacterium, including its virulence; the infective strategy of P. salmonis for survival and evasion of the host immune response; the host immune response to invasion by this pathogen; and newly described features of the pathology, pathogenesis, epidemiology and transmission. Current approaches to the prevention of and treatment for piscirickettsiosis are discussed.

Establishment and characterization of a new cell line (SSP-9) derived from Atlantic salmon Salmo salar that expresses type I ifn.

In the present work, the establishment and biological characterization of a new cell line, SSP-9, derived from the pronephros of the Atlantic salmon Salmo salar, are reported. These cells grew well in Leibovitz's (L15) medium supplemented with 10% foetal calf serum at temperatures from 15 to 25° C, and they have been sub-cultured over 100 passages to produce a continuous cell line with an epithelial-like morphology. The SSP-9 cells attached and spread efficiently at different plating densities, retaining 80% of cell viability after storage in liquid nitrogen. When karyotyped, the cells had 40-52 chromosomes, with a modal number of 48. Viral susceptibility tests showed that SSP-9 cells were susceptible to infectious pancreatic necrosis virus and infectious haematopoietic necrosis virus, producing infectious virus and regular cytopathic effects. Moreover, these cells could be stimulated by poly I:C, showing significant up-regulation in the expression of the genes that regulate immune responses, such as ifn and mx-1. SSP-9 cells constitutively express genes characteristic of macrophages, such as major histocompatibility complex (mhc-II) and interleukin 12b (il-12b), and flow cytometry assays confirmed that SSP-9 cells can be permanently transfected with plasmids expressing a reporter gene. Accordingly, this new cell line is apparently suitable for transgenic manipulation, and to study host cell-virus interactions and immune processes.

Neuropeptide Y mediates the short-term hypometabolic effect of estrogen deficiency in mice.

BACKGROUND: Estrogen deficiency increases body weight or total and central adiposity and decreases energy expenditure. Hypothalamic neuropeptide Y (NPY) expression is altered by estrogen deficiency in rodents, but the long-term consequences on energy homeostasis are unknown. OBJECTIVE: To investigate the role of NPY in the changes in energy expenditure and physical activity, as well as the associated changes in body weight and composition in response to short-term and long-term estrogen deficiency. DESIGN: Sham and ovariectomy (OVX) operations were performed at 8 weeks of age in wild-type (WT) and NPY(-/-) mice. Energy expenditure, physical activity, body composition and weight, as well as food intake were measured at 10-18 days (short-term) and 46-54 days (long-term) after OVX. RESULTS: OVX influences energy homeostasis differently at early compared with later time-points. At the early but not the late time point, OVX in WT mice reduced oxygen consumption and energy expenditure and tended to reduce resting metabolic rate. Interestingly, these effects of short-term estrogen deficiency were ablated by NPY deletion, with NPY(-/-) mice exhibiting significant increases in energy expenditure and resting metabolic rate. In addition to these hypermetabolic effects, OVX NPY(-/-) mice exhibited significantly lower body weight and whole-body fat mass relative to OVX WT controls at the short-term but not the long-term time point. Food intake and physical activity were unaltered by OVX, but NPY(-/-) mice exhibited significant reductions in these parameters relative to WT. CONCLUSION: The effects of estrogen deficiency to reduce energy metabolism are transient, and NPY is critical to this effect as well as the early OVX-induced obesity.

Tocilizumab treatment for nephrotic syndrome due to amyloidosis in Behcet's disease.

Renal involvement is an unusual but significant Behcet´s disease (BD) complication and AA amyloidosis appears to be the most common etiology. IL-6 is a pro-inflammatory cytokine with an important role in AA amyloidosis development. Tocilizumab (TCZ) is a humanized anti-IL-6 receptor antibody that has emerged as an effective and specific treatment in AA amyloidosis secondary to chronic inflammatory disorders. We report on a patient diagnosed with BD who developed nephrotic syndrome caused by renal AA amyloidosis with an excellent response to TCZ therapy.

Nephrotic syndrome and AA amyloidosis revealing adult-onset cryopyrin-associated periodic syndrome.

Cryopyrin-associated periodic syndrome (CAPS) is due to gain-of-function mutations in the cryopyrin gene, which determines an overactive inflammatory response. AA amyloidosis is a complication of this syndrome. A 53-year-old man was referred to us because of lower limb edema. Past history: at the age of 20, he complained of arthralgia/arthritis and bilateral hypoacusis. At the age of 35, he presented posterior uveitis, several episodes of conjunctivitis, and progressive loss of visual acuity. Laboratory tests disclosed nephrotic syndrome, and renal biopsy showed AA amyloidosis. He was given anakinra with improvement of arthritis. A genetic study revealed the p.D303N mutation in the cryopyrin gene, and he was diagnosed as having AA amyloidosis due to CAPS. Twenty-one months after starting anakinra, the arthritis has disappeared, although nephrotic-range proteinuria persisted. It is important to be aware of cryopyrin-associated periodic syndrome because it can cause irreversible complications, and there is effective therapy.

NPY modulates PYY function in the regulation of energy balance and glucose homeostasis.

AIMS: Both the neuronal-derived neuropeptide Y (NPY) and the gut hormone peptide YY (PYY) have been implicated in the regulation of energy balance and glucose homeostasis. However, despite similar affinities for the same Y receptors, the co-ordinated actions of these two peptides in energy and glucose homeostasis remain largely unknown. METHODS: To investigate the mechanisms and possible interactions between PYY with NPY in the regulation of these processes, we utilized NPY/PYY single and double mutant mouse models and examined parameters of energy balance and glucose homeostasis. RESULTS: PYY(-/-) mice exhibited increased fasting-induced food intake, enhanced fasting and oral glucose-induced serum insulin levels, and an impaired insulin tolerance, - changes not observed in NPY(-/-) mice. Interestingly, whereas PYY deficiency-induced impairment in insulin tolerance remained in NPY(-/-) PYY(-/-) mice, effects of PYY deficiency on fasting-induced food intake and serum insulin concentrations at baseline and after the oral glucose bolus were absent in NPY(-/-) PYY(-/-) mice, suggesting that NPY signalling may be required for PYY's action on insulin secretion and fasting-induced hyperphagia. Moreover, NPY(-/-) PYY(-/-) , but not NPY(-/-) or PYY(-/-) mice had significantly decreased daily food intake, indicating interactive control by NPY and PYY on spontaneous food intake. Furthermore, both NPY(-/-) and PYY(-/-) mice showed significantly reduced respiratory exchange ratio during the light phase, with no additive effects observed in NPY(-/-) PYY(-/-) mice, indicating that NPY and PYY may regulate oxidative fuel selection via partly shared mechanisms. Overall, physical activity and energy expenditure, however, are not significantly altered by NPY and PYY single or double deficiencies. CONCLUSIONS: These findings show significant and diverse interactions between NPY and PYY signalling in the regulation of different aspects of energy balance and glucose homeostasis.

Broth medium for the successful culture of the fish pathogen Piscirickettsia salmonis .

Piscirickettsiosis or salmonid rickettsial septicaemia (SRS) caused by Piscirickettsia salmonis constitutes one of the main problems in farmed salmonid and marine fishes. Since the first reports of the disease, it has been successfully isolated and maintained in eukaryotic cell--culture systems, but these systems are time-consuming, the media are costly, and eliminating heavily contaminated host cell debris is difficult. In this report, we describe a marine-based broth supplemented with L-cysteine, named AUSTRAL-SRS broth, that facilitates superior growth of P. salmonis strains. Strains reached an optical density of approximately 1.8 when absorbance was measured at 600 nm after 6 d incubation at 18°C. Several passages (n = 6) did not alter the culture kinetics. We report for the first time the purification of DNA, lipopolysaccharide (LPS) and whole membrane protein obtained from P. salmonis grown in this liquid medium, and thus provide a suitable platform to simplify the preparation of P. salmonis cells for genetic and serological studies. Moreover, the results of the cytopathic effect test showed that P. salmonis grown in AUSTRAL-SRS broth maintained their virulence properties, inducing apoptosis after 3 d. This makes the medium a good candidate for the successful growth of P. salmonis and an excellent basis for the development of low cost vaccines.

Synergistic effects of genetic beta cell dysfunction and maternal glucose intolerance on offspring metabolic phenotype in mice.

AIMS/HYPOTHESIS: Diabetes in pregnancy is linked to development of obesity in the offspring, but the mechanisms are not fully understood. Gestational diabetes mellitus (GDM) occurs when beta cells are unable to compensate for the normal insulin resistance of late pregnancy. In this study, we used a murine model of beta cell dysfunction to examine the effects of maternal GDM on phenotype in male offspring with and without an inherited predisposition for beta cell dysfunction. METHODS: Beta cell-specific aryl-hydrocarbon receptor nuclear translocator-null (ßArnt) mice develop GDM from beta cell dysfunction. ßArnt and control female mice were used to induce GDM and non-diabetic pregnancies, respectively. RESULTS: Offspring from GDM pregnancies became spontaneously obese on a normal-chow diet. They were heavier than offspring from non-diabetic pregnancies, with increased body fat. Respiratory exchange ratio (RER) was higher, indicating decreased capacity to switch to lipid oxidation. Metabolic rate in GDM offspring was decreased prior to onset of obesity. The phenotype was more pronounced in ßArnt GDM offspring than in GDM offspring of control genotype, demonstrating an interaction between genotype and pregnancy exposure. ßArnt GDM offspring had increased hypothalamic neuropeptide Y (Npy) and decreased pro-opiomelanocortin (Pomc) expression. Weight, body fat, insulin sensitivity and RER in all mice, and hypothalamic Npy in ßArnt mice were significantly correlated with AUC of maternal late pregnancy glucose tolerance tests (p < 0.01), but not with litter size, maternal weight, triacylglycerol or pre-pregnancy glycaemia. CONCLUSIONS/INTERPRETATION: In ßArnt mice, exposure to GDM and inheritance of genetic beta cell dysfunction had additive effects on male offspring obesity; severity of the offspring phenotype correlated with maternal glycaemia.

[Non compaction cardiomyopathy: a series of 15 cases]. / Miocardiopatía no compactada: una serie de 15 casos.

BACKGROUND: Non compaction cardiomyopathy is a rare disorder caused by the arrest of myocardial compaction during embryogenesis, leading to a non compacted endocardial layer with marked hypertrabeculation and deep recesses. AIM: To report the clinical and echocardiographic characteristics of a series of 15 adult patients with non-compaction cardiomyopathy. PATIENTS AND METHODS: We included a total of 15 patients aged 52 ± 17 years (40% males) diagnosed at our echocardiography laboratory between January 2001 and July 2010. RESULTS: The form of presentation was heart failure in 53% of subjects, syncope in 20%o, ventricular arrhythmias in 13%o and stroke in 7%>. Left ventricular end-diastolic diameter was 66 ± 11 mm and estimated ejection fraction was 27 ± 10%>. Apical and/or mid-ventricular segments of the left ventricle were involved in all the cases. Pulmonary hypertension was present in 40%o. The average follow-up was 19 months and no patient died during this period. Sixty seven percent of the patients had manifestations of heart failure, 27%o presented sustained ventricular arrhythmias and 20%> had atrial fibrillation or flutter, whereas 13%o had cerebral embolic events. An automated internal cardioverter defibrillator was implanted in 47%o of patients. CONCLUSIONS: Non-compaction cardiomyopathy is associated with high cardiovascular morbidity. The diagnosis is made in advanced stages of the disease, with significant dilation and ventricular dysfunction.

Peripheral neuropeptide Y Y1 receptors regulate lipid oxidation and fat accretion.

OBJECTIVE: Neuropeptide Y and its Y receptors are important players in the regulation of energy homeostasis. However, while their functions in feeding regulation are well recognized, functions in other critical aspects of energy homeostasis are largely unknown. To investigate the function of Y1 receptors in the regulation of energy homeostasis, we examined energy expenditure, physical activity, body composition, oxidative fuel selection and mitochondrial oxidative capacity in germline Y1(-/-) mice as well as in a conditional Y1-receptor-knockdown model in which Y1 receptors were knocked down in peripheral tissues of adult mice. RESULTS: Germline Y1(-/-) mice of both genders not only exhibit a decreased respiratory exchange ratio, indicative of increased lipid oxidation, but interestingly also develop late-onset obesity. However, the increased lipid oxidation is a primary effect of Y1 deletion rather than secondary to increased adiposity, as young Y1(-/-) mice are lean and show the same effect. The mechanism behind this is likely because of increased liver and muscle protein levels of carnitine palmitoyltransferase-1 (CPT-1) and maximal activity of key enzymes involved in beta-oxidation; beta-hydroxyacyl CoA dehydrogenase (betaHAD) and medium-chain acyl-CoA dehydrogenase (MCAD), leading to increased mitochondrial capacity for fatty acid transport and oxidation. These effects are controlled by peripheral Y1-receptor signalling, as adult-onset conditional Y1 knockdown in peripheral tissues also leads to increased lipid oxidation, liver CPT-1 levels and betaHAD activity. Importantly, these mice are resistant to diet-induced obesity. CONCLUSIONS: This work shows the primary function of peripheral Y1 receptors in the regulation of oxidative fuel selection and adiposity, opening up new avenues for anti-obesity treatments by targeting energy utilization in peripheral tissues rather than suppressing appetite by central effects.

Additive actions of the cannabinoid and neuropeptide Y systems on adiposity and lipid oxidation.

AIMS: Energy homeostasis is regulated by a complex interaction of molecules and pathways, and new antiobesity treatments are likely to require multiple pharmacological targeting of anorexigenic or orexigenic pathways to achieve effective loss of excess body weight and adiposity. Cannabinoids, acting via the cannabinoid-1 (CB1) receptor, and neuropeptide Y (NPY) are important modulators of feeding behaviour, energy metabolism and body composition. We investigated the interaction of CB1 and NPY in the regulation of energy homeostasis, hypothesizing that dual blockade of CB1 and NPY signalling will induce greater weight and/or fat loss than that induced by single blockade of either system alone. METHODS: We studied the effects of the CB1 antagonist Rimonabant on food intake, body weight, body composition, energy metabolism and bone physiology in wild-type (WT) and NPY knockout (NPY(-/-)) mice. Rimonabant was administered orally at 10 mg/kg body weight twice per day for 3 weeks. Oral Rimonabant was delivered voluntarily to mice via a novel method enabling studies to be carried out in the absence of gavage-induced stress. RESULTS: Mice with dual blockade of CB1 and NPY signalling (Rimonabant-treated NPY(-/-) mice) exhibited greater reductions in body weight and adiposity than mice with single blockade of either system alone (Rimonabant-treated WT or vehicle-treated NPY(-/-) mice). These changes occurred without loss of lean tissue mass or bone mass. Furthermore, Rimonabant-treated NPY(-/-) mice showed a lower respiratory exchange ratio than that seen in Rimonabant-treated WT or vehicle-treated NPY(-/-) mice, suggesting that this additive effect of dual blockade of CB1 and NPY involves promotion of lipid oxidation. On the other hand, energy expenditure and physical activity were comparable amongst all treatment groups. Interestingly, Rimonabant similarly and transiently reduced spontaneous and fasting-induced food intake in WT and NPY(-/-) mice in the first hour after administration only, suggesting independent regulation of feeding by CB1 and NPY signalling. In contrast, Rimonabant increased serum corticosterone levels in WT mice, but this effect was not seen in NPY(-/-) mice, indicating that NPY signalling may be required for effects of CB1 on the hypothalamo-pituitary-adrenal axis. CONCLUSIONS: Dual blockade of CB1 and NPY signalling leads to additive reductions in body weight and adiposity without concomitant loss of lean body mass or bone mass. An additive increase in lipid oxidation in dual CB1 and NPY blockade may contribute to the effect on adiposity. These findings open new avenues for more effective treatment of obesity via dual pharmacological manipulations of the CB1 and NPY systems.

Cryoglobulinemic glomerulonephritis in chronic hepatitis B infection.

Hepatitis B virus (HBV) infection is an uncommon cause of cryoglobulinemia. Renal cryoglobulinemia has been rarely reported in the setting of chronic hepatitis B infection. We describe a case of chronic hepatitis B infection with cryoglobulinemic glomerulonephritis (Gn) and provide information about the treatment and the evolution over a 30-month follow-up. A 41-year-old woman with chronic hepatitis B infection developed nephrotic syndrome and acute renal failure; other investigations revealed type 2 cryoglobulinemia; HBV DNA was detected in the cryoprecipitate. Renal biopsy showed findings of cryoglobulinemic Gn. She was given lamivudine, corticosteroids, plasma exchange, and mycophenolate mofetil. The renal function improved, nephrotic syndrome remitted, and HBV DNA became undetectable; there was no compromise of the liver function.

Obstructive nephropathy secondary to AA-type amyloidosis in ankylosing spondylitis.

AA-type amyloidosis of the genitourinary tract is a rare phenomenon and few cases are described in the literature. We report a 42-year-old man with ankylosing spondylitis, who developed hematuria, bilateral hydronephrosis, and renal failure caused by AA amyloidosis.

Remission of minimal change disease in Type 2 diabetes after streptococcus bacteremia.

A 41-year-old man with Type 2 diabetes developed sudden onset of nephrotic syndrome. He initially refused a renal biopsy. However, 3 months later, the nephrotic syndrome persisted and percutaneous renal biopsy was performed. The study with light microscopy, immunofluorescence and electron microscopy showed minimal change disease. Three weeks after biopsy, before immunosuppressive therapy was begun, the patient presented Group A Streptococcus (GAS) bacteremia and acute renal failure which needed hemodialysis. Afterwards, the renal function recovered and complete remission of the nephrotic syndrome, maintained during a 22-month follow-up, was observed. We discuss the possible mechanisms implicated in the remission. This report extends the spectrum of infections associated with remission of minimal change disease (MCD).

Severe renal complications in chronic myelomonocytic leukemia.

A 56-year-old man presented with peripheral monocytosis and massive nephrotic syndrome. He was diagnosed as having chronic myelomonocytic leukemia and membranous glomerulonephritis. He received prednisone, chlorambucil and hydroxyurea, but the nephrotic syndrome persisted. Seven months after diagnosis, he was started on cyclosporin A; 1 month later he developed acute renal failure due to radiolucent bilateral renoureteral stones. His kidney function recovered after placing ureteral catheters and urine alkalization. Afterward, he was given mycophenolate mofetil, and proteinuria decreased to subnephrotic levels (1 g/24 hours). This case highlights 2 severe renal complications in this type of leukemia. To the best of our knowledge, there are only 2 previous cases of glomerulonephritis, histologically proven, associated with chronic myelomonocytic leukemia. On the other hand, reversible acute renal failure due to radiolucent bilateral renoureteral stones has never been reported. Also, as far as we know, mycophenolate mofetil was successfully used here for the first time for treating glomerulonephritis-related chronic myelomonocytic leukemia.

[Chile's experience with developing abalone (Haliotis spp.) farming: opportunities and challenges]. / La experiencia del desarrollo del cultivo de abal6ón (Haliotis spp.) en Chile: oportunidades y desafíos.

Intensive abalone farming--specifically of the red abalone (Haliotis rufescens) and the green (or Japanese) abalone (Haliotis discus hannai)--has expanded rapidly in Chile since the late 1990s, and this article presents an overview of the challenges facing the industry and the factors which favour its development. At present, 100% of Chile's abalone enterprises farm the H. rufescens species, owing to its suitability for full-cycle culture. In the analysis of factors that facilitate the development of abalone farming in Chile, those that stand out include the characteristics of the aquatic ecosystem, existing entrepreneurial and professional skills, decisive government support in co-financing scientific and technological projects, infrastructure and associated services to support these development initiatives and a market where prices have remained stable and demand for abalone products has been steady. The greatest challenges facing intensive abalone farming in Chile are providing a constant supply of macroalgae for abalone feed and developing complementary feed, as well as updating current legislation on intensive abalone farming, strengthening producer associations and establishing health certification. The article discusses examples of the impact that native organisms can have on animals introduced into an aquatic ecosystem and the international transmission of agents such as withering syndrome and sabellid polychaete infestation disease, associated with the movement of abalone seeds and broodstock. The article also emphasises the importance of implementing the recommendations of the World Organisation for Animal Health.