Frecuencia de plasmocitomas extramedulares en caninos y felinos diagnosticados en el laboratorio de histopatología de la Universidad Nacional Mayor de San Marcos (periodo 2006-2016)

            The aim of this study was to determine the frequency of extramedullary plasmacytomas (EMPs) in canines and felines diagnosed in the Histopathology Laboratory of Universidad Nacional Mayor de San Marcos in the period 2006-2016. Records of histopathological diagnosis related to neoplasms were located (n=1758), of which 1703 corresponded to canines and 55 to felines. Of these, 110 (6.5%) and 8 (14.5%) were EMPs in canines and felines, respectively. The frequency of EMPs was determined with respect to the species (canine/feline), sex (male/female), age (<2, ˃2-˂7,> 7 for canines, and <1, ˃1-˂7, > 7 for cats) and breed. A frequency of EMPs of 6.5% was found in canines and 14.5% for felines in relation to the total neoplasms. Likewise, it occurred in 65 and 63% male canines and felines, respectively. Regarding age, the most affected age group in canines was >7 years, whereas in cats it appeared from one year of age. The highest frequency occurred in purebreds in canines (71%) and in mestizos in cats (88%).            El objetivo del presente estudio fue determinar la frecuencia de plasmocitomas extramedulares (PEMs) en caninos y felinos diagnosticados en el Laboratorio de Histopatología de Universidad Nacional Mayor de San Marcos en el periodo 2006-2016. Se ubicaron 1758 fichas de diagnóstico histopatológico relacionados a neoplasias, de las cuales 1703 correspondieron a caninos y 55 a felinos. De estos, 110 (6.5%) y 8 (14.5%) correspondieron a PEMs en caninos y felinos, respectivamente. Se determinó la frecuencia de PEMs con respecto a la especie (canino/felino), sexo (macho/hembra), edad (<2, ˃2-˂7, >7 para caninos, y <1, ˃1-˂7, >7 para felinos) y raza. Se encontró una frecuencia de PEMs de 6.5% en caninos y 14.5% en felinos con relación al total de neoplasias. Asimismo, se presentó en el 65 y 63% en caninos y felinos machos, respectivamente. Con relación a la edad, el grupo etario más afectado en caninos fue >7 años, en tanto que en felinos se presentó a partir del año de edad. La mayor frecuencia se presentó en razas definidas en caninos (71%) y en mestizos en felinos (88%)

Clasificación Histopatológica de Linfomas Caninos en la Casuística del Laboratorio de Patología Veterinaria de la Universidad Nacional Mayor de San Marcos (1996-2012)

The aim of this study was to apply the criteria of the World Health Organization (WHO) in the histopathological classification of canine lymphoma on cases diagnosed from 1996 to 2012 at the veterinary pathology laboratory of San Marcos University, Lima, Peru. A total of 1778 reports of canine neoplasia were revised and 16 cases with histopathological diagnoses of canine lymphoma were studied. The following types of lymphoma were identified: diffuse large B cell lymphoma (7/16) (immunoblastic subtype [4/16], centroblastic subtype [2/16], rich subtype T cells [1/16]), mantle cell lymphoma (3/ 16), peripheral T-cell lymphoma not otherwise specified (2/16), precursor B/T lymphoblastic lymphoma (2/16), anaplastic large cell lymphoma (1/16) and mycosis fungoides (1/16).El presente estudio tuvo como objetivo emplear los criterios de la Organización Mundial de la Salud (OMS) en la clasificación histopatológica del linfoma canino en los casos diagnosticados en el laboratorio de patología veterinaria de la Universidad Nacional Mayor de San Marcos, Lima, Perú, entre 1996 y 2012. Se revisaron 1778 informes con diagnóstico histopatológico de neoplasias caninas y se encontraron 16 casos con diagnóstico histopatológico de linfoma canino. Se identificaron los siguientes tipos de linfomas: Linfoma difuso de células grandes B (7/16) (subtipo inmunoblástico [4/16], subtipo centroblástico [2/16], subtipo rico en células T [1/16]), linfoma de células del manto (3/16), linfoma T periférico inespecífico (2/16), linfoma linfoblástico de células precursoras B/T (2/16), linfoma anaplásico de células grandes (1/16) y micosis fungoides (1/16)

A case of hydrometra in a crossbred bitch

El presente estudio reporta un caso de hidrometra en un canino hembra de 12 años que fue llevada a la Clínica de Animales Menores de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos (Lima, Perú). La perra presentaba signos clínicos de gestación aparente de 45 días, pero sin historia de celo o monta. Las constantes vitales, uroanálisis, hematología y bioquímica sanguínea indicaron valores dentro de los parámetros normales. En el examen ecográfico se observaron signos compatibles con hidrometra. Se llevó a cabo una ovariohisterectomía y se tomaron muestras uterinas para histopatología, lo cual confirmó el diagnóstico; además de una hiperplasia endometrial quística concomitante en uno de los cuernos uterinos.The present study reports a case of hydrometra in a female canine of 12 years who was taken to the Small Animals Clinic of the Faculty of Veterinary Medicine of the Universidad Nacional Mayor de San Marcos (Lima, Peru). The bitch had clinical signs of apparent gestation of 45 days, but no history of oestrus or mounts. Vital signs, uro-analysis, haematology, and blood biochemistry indicated values within normal parameters. The ultrasound examination showed compatible signs with hydrometra. An ovariohysterectomy was performed, and uterine samples were taken for histopathology, which confirmed the diagnosis, in addition to a concomitant cystic endometrial hyperplasia in one of the uterine horns

Demographic fitness of Belminus ferroae (Hemiptera: Triatominae) on three different hosts under laboratory conditions

Triatominae are widely recognised for their role as vectors of Trypanosoma cruzi. One of the main biological characteristics of this subfamily is their obligate haematophagous condition. However, previous studies on Belminus herreri and Belminus ferroae suggested that cockroaches are their principal hosts in domiciles. Due to this peculiar behaviour, the aim of this study was to analyse several demographic and reproductive parameters of B. ferroae fed on three different hosts (mice, cockroaches and Rhodnius prolixus) and relate B. ferroae fitness to these alternative hosts. The cohorts were reared under constant conditions. The egg hatching rate was similar for cohorts fed on cockroaches (69.4%) and R. prolixus (63.8%), but was much lower for the cohort fed on mice (16%). The development time from the nymph to adult stage and the average age of first reproduction (α) presented lower values in the cohort fed on cockroaches, which is consistent with the higher population growth rate associated with this host. Demographic parameters [intrinsic rate of natural increase, finite rate of population growth, net reproductive rate and damping ratio] showed statistically significant differences between the cohorts. Analysis of the life history of B. ferroae revealed a higher fitness related to the cockroach. The implications of these results for the origin of the subfamily are discussed.Centro de Estudios Parasitológicos y de Vectore

Demographic fitness of Belminus ferroae (Hemiptera: Triatominae) on three different hosts under laboratory conditions

Triatominae are widely recognised for their role as vectors of Trypanosoma cruzi. One of the main biological characteristics of this subfamily is their obligate haematophagous condition. However, previous studies on Belminus herreri and Belminus ferroae suggested that cockroaches are their principal hosts in domiciles. Due to this peculiar behaviour, the aim of this study was to analyse several demographic and reproductive parameters of B. ferroae fed on three different hosts (mice, cockroaches and Rhodnius prolixus) and relate B. ferroae fitness to these alternative hosts. The cohorts were reared under constant conditions. The egg hatching rate was similar for cohorts fed on cockroaches (69.4%) and R. prolixus (63.8%), but was much lower for the cohort fed on mice (16%). The development time from the nymph to adult stage and the average age of first reproduction (α) presented lower values in the cohort fed on cockroaches, which is consistent with the higher population growth rate associated with this host. Demographic parameters [intrinsic rate of natural increase, finite rate of population growth, net reproductive rate and damping ratio] showed statistically significant differences between the cohorts. Analysis of the life history of B. ferroae revealed a higher fitness related to the cockroach. The implications of these results for the origin of the subfamily are discussed.Centro de Estudios Parasitológicos y de Vectore

FRECUENCIA DE RABDOMIOSARCOMA CANINO EN EL LABORATORIO DE HISTOPATOLOGÍA VETERINARIA DE LA UNIVERSIDAD NACIONAL MAYOR DE SAN MARCOS (PERIODO 2000-2008)

The purpose of this study was to determine the frequency of canine rhabdomyosarcoma based on its histopathological classification, that were diagnosed in the histopathology laboratory of the Veterinary Faculty of San Marcos University, Lima, Peru in the period of January 2000 to December 2008. A total of 63 cases of canine rhabdomyosarcoma were diagnosed out of 1125 canine neoplasic tumors (5.6 ± 1.3%). Among this, only 47 cases were possible to classify where 27 cases (57.4%) corresponded to embryonal rhabdomyosarcoma, 19 (40.4%) to alveolar rhabdomyosarcoma, and one case (2.1%) to pleomorphic rhabdomyosarcoma. The most frequent region of the body affected by the embryonal type was the head and neck, where 6 to 10 year-old animals were the most affected.El objetivo del presente estudio fue determinar la frecuencia del rabdomiosarcoma canino, según su clasificación histopatológica, diagnosticado en el laboratorio de histopatología de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos, Lima, Perú, en el periodo de enero de 2000 a diciembre de 2008. Fueron diagnosticados 63 casos de rabdomiosarcoma canino dentro de un total de 1125 casos de neoplasias caninas (5.6 ± 1.3%). De estos, sólo 47 casos pudieron ser clasificados, donde 27 casos (57.4%) correspondieron a rabdomiosarcomas embrionarios, 19 (40.4%) a rabdomiosarcomas alveolares y un caso (2.1%) a rabdomiosarcoma pleomórfico. La región de mayor frecuencia de presentación para el tipo embrionario fue la cabeza y el cuello, siendo los canes de 6 a 10 años los más afectados

FREQUENCY OF HEPATIC LIPIDOSIS IN JUVENILE RAINBOW TROUT (ONCORHYNCHUS MYKISS) IN A FISH FARM IN THE PERUVIAN CENTRAL SIERRA

El objetivo del estudio fue determinar la frecuencia de lipidosis hepática en la trucha arcoíris (Oncorhynchus mykiss) de fase juvenil en base a lesiones anátomohistopatológicas en el hígado. Se trabajó con 58 peces de una piscigranja comercial de la sierra central del Perú. Los peces fueron clasificados como sanos (n=23) y enfermos (n=35) según el oscurecimiento de la piel y erosión de las aletas. Se colectaron muestras de hígado, que se fijaron en formol al 10% y fueron coloreadas con Hematoxilina-eosina. El 70.6% (41/58) de los peces presentó lesiones compatibles con lipidosis hepática, siendo el grado 3 el de mayor presentación (27.6%). Las mayores frecuencias de lipidosis hepática en grados 3 y 4 se observaron en animales sanos.The objective of the study was to determine the frequency of hepatic lipidosis in rainbow trout (Oncorhynchus mykiss) of juvenile phase based on anatomical and histopathological lesions in the liver. The specimens (n=58) were obtained from a commercial fish farm in the central highlands of Peru. The fish were classified as healthy (n=23) and ill (n=35) according to the darkening of the skin and fin erosion. Liver samples were collected, fixed in 10% formalin, and stained with hematoxylin eosin. Results showed that 70.6% (41/58) of the fish had lesions compatible with hepatic lipidosis, where grade 3 had the largest incidence (27.6%). The highest frequency of hepatic lipidosis in grade 3 and 4 was observed in healthy animals

Identificación inmunohistoquímica de antígenos receptores de angiotensina II en arteria umbilical de alpaca (Vicugna pacos)

The aim of this study was to identify the angiotensin II receptor antigens in the umbilical artery of the alpaca (Vicugna pacos). Six gravid uteri of alpacas from community farms located at 4000 m above the sea level in Cusco, Peru were used. The gestation time was estimated by the biparietal diameter of the foetus. Histological sections of 5 µm thickness were obtained from each umbilical artery. The Avidin-Biotin-peroxidase immunohistochemistry (IHQ) technique was applied, using IHQ reagents and polyclonal anti-Angiotensin II antibodies. The slides were analysed with a Leica DM750 binocular microscope with digital camera attached and LAS 4.7 Leica Macrosystems software. The intensity of marking was classified qualitatively (0: negative; 1: weak; 2: moderate; 3: strong labelling). For the positive control, ovine umbilical artery samples were used. The angiotensin II receptor antigens were in the smooth muscle cells of the umbilical arteries in the various gestation times. The antigens showed a strong labelling intensity, showing that angiotensin exerts its biological activity of vasoconstriction in the smooth muscle cells of the blood vessel.El objetivo de este trabajo fue identificar los antígenos receptores de angiotensina II en la arteria umbilical de la alpaca (Vicugna pacos). Se trabajó con seis úteros grávidos de alpacas procedentes de comunidades alpaqueras a 4000 msnm en Cusco, Perú, cuyo tiempo de gestación fue estimado por el diámetro biparietal del feto. Se obtuvieron cortes histológicos de 5 µm de espesor de cada arteria umbilical. Se aplicó la técnica de inmunohistoquímica (IHQ) Avidina-Biotina-peroxidasa, utilizando reactivos de IHQ y anticuerpos policlonales anti-Angiotensina II. Las láminas fueron analizadas con microscopio binocular Leica DM750 con cámara digital anexada y software LAS 4.7 Leica Macrosystems. La intensidad de marcación se clasificó de manera cualitativa (0: sin marcación; 1: marcación leve; 2: marcación moderada; 3: marcación fuerte). Para el control positivo se empleó muestras de arteria umbilical ovina. Los antígenos receptores de angiotensina II se localizaron en las células musculares lisas de las arterias umbilicales en los tiempos de gestación evaluados. Los antígenos presentaron una intensidad de marcación fuerte, lo que demuestra que la angiotensina ejerce su actividad biológica de vasoconstricción en las células musculares lisas del vaso sanguíneo

Frecuencia y carga parasitaria en branquias de alevinos de gamitana (Colossoma macropomum) mediante exámenes directos en tres establecimientos piscícolas de Ucayali, Perú

The aim of this study was to determine the frequency and load of ectoparasites in gills of cachama fry from three semi-intensive farming fish farms in the province of Coronel Portillo, Ucayali, Peru. Sixty fingerlings (35-45 days old) were selected from each of the three fingerling supply establishments (E1, E2 and E3), reared at similar density and feeding conditions. Three fresh gill layer sections were evaluated from both sides, by visual observation with a 2x magnifying glass to detect crustaceans and by direct microscopy at 10x for trematodes and at 40x for protozoa. Four degrees of infestation were considered; null (0 parasites), mild (1-3), moderate (4-7) and severe (>8). It was possible to identify mainly forms compatible with monogeneans of the Dactylogyridae family, compatible with Dactylogyrus spp (41.1%) and protozoa, mostly of the Oodiniaceae family, compatible with Piscinodinium spp (10.6%). No crustaceans were found. The frequencies of infestations were 28.3, 86.7 and 18.3% in E1, E2 and E3, respectively. Parasitic loads were mostly light (87.5, 53.8 and 83.3% for monogeneans and 80, 70 and 100% for protozoa, in E1, E2, and E3, respectively). The results suggest a lower sanitary condition in the E2 fingerlings. It is concluded that there was a higher frequency of infestations by monogeneans and light parasite loads in gills of cachama fry from the three fish farms evaluated by direct examinations.El objetivo del estudio fue determinar la frecuencia y carga de ectoparásitos en branquias de alevinos de gamitana procedentes de tres establecimientos piscícolas de crianza semi-intensiva en la provincia de Coronel Portillo, Ucayali, Perú. Se seleccionaron 60 alevinos (35-45 días de edad) por cada uno de los tres establecimientos proveedores de alevinos (E1, E2 y E3), criados a condiciones similares en densidad y alimentación. Se evaluaron tres secciones de capas branquiales de ambos lados en fresco, mediante observación visual con una lupa a 2x para detectar crustáceos y mediante microscopía directa a 10x para trematodos y a 40x para protozoarios. Se consideraron cuatro grados de infestación; nulo (0 parásitos), leves (1-3), moderado (4-7) y severo (>8). Se logró identificar principalmente formas compatibles con monogeneos de la familia Dactylogyridae, compatibles con Dactylogyrus spp (41.1%) y protozoarios, mayormente de la familia Oodiniaceae, compatibles con Piscinodinium spp (10.6%). No se encontraron crustáceos. Las frecuencias de infestaciones fueron de 28.3, 86.7 y 18.3% en E1, E2 y E3, respectivamente. Las cargas parasitarias fueron mayormente leves (87.5, 53.8 y 83.3% para monogeneos y 80, 70 y 100% para protozoarios, en E1, E2, y E3, respectivamente). Los resultados sugieren una menor condición sanitaria en los alevinos del E2. Se concluye que hubo mayor frecuencia de infestaciones por monogeneos y cargas parasitarias leves en branquias de alevinos de gamitanas de las tres piscigranjas evaluadas mediante exámenes directos

Pyometra and Sertoli cell tumor in a dog with persistent Müller duct

La persistencia del conducto de Müller (PMDS) es un tipo de seudohermafroditismo masculino hereditario que se ha registrado en varias razas de canes, donde los machos presentan testículos, cromosomas XY, además de oviducto, útero y vagina craneal como derivados de los ductos müllerianos. Se describe el caso de un canino Schnauzer fenotípicamente macho de 8 años de edad, con antecedentes de inapetencia, letargia y tenesmo desde los dos últimos días. La mascota presentaba órganos genitales masculinos pero evidenciaba criptorquidia lateral derecha. El examen ecográfico reveló esbozos del conducto de Muller (cuernos uterinos y cuerpo del útero) con un proceso infeccioso compatible con piometra. En el frotis sanguíneo se observaron células polimorfonucleares sin corpúsculos de Barr. Por otro lado, se encontró una masa tumoral craneal al cuerno uterino derecho correspondiendo a una neoplasia testicular de las células de Sertoli. El testículo izquierdo, ubicado en el saco escrotal estaba hipoplásico.Persistent Mullerian duct (PMDS) is a type of hereditary male pseudohermaphroditism observed in several dog breeds. Males have testes and XY chromosomes in addition to oviduct cranial vagina, uterus and bilateral Müllerian duct derivatives. In the present study is described the case of a 8-year Schnauzer dog, phenotypically male, with a history of anorexia, lethargy and tenesmus during the last two days. The pet had male genitalia but evident right lateral cryptorchidism; however, ultrasound examination revealed that the animal had remnants of the duct Muller (uterine body and horns) with an infectious process compatible with pyometra. The blood smear showed polymorphonuclear cells without corpuscles of Barr. A tumor mass was found cranial to the right uterine horn and corresponded to a testicular neoplasia of Sertoli cells. The left testicle was located in the scrotal sac and was hypoplastic