PRIMARY CILIARY DYSKINESIA IN OES

Primary Ciliary Dyskinesia (PCD) in Old English Sheepdogs

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F. Billen¹, AC. Merveille¹, D. Binst², V. Geyskens², AS. Lequarré¹,
M. Jaspers³, M. Jorissen³, D. Peeters¹, M. Georges¹, C. Clercx¹.

1 Faculty of Veterinary Medicine, University of Liège, Belgium.
2 Faculty of Veterinary Medicine, University of Gent, Belgium.
3 Laboratory of experimental Otorhinolaryngology, University of Leuven, Belgium.

Introduction: Primary ciliary dyskinesia (PCD), previously called immotile cilia syndrome (ICS), is a divers group of inherited structural and functional abnormalities affecting the cilia of the respiratory tract mucosa and other organs which results mainly in recurrent respiratory tract infections. In dogs, PCD is a rare disease but reported in more than 19 breeds, including Old English sheepdogs. The lack of coordination and ineffectiveness of the ciliary function result in a slow clearance of mucus from the airways; this in turn results in chronic mucus plugging and inflammation of nasal cavities, trachea and lower airways. As a consequence, clinical signs will include chronic respiratory abnormalities such as rhinosinusitis, bronchitis, bronchopneumonia and bronchiectasis (i.e dilation of bronchi secondary to chronic inflammation). These symptoms (sneezing, bilateral sero-mucous nasal discharge, productive cough, exercise intolerance, dyspnoea, and lethargy) commonly appear at a very early age
(i.e. weeks to months). Although the respiratory system signs are usually the most important, several signs related to pathology in other tissues with ciliated epithelia or microtubules can occur, such as otitis media, infertility in males and females, hydrocephalus, and renal fibrosis or dilation of renal tubules. Some dogs with PCD may present the "Kartagener's syndrome" which represents a triad of signs that includes bronchectasis, complete transposition of viscera (situs inversus) and chronic rhinosinusitis. While PCD may be suspected based on history, clinical signs, diagnostic imaging and endoscopy, final diagnosis requires the observation of ciliary structure abnormalities after ciliogenesis (i.e. culture of ciliated cells) of biopsies of ciliated epithelium (i.e. the nasal, tracheal or bronchial mucosa) with the use of transmission electron microscopy.

The ciliated respiratory mucosa.

A. Microscopic view of the respiratory mucosa consisting of ciliated epithelial cells (i.e. presence of cilia at their apical surface). 
B. Focus on the apical surface of the ciliated epithelial cell. 
C. Inner structure of the transverse section of a cilium.

Electron micrographs of transverse sections of canine respiratory cilia.

a. Normal ciliary axoneme with one central pair of microtubules (arrow) and nine peripheral microtubular doublets (arrow head).
b. Ciliary axoneme from a dog with PCD with central pair abnormalities. The central pair of microtubules is eccentric located (arrow) and one of the peripheral doublet is centrally displaced (arrow head)

Even though PCD is not a curable disorder, it can frequently be managed for some years. A key element in this successful management is the adequate monitoring of infecting microorganisms and judicious use of antibiotics over time. The long-term prognosis is poor, since even in case of adequate management, the disease generally progresses over time and the response to treatment becomes poorer. It would be very useful to have a genetic test able to identify carriers and exclude them from breeding programmes.

History in Old English sheepdogs: Four Old English Sheepdog puppies (8-15 months old), belonging to two different but related litters, were referred to the small animal clinic of the Veterinary Faculty of the University of Liège. All dogs presented, since several months, recurrent chronic mucoid to muco-purulent nasal discharge, moist productive cough with episodes of dyspnoea, hyperthermia and anorexia, resolving only transiently with various treatments (antibiotics, mucolytics, nebulization). Thoracic radiographs showed severe bronchopneumonia with bronchiectasis in the cranial lung lobes. In one dog, thoracic radiographs showed situs inversus of the viscera (i.e. the cardiac silhouette and the stomach were in dextroposition) indicating Kartagener's syndrome. Endoscopy revealed inflamed mucosa, moderate to large amounts of mucopurulent secretions along all the upper and lower airway tracts. Analysis of these secretions (with a broncho¬alveolar lavage) was compatible with acute bronchopneumonia. Transmission electron microscopy analysis of sampled ciliated cells and of ciliated cells after ciliogenesis confirmed the diagnosis of primary ciliary dyskinesia.

Litter history and pedigree analysis: Pedigree analysis of the two affected litters indicated that the sire of the first litter was the grandsire of the second litter. Further breeders information and pedigree examination revealed finally six affected related litters. Initial pedigree analysis was compatible with a monogenic autosomal recessive pattern of inheritance of a genetic defect. A genetic defect is a mistake in a gene called a mutation. There are basically two kinds of mutations, dominant and recessive. Every cell in the body (except sperm and eggs) has two copies of each gene (one from the sire, and one from the dam). A dominant mutation is where one defective copy of a gene is enough to affect the individual, whereas a recessive mutation requires that both copies of the gene carry a mutation for the individual to be affected. In other words, if the dog is only carrier, i.e he has only one defective copy of a gene, he will be clinically healthy. Here the disease is recessive, in consequence, in theory, if both parents are carriers, 25% of the puppies will be healthy, 50% of the puppies will be carriers and 25% of the puppies will be affected. If only one of the parents is carrier, 50% of the puppies will be carriers. In other words, to get affected puppies both parents need to be at least carriers.

Genetic analysis: Based on this preliminary information, blood was drawn from about twenty Old English sheepdogs (5 affected and 15 clinically healthy dogs) for genetic testing. All dogs underwent also a complete physical examination. DNA was extracted from the blood and analyzed in the Department of Genetics at the Faculty of Veterinary Medicine of the University of Liège with the European project on canine genetics "LUPA".

The first aim of these genetic analyses was to confirm the pattern of inheritance of the disease. First genetic analyses were able to differentiate healthy, carrier and affected dogs with a good accuracy and confirmed the monogenic autosomal recessive pattern of inheritance. These first results clearly show the existence of a large number of carriers that are clinically healthy and used for breeding. In consequence, a large number of carriers and affected dogs must be present in the Old English sheepdogs' population.

Pedigree associated with results of genetic analyses of affected and clinically healthy Old English sheepdogs.

The second aim of these genetic analyses was to identify the genetic mutation in order to set up a genetic test able to identify healthy, carriers and affected dogs with 100% accuracy. At the moment, the region of the genome containing the genetic mutation has been identified. Unfortunately, the identified region of the affected chromosome still contains a huge amount of genes (about 150 genes) and their complete analysis would take a lot of time and cost a lot of money.

In conclusion, we need to study more affected puppies to have a better idea of the incidence of the disease within the Old English sheepdog population and to be able to identify the responsible gene of the disease.

So if you hear about any affected puppies, please contact us as soon as possible

For the clinical aspect:
Dr F. Billen
+32(0)43664200
fbillen@ulg.ac.be

For the genetic part:
Dr A-C. Merveille
+32(0)43664200
acmerveille@ulg.ac.be

You may also visit the LUPA website :www.eurolupa.org

LA DISQUINESIA CILIAR PRIMARIA EN EL BOBTAIL

La Disquinesia Ciliar conduce a problemas respiratorios. Alrededor del 17% de los Viejos Pastores Ingleses (Bobtail)  son portadores de la mutación genética responsable de esta enfermedad. Una prueba ADN fiable pemitirá de despistar los reproductores, adaptar los aparejamientos para evitar hacer nacer cachorros afectados y de propagar la enfermedad dentro de la raza.

Una enfermedad grave hereditaria

La Disquinesia Ciliar conduce a problemas respiratorios crónicos. Los primeros síntomas se asocian de los primeros días de nacimiento a través de infecciones de la mucosa respiratoria (nariz, traquea, bronquios) que se traducen en estornudos, tos grasa y bronquitis crónicas. Mismo si la enfermedad es tratada precozmente, los síntomas se amplifican y el perro es generalmente eutonasiado.  

Una enfermedad frecuente

Alrededor del 17% de los Bobtail en Europa son portadores de la mutación genética responsable de la Disquinesia Ciliar. Un Criador puede aparejar sin saberlo un macho reproductor portador y una hembra portadora y engendrar una camada de cachorros afectados.

Un perro reproductor que es portador sano, no desarrolla la enfermedad pero la transmite al 50% de su descendencia. Un reproductor portador de la mutación y que reproduce mucho, propaga la enfermedad en el seno de la raza y contribuye a aumentar la frecuencia de la mutación y a multiplicar el número de cachorros afectados.

Una enfermedad posible de evitar

Cuando un perro está afectado por la enfermedad, ésto significa que sus dos padres son portadores sanos (los perros afectados no son fértiles). El criador no sensibilizado con la Disquinesia Ciliar puede acoplar sin saberlo los reproductores portadores de la mutación y hacer nacer cachorros afectados.

Una prueba ADN, llamada test PCD (Disquinesia Ciliar Primaria (DCP), permite despistar la Disquinesia del Bobtail con una fiabilidad superior al 99%.

Evitar de hacer nacer cachorros afectados

Para segurizar su criadero y no correr riesgos de hacer nacer cachorros afectados, el criador debe testar absolutamente sus reproductores con la ayuda de una prueba ADN.

Tras la acquisición de un cachorro para la reproducción o tras la utilización de un reproductor para un aparejamiento, el criador verifica el estatu genético del perro en relación a la Disquinesia solicitando una prueba ADN.

Una prueba ADN fácil de realizar

El veterinario realiza una muestra con un frotis bucal que será enviado al laboratorio. El resultado, que se envía en varios días, indica si el animal es sano, portador sano o afectado de Disquinesia Ciliar. El resultado se envía en forma de certificado genético, y puede ser utilizado como garantía dentro del marco de una reproducción o para justificar la venta de cachorros exentos de Disquinesia.

El veterinario que observa prematuramente problemas respiratorios en un joven Bobtail puede a través de una prueba ADN confirmar o desmentir el diagnóstico de la Disquinesia Ciliar. Si el perro está efectivamente afectados, los padres deberán ser testados igualmente.

El criador que conoce el estatu genético de sus perros puede adaptar sus apareajamientos, evitar de hacer nacer cachorros  afectados y limitar la propagación de la Disquinesia dentro de esta raza.

Dr Guillaume QUENEY

Laboratorio ANTAGENE

CEPILLADO PARA SHOWS

EL PENTOSAN POLISULFATO PARA LA ARTROSIS.... CUIDADO!

Tratamiento de la osteoartrosis en pequeños animales

La osteoartrosis es una patología articular de condición crónica y progresiva que afecta tanto a tejidos blandos como a estructuras óseas. Se calcula que un 20% de la población canina adulta y un 20% de los gatos de edad superior a 12 años sufren esta dolencia

Los problemas articulares de los animales de compañía se dividen tradicionalmente en dos grandes grupos:

1. enfermedades inflamatorias propiamente dichas, entre las que destacan por un lado patologías de etiología infecciosa y por otro trastornos inmunomediados (p. ej. lupus o artritis reumatoidea).
2. procesos articulares de tipo degenerativo más frecuentemente conocidos como osteoartrosis (OA).

En la OA la inflamación suele estar presente pero no es el fenómeno principal y la enfermedad tiende a presentarse en episodios en los que alternan ciclos de remisión y agravamiento del trastorno articular.

En la osteoartrosis la inflamación suele estar presente pero no es el fenómeno principal y la enfermedad tiende a presentarse en episodios en los que alternan ciclos de remisión y agravamiento del trastorno articular.

En los humanos se acepta la OA como una de las causas más importantes de pérdida de productividad laboral. Puesto que esta patología es considerada para muchos una alteración ligada, por un lado al envejecimiento natural de los individuos y por otro lado a los de mayor peso dentro de una especie, es fácil concluir que dentro de los animales de compañía los caninos geriatras y de grandes razas como Mastín, San Bernardo, Dogo, pastores, etc. padecerán de forma más acusada este tipo de trastornos.

La OA es una patología articular crónica y progresiva que afecta tanto a tejidos blandos como a estructuras óseas, en la que el cartílago articular se degrada lentamente y el hueso subcondral reacciona produciendo osteofitos, resultando un estrechamiento del espacio articular y una restricción del rango de movimientos acompañado de dolor e inflamación

ratamiento de la osteoartrosis

La OA continúa siendo una patología en la que se pretende hacer un control de la progresión más que lograr una curación absoluta. Bajo estas condiciones es indudable que un diagnóstico correcto, pero sobre todo precoz, va a permitir al veterinario clínico un margen de actuación con el que se consiga hacer un control de la progresión de la enfermedad razonable, aunque para ello siempre sea necesario contar con la colaboración de los propietarios.

Para realizar una clasificación de los posibles tratamientos de la OA podremos hacer algunos grandes grupos como:

1. Farmacológico: agentes antiinflamatorios, agentes modificadores de la enfermedad más comúnmente conocidos como condroprotectores y otros fármacos en fase de experimentación.
2. Dietético.
3. Fisioterapia y terapias alternativas.
4. Quirúrgico.

Tratamiento farmacológico

Medicamentos antiinflamatorios

Desde el descubrimiento del ácido acetilsalicílico y sus propiedades analgésicas hace ya más de un siglo, se han sucedido una importante lista de AINE como tratamiento de la osteoartritis. Este grupo de agentes actúa principalmente reduciendo la cantidad de prostaglandinas inflamato inflamatorias, particularmente la PGE2 a través de la inhibición de las enzimas de la ciclooxigenasa. Esto da lugar a un descenso de la vasodilatación, edema y permeabilidad vascular así como a un aumento del umbral del dolor. Otros efectos beneficiosos tales como la inhibición de la producción de radicales libres, estabilización de membranas de los lisosomas y una disminución de la actividad de los neutrófilos también pueden ser posibles.

Los efectos colaterales no deseados de los AINE incluyen tendencia a causar ulceración gastrointestinal, necrosis renal y disfunción plaquetaria. Existen investigaciones que prueban que algunos AINE pueden afectar al metabolismo del condrocito y disminuir la síntesis de glicosaminoglicanos.

Recientemente se ha descubierto la existencia de dos tipos de ciclooxigenasa:

COX-1 y COX-2. La COX-1 parece ser una forma endógena responsable de la producción de prostaglandinas que ayudan a mantener la integridad de la mucosa gástrica y el endotelio vascular, mientras que la COX-2 se produce como parte de la respuesta inflamatoria y es responsable de producir prostagladinas de acción inflamatoria. Este hecho determina la elección de un determinado tipo de fármacos con mayor efecto inhibidor de COX-2 y menores efectos secundarios a largo plazo, en el manejo de la enfermedad inflamatoria crónica.

En cuanto al uso de corticoides tiende a desaparecer por sus importantes efectos secundarios.

Agentes modificadores de la enfermedad osteoartrósica

Entre estas sustancias, también conocidas como DMOAD (Disease Modifying Osteoarthritis Drugs) o condroprotectores, destacan dos: condroitín sulfato y glucosamina. Su extracción y purificación es a partir de tejidos animales. Concretamente el condroitín sulfato se extrae a partir del cartílago y la glucosamina del exoesqueleto de crustáceos. Estos medicamentos son los de uso más frecuente en la clínica ya sean de forma aislada o asociados.

Su utilización en el tratamiento de la OA veterinaria es relativamente reciente. Aunque el mecanismo de acción de estas nuevas sustancias no está completamente aclarado, las hipótesis propuestas se basan en un efecto positivo en la síntesis de cartílago al proporcionar al condrocito glicosaminoglicanos en cantidades importantes favoreciendo de esta forma la producción de matriz extracelular, así como un efecto inhibidor de los enzimas degradativos encontrados en la OA, fundamentalmente metaloproteasas (figura 8). Otra importante ventaja que ofrecen estos medicamentos es su facilidad de administración vía oral y los escasos efectos secundarios que se han descrito.

La osteoartrosis continúa siendo una patología en la que se pretende hacer un control de la progresión más que lograr una curación absoluta.

Otro medicamento con efecto antiartrósico demostrado es el polisulfato de pentosan, extraído de una hemicelulosa de haya. Es muy popular, sobre todo en Australia desde que en 1986 se aprobó su uso, y cuenta con una buena aceptación entre los clínicos veterinarios de ese país, pero todavía no está comercializado en España.

La dosis recomendada es de 3 mg/kg vía subcutánea una vez por semana. Su principal mecanismo de acción parece ser preservar el contenido de proteoglicanos, estimulando la síntesis de ácido hialurónico por los fibroblastos sinoviales.

Otros como el ácido hialurónico se utilizan en medicina equina mediante inyección intraarticular, pero no existe experiencia de su uso en caninos.

Otros fármacos

La diacereína ha sido aprobada en varios países para su uso en el tratamiento de la OA de humanos. Esta sustancia, extraída de las plantas de aloe, actúa como inhibidor de la interleuquina-1 y podría ser la primera droga anticitoquina disponible en el mercado veterinario. En modelos animales osteoartrósicos, este medicamento ha sido efectivo cuando se aplica a dosis altas.

La doxiciclina es un antibiótico que inhibe la actividad de las metaloproteasas in vitro. En estudios experimentales con animales tratados previamente con doxiciclina, las actividades colagenolíticas y gelatinolíticas de los cartílagos articulares fueron 4 o 5 veces mayores que en los no tratados.

Niacinamida (forma de vitamina B3), ácidos grasos Omega-3 y linimentos transcutáneos a base de capsaicina son medicamentos estudiados en su aplicación para el tratamiento de la OA.

Control dietético

A pesar de que la reducción de peso ha sido bastante ignorada, tanto como objeto de investigación como desde el punto de vista del veterinario clínico en el tratamiento de la OA, probablemente sea uno de los componentes más eficaces para el buen manejo de esta patología. Desafortunadamente los propietarios, en muchas ocasiones, no son conscientes de los efectos que el sobrepeso puede ejercer en la evolución de la OA. La pérdida de peso debería ser cuidadosamente valorada y planeada en todos los pacientes con OA, con el fin de limitar el esfuerzo necesario en la locomoción y, de esa forma, limitar también las fuerzas ejercidas sobre las articulaciones. La sobrecarga que sufren los cartílagos de un animal obeso sería un proceso comparable con la aceleración de la OA que en muchos casos se presenta, por ejemplo, en un animal con una cadera displásica que sufre una lesión en un miembro anterior y necesita desviar su centro de gravedad, durante la locomoción, hacia sus extremidades posteriores. Sin duda a partir de ese momento esa cadera displásica y en ocasiones asintomática sufre una mayor “carga física”, acelerándose el proceso degenerativo articular y la presentación de sintomatología.

Fisioterapia y terapias alternativas

• Los protocolos de fisioterapia desempeñarán probablemente en el futuro, al igual que ocurre en humana, un papel muy importante tanto para el tratamiento de patologías musculoesqueléticas y neurológicas crónicas como para la recuperación posquirúrgica de algunos casos. Existen ya a nivel mundial profesionales fisioterapeutas y centros especializados donde se prestan estos servicios desde hace tiempo aunque, en España, el autor no tiene constancia de su existencia.

• El ejercicio físico es otro de los factores que pueden ser útiles para la OA. La actividad debe ser calculada en articulaciones osteoartríticas, para poder crear un equilibrio entre el total desuso y los efectos destructores al forzar de forma severa y repetida el movimiento articular. De manera general, el ejercicio leve o moderado mediante actividad aeróbica (paseos lentos, natación, etc.) ayudan a mejorar la sintomatología del paciente.

• En cuanto a la magnetoterapia, en teoría, los campos magnéticos tienen efecto sobre los cartílagos mediante flujos de potenciales, en los cuales, los iones móviles en el interior de la matriz extracelular sobrepasan a las cargas negativas fijas en el proteoglicano sulfatado que se generan en respuesta a la compresión y deformación de los cartílagos. Los campos magnéticos bajos en energía han sido capaces de estimular el metabolismo del cartílago articular in vitro.

Existe una unidad de terapia para la aplicación de campos electromagnéticos pulsados para veterinaria (PSTVE, Pulsed Signal Technology- Biomagnetic Therapy Systems, Boca Raton, Florida) comercializada en Estados Unidos. Pruebas que se están llevando a cabo actualmente con dicha unidad han mostrados resultados prometedores.

Otros tratamientos clasificados como alternativos es posible que sean más considerados dentro de la medicina veterinaria en el futuro, incluyendo la acupuntura, moxibustión, masoterapia, laserterapia y electroestimulación.

Tratamientos quirúrgicos

Los tratamientos quirúrgicos incluyen técnicas de artroplastia, artrodesis y sustitución articular completa (prótesis) (figura 9).

Otros tratamientos quirúrgicos en fase de investigación son la reparación quirúrgica completa con técnicas de transplantes mediante autoinjerto de periostio, pericondrio, cultivos de condrocitos y stem cells mesenquimales.

Los protocolos de fisioterapia desempeñarán probablemente en el futuro, al igual que ocurre en humana, un papel muy importante tanto para el tratamiento de patologías musculoesqueléticas y neurológicas crónicas como para la recuperación posquirúrgica de algunos casos.

MI EXPERIENCIA CON UNO DE ESTOS FÁRMACOS -

Recientemente se lanzó en el mercado de mi país el polisulfato de pentosan ( Artrosan del laboratorio Köning) con muy buenas referencias.

Lo comencé a usar luego de consultar a mi veterinaria de confianza mayormente en mis perros adultos mayores y luego en los más jóvenes. En 3 semanas de tratamiento, es una inyección subcutánea por semana durante 1 mes, se observó buena mejoría de los más afectados por la OA que son los mayores.

Lamentablemente con los más jóvenes, especialmente con una hembra de 5 años, mi experiencia fue desastrosa. Sólo se le administró una dosis y a los 4 días sufrió una hemorragia masiva que diezmó su vida. La explicación del laboratorio fue que en el 1% de los casos sucede esto. 

Indudablemente pensamos con mi veterinaria que había alguna coagulopatía silente de base o alguna afección hepática que no dio síntomas antes. 

De todas formas si bien es una excelente droga, es de manejarla con cuidado. Lo que noté es que a todos los que le administré el Artrosan ( el cual suspendí luego de esta experiencia) presentan ahora una gastritis, en algunos casos severa. 

POR FAVOR, a quien le esté adminisitrando pentosan polisulfato, SIEMPRE consultar antes y chequear al perro o gato en cuanto a su estado de salud. NO ADMINISTRAR si existe gastritis previa, coagulopatía o desórdenes hepáticos. Vale más la vida de tu perro que sus articulaciones. Y siempre hay otras opciones terapéuticas. 

En mi caso... perdí a mi más amada perra... crío Bobtails hace 30 años, y cada tanto uno tiene esos ejemplares especiales que son como la luz de nuestros ojos, una extensión de nuestra Alma... la perdí para siempre, por una inyección... por eso comparto esta experiencia...porque realmente el riesgo/beneficio hay que tenerlo en cuenta.

CEREBELLAR ABIOTROPHY IN THE OLD ENGLISH SHEEPDOG: Its cause and diagnosis

Jerold S Bell DVM, Tufts University School of Veterinary Medicine

To understand the diagnosis of cerebellar abiotrophy (CA) in the Old English Sheepdog, you must understand the condition. CA causes a progressive loss of muscular coordination. It is not a painful condition, does not cause muscular weakness, and does not affect the mind of the dog. CA is a simple autosomal recessive genetic disorder. This means that for a dog to be affected, both parents have to be a carrier of the defective gene. Carriers do not show signs of the condition, and do not differ from other normal dogs except for their ability to pass the defective gene to approximately half of their offspring.

The cerebellum controls muscular coordination in the body. CA causes a specific cell, called a Purkinje cell to die off in the cerebellum. The Purkinje cell acts as a connector between several other cells in the cerebellum to control a process called proprioception. This process allows the mind to recognize where your limbs and body are “in space.” Because of this process, you can close your eyes and touch your nose, because you “know” where your nose and hand are. This process is progressively lost in CA.

CA manifests itself as an over and under modulation in muscle activity. Affected dogs cannot smoothly control the rate, force, and range of their movements. This can cause an over-reaching and high stepping gait. When going up and down stairs, they can float their front legs out, because they don’t know where their leg is in relationship to the stair. This is a very specific movement for CA. It has caused some owners to question whether their dog may have a problem with vision, which is normal. Affected dogs also often stumble or miss a step with their hind paws.

There can also be abnormal body movements of the trunk, with swaying of the pelvic limbs, and a characteristic bounce of the hind end. There can also be a mild disturbance of balance in CA, where affected dogs can fall over, but then get right up. All four limbs are affected with CA. The severity of clinical signs is symmetrical between the left and right sides of the body, although the forelimbs or hindlimbs may be more significantly affected.

There is a great range of severity of affected Old English Sheepdogs. Some can progress in their severity to the point that they fall all the time, while others can remain mildly affected and only show limited signs of incoordination. Some dogs plateau and their clinical signs can remain static for long periods of time, while others can slowly progress over months to years.

CA is a constant condition. Affected dogs always have the disability, though it may not be evident with all motion. Clinical signs of CA are most evident when observing complex movements, such as running and stairwalking. Such complex maneuvers are more than most CA affected dogs can deal with through their ability to concentrate.

Some Old English Sheepdogs affected with CA can compensate for the lack of proprioceptive control by watching where they place their feet, and consciously “learning” everyday movements that would be automatic for any other dog. Some dogs that have a specific set of stairs that they use every day, can learn to place one foot at a time, and get up and down cleanly. For these dogs, their clinical signs become more evident when they are tired or excited (and can’t concentrate as well). For this reason the classical signs of CA may be most evident when running and chasing a ball, or doing a “new” set of stairs that the dog may not be used to.

Because of the ability for some CA affected dogs to compensate, their clinical signs of incoordination may appear episodic, rather than constant. If an owner only sees the signs when the dog is running, they may think that the running causes the onset of signs.

Together with Dr. Natasha Olby (North Carolina State Univ.) and Dr. Alexander de Lahunta (retired, Cornell Univ.), we have been studying cerebellar abiotrophy in several animal species and several breeds of dogs. Each breed with CA has the same pathological cause; that being the degeneration of the Purkinje cells of the cerebellum. The dog breeds with the most similar CA presentations as the Old English Sheepdog include the Gordon Setter, Scottish Terrier, American Staffordshire Terrier, and Spinone Italiano. All of these breeds show a later onset, slowly progressive form of CA.

Each breed has its own specific characteristics of the disorder. In the Gordon Setter, the onset of CA is 4 to 12 months of age, with most owners recognizing the incoordination by 1 to 3 years of age. The American Staffordshire Terrier has a much later age of onset – usually recognized between 3 to 5 years of age. There are Scottish Terriers with CA whose owners believe that they first recognized clinical signs at 5 to 10 weeks of age, and some with very mildly affected dogs that did not recognize the clinical signs until 3-5 years of age. In the Old English Sheepdog, the clinical signs can be mild, and are usually recognized between 1-5 year of age.

The most definitive diagnosis of CA is through a pathological examination of the brain and cerebellum after death. The degeneration of the Purkinje cells (with the secondary changes that occur due to this degeneration) confirms the pathological diagnosis. Because of the size of the Purkinje cells, their cellular processes (axons and dendrites), and the stimulation of the cells that they connect to, there is a gross reduction in size and weight of the cerebellum compared to the rest of the brain in CA affected dogs.

The reduction in size of the cerebellum can be measured by magnetic resonance imaging (MRI) in a live dog, and has been used as another diagnostic parameter in CA affected dogs. This was documented in South African CA affected Scottish Terriers in a veterinary journal article. However, at this time, the extent of degeneration that is necessary to cause a measurable gross reduction in the size of the cerebellum has not been established. Because of this, an MRI may not be able to diagnose CA in dogs who are young, whose disease process is not longstanding, or whose clinical signs (and therefore the amount of Purkinje cell degeneration) are mild. The criteria for MRI diagnosis in CA affected dogs with different degrees of severity are one aspect of the ongoing CA research.

As most Old English Sheepdogs with CA are expected to live a normal lifespan, the majority of CA affected Old English Sheepdogs will receive a clinical diagnosis of the disorder. It would be unfair and wrong to euthanize these special dogs simply to establish a pathological diagnosis. A clinical diagnosis of CA requires documentation of the specific clinical history, progression, and neurological signs that are consistent with the condition, and that rule out other causes. This can be a confusing process to an owner that does not understand the differences in movement between a dog affected with CA, and other dogs whose movement disorders can be due to other causes.

Other disorders that can cause clinical signs of an abnormal gait include brain infections (encephalitis), toxins, injury, spinal cord disorders, luxating patellas, and other musculoskeletal abnormalities. CA affects all four limbs. The signs are always symmetrical between the left and right sides of the body, although either the forelimbs or the hindlimbs may be more severely affected in each dog. This differentiation eliminates most musculoskeletal abnormalities. Spinal cord abnormalities (including “Wobblers” and intervertebral disc disease) cause pain and weakness, as well as either a sinking or stilted gait (depending on the location of the lesion in the spinal cord).

Encephalitis and toxins will cause more injury in the brain than just the Purkinje cells, and this will be evident in the clinical examination. There are no toxins found to selectively affect just the cerebellar Purkinje cells. Infections and toxins will also present with an acute onset, and more rapid progression than seen with CA. These same differences will be evident with a brain injury. The cerebellum is in a protected area of the skull. If this area of the brain were injured, the clinical signs would be representative of more than a pure Purkinje cell degeneration. In addition, all of these conditions are likely to present with asymmetrical clinical signs.

A clinical diagnosis of cerebellar abiotrophy is best obtained through a neurological examination by an ACVIM board-certified neurologist, in consultation with Dr. Olby. I also offer a videotape review of dogs suspected of being affected with CA with Dr. de Lahunta. In order to make a clinical diagnosis based on videotape, the classical movements that would separate CA from other disorders during a neurological examination need to be present. The clinical history and progression of the clinical signs must also be compatible with CA.

The specific neurological movements of CA that must be present on a videotape for a clinical diagnosis are best shown when stairwalking, and running or chasing a toy off lead. There are several owners who have submitted videotapes of their Old English Sheepdogs that probably have CA. However, a clinical diagnosis has not been offered in these dogs, because the confirming and ruling out movements are not present in the video. In these cases, we recommend that the dog be examined by a neurologist.

CA is not the most prevalent or most important hereditary condition affecting Old English Sheepdogs. However, it is a condition that is being diagnosed worldwide in the Old English Sheepdog, has a simple autosomal recessive mode of inheritance, and has a wide pedigree base that does not preclude any Old English Sheepdog from being affected. With the cooperative efforts of the breeders, owners, and researchers, we should be able to deal with CA, and thus improve this particular health aspect for the Old English Sheepdog breed.

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For permission to reprint this article, please contact Dr. Jerold S. Bell: jerold.bell@tufts.edu

THE OLD ENGLISH SHEEPDOG

The Drover's Best Friend

To describe the characteristics, temperament and capacity for training of the Old English Sheepdog, one must first understand the trade of droving which dates back to ancient times in Britain. A drover was described as a licensed individual of outstanding character, responsible for taking vast herds of animals numbering from in the hundreds to the thousands—cattle, sheep, pigs, turkeys and geese—to market, and collecting money for the owners of the animals. The drover's route took days, as some roads were over a hundred miles long. A hard-working, intelligent herding dog was essential, but not one that would overwork the herds and the flocks, as the animals had to arrive safely and in good weight to receive the best market value.

The drover's dog had to adapt to constant shifts in environment—moving from the farm to the travel route to the marketplace—as well as to changing weather. Life on the road was harsh, so the dog had to have a weatherproof coat. This special dog needed to be a steady and enthusiastic worker, tireless, loyal and watchful. He had to protect his flocks from predators, yet control the herds without viciousness, and have an innate ability to sense his master's wishes.

A collection of historical stories compiled by Ray Owen in The Very Old English Sheepdog (2000), includes many remarkable accounts of drovers and their dogs. When the drovers were finished the trek to market, they would often send their sheepdogs home, while the drovers remained at market. These highly intelligent Bobtails would make the return trip by themselves, stopping at taverns where they would be fed and watered on the drover's account. On the next trip, the drover would settle his sheepdogs' "tab." Some dogs were even entrusted to take the purse of money home to the owner of the herd. Many a drover would advertise his route, picking up new stock along the way, adding to the workload and responsibilities of the dog.

The breed was first shown at a conformation dog show in England in 1865, and by 1873, the OES was given a separate breed classification with the Kennel Club, and three OES competitors exhibited at the Curzon Hall Show in Birmingham, England.

The first registrations were recorded in 1877. In 1888, there was an entry of 20 and by 1899, 50 OES were entered at a Kennel Club show. The Old English Sheepdog Club (of England) was founded in 1888 and the breed was officially recognized by AKC in the same year.

Square, Strong and Healthy

The breed standard drawn up in late 19th-century England (1885) outlined the desirable conformation and temperament traits. This standard was adopted in Canada when OES were first imported to this country and has changed somewhat over the years. Historical records list two OES among CKC registrations for 1902-03.

Today, the OES retains the qualities valued by both the first exhibitors-breeders and drovers. The physical attributes remain the same and the herding instinct is intact. This squarely built dog has a thickset, muscular body that provides both strength and agility. One distinguishing breed characteristic is an unusual topline, which slopes from loin to withers, as well as the long, harsh, shaggy coat which comes in shades of grey, grizzle, blue or blue merle, with or without white markings. The dog is generally white on the head and shoulders with patches of grey, and grey from the shoulder back with occasional white splashes. Any shade of brown or fawn is unacceptable. His unique double coat consists of a soft undercoat and a harsh water- and dirt-repellent outer coat made up of "guard hairs." The coat is woolly, and when wet, smells a bit like a damp wool sweater.

Most popular breeds have an oily hair coat and hair that is shed sticks to clothes and furniture. Much to the surprise of prospective pet owners, the OES does not shed, and elicits far fewer allergic reactions than most breeds. If kept long, the double coat requires regular line brushing to keep it healthy and free of matting. Regular trips to the groomer can ensure the coat is kept short and easy to care for, or pet owners can easily learn to groom with the guidance of a breeder or professional groomer. Most dogs enjoy being groomed and look forward to their turn on the table.

Popular mythology claims that if you cut the "shaggy bangs" exposing his eyes, the Old English will go blind. Rubbish! An innately watchful creature, this dog likes to see what is going on just as much as we do. For that reason, you will often see them with hair pulled back and fastened with an elastic or barrette.

According to the breed standard, the size is 22 inches and upwards for dogs, slightly less for bitches. However, today's dogs are generally larger. The head should be square with plenty of room for brain power and well-covered with shaggy hair. Eyes may be dark brown, or any shade of blue. Occasionally, a dog will have one eye of each colour; this is also acceptable. The nose should be large and black. Puppies are frequently born with pink noses which gradually turn black. Teeth are strong, large and level in opposition.

The CKC standard describes the OES as a strong and compact specimen "of great symmetry, practically the same measurement from shoulder to stern as in height, absolutely free of legginess, very elastic in his gallop, but in walking or trotting he has a characteristic ambling movement ...." His neck should be fairly long and arched gracefully, with shoulders well laid-back for reaching, and quick turning capacity. The hind should be round and muscular and the hocks should be well let-down and perpendicular to the ground.

Their lifespan averages between 10 and 12 years, and certainly many have lived longer. They remain fun-loving puppies in attitude throughout their lives. There are no aliments which are unique to them; rather they face the  same health concerns which afflict all large breeds. Hip dysplasia, thyroid disease and eye problems are the primary health concerns. Occurring far less frequently are cerebella ataxia, gastric torsion and deafness. Reputable breeders will have health tests done on hips, eyes and hearing.

Living with "The Shaggy Dog"

The breed is blessed with a cornucopia of wonderful traits: amiable, gentle, jolly, even-tempered, adaptable, friendly, faithful, protective, alert and intelligent. While originally bred to be a hardy working dog capable of independent actions, often without supervision for extended periods, OES are in every respect a superb companion dog and are wonderful with children, although perhaps a bit rambunctious during puppyhood for very young children. The modern Old English Sheepdog never strays far from his owner or home. He always watches and makes every effort to anticipate his master's next move. Many who have owned the breed say they exhibit a sense of humour and are widely claimed as the clowns of the dog world. Both males and females are equally affectionate.

Easily motivated by praise, their behaviour can be reinforced with interesting challenges. OES love agility, scent hurdles, herding trials, and obedience's open and utility exercises (although they quickly become bored with the precision work of heeling). They are enthusiastic to learn new activities, and enjoy nothing better than spending time outdoors with their owners. Once taught their place in the family structure and given adequate guidance, the Old English is a valued, affectionate and self-regulating family member, with a predictable and reliable temperament.

Judging the OES: Look Beyond the Coat

by Terry Carter

There are few breeds whose conformation, good or bad, is as well-hidden as that of the OES. First, the heavy, thick coat obscures the dog underneath; secondly, "artistic" grooming can enhance a less-than-ideal feature, or less skillful grooming can make good qualities very hard to find. Because of this, it is essential that judges of our breed learn to properly use their hands for assessing the dog.

In general appearance, the OES should look strong, compact and square, as called for in the CKC standard. The AKC standard also emphasizes a square dog: "Length, measured from the point of shoulder to point of ischium (tuberosity), practically the same as height." His length of leg should be equal to his depth of body. Be aware that excessive trimming over the hind quarters can make a longish dog look shorter than he is, and a heavy coat in front of the forechest and behind the rear can make a dog that is in fact square look long. You must put your hands into the coat to find out the true structure of the dog.

The head is definitely one area where you will not truly know what it is like until you go over it with your hands. The stop should be well-defined (please note this is missing in the Canadian standard). Put your thumb at the bottom of the stop and spread your hand over the backskull. Your hand should barely extend to the occiput in an average size male and the width should be approximately the same. The muzzle should be about two-thirds the length of the backskull. The British changed their standard to equal length nearly a decade ago and in the opinion of many, truncation (bluntly squared off) of the muzzle is lost.

Eyes can be dark brown or blue and a split eye (blue-and-brown in the same eye) is sometimes seen. Our standard does not call for pigmentation of the eye rims and although it is more attractive, this should not enter your decision-making.

The neck is "fairly long, arched gracefully" and blends smoothly into nice, clean, sloping shoulders. Again, you must run your hand down the neck and over the shoulder as the neck of a heavily coated dog will not be easily seen and the neck of one that is quite stripped will appear longer than it is.

Your hand should run along the topline, discovering a gentle rise to the loin which should be short, thick, and muscular. The rear is muscular and well-rounded. The ribs are well-sprung but not barrel-chested, which usually leads to coarse shoulders.

The forelegs are dead straight and well-boned with a round tight foot. The OES is not a wide-chested breed and he should be wider in the rear. His hocks should be "well-let-down" with no cow hocks or barrel hocks. Again, you must run your hands down the legs.

Puppies are born black and gradually change to a harsh grey coat as adults. An adult coat should feel hard and have a break to it. There is a dense, soft undercoat. Show dogs are washed very frequently which tends to soften the coat, so feel for texture in the grey hair. The hams are a good place to check coat texture. Do not expect a harsh coat in a puppy but in older puppies or adolescents, separate the coat and you should see the beginnings of guard hair coming in. You can also do this if you are querying whether the dog presented to you has the coat he was born with or heavily enhanced.

In some cases, OES grooming has become very extreme and looks cartoonish. I do not feel OES need to have their coat backcombed. A good coat will be thick enough to stand out from the body and some judges will ask for backcombing to be removed before judging. The coat on the head may need backcombing so that the dog can see properly, as we have bred more coat in than they need. Also the head coat is washed so often that it will probably lay flat if not helped.

Markings should not influence your decision and white splashes in the body or dark markings on the head or in the white are of no consequence. Adolescent dogs often go through very washed-out coat stages or sometimes turn brownish as the puppy coat dies. Please check the roots to see what the colour is before penalizing for a brown coat. An adult should definitely have a grey coat.

"Soundness should be considered of greatest importance," says our standard. However, I think exhibitors sometimes interpret this to mean the fastest is the best. The Old English should have a nice, easy, ground-covering gait when moved at a trot. Legs flailing in all directions are not correct. When moved at slower speeds, they will naturally amble or pace. This is correct and it is the gait used when they move stock; they can go for miles at this speed and when used as drovers' dogs, they did. The OES roll is more easily seen at a slower speed. This roll is in the rear not the front. Movement in the show ring is universally judged at a trot but keep in mind that these other movements are typical of our breed and some judges will move them at two speeds. When moving OES away from you, watch their feet as it is easy to be deceived by hair. It takes a while to learn to judge movement in coated dogs and any time spent learning ringside is worthwhile.

I would hope that judges will enjoy judging our breed and not view it as a large puffball but as a credible member of the herding group.

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Reprinted with permission - Canine Review - August 2012 issue

DIETA BARF - HUESOS RECREATIVOS

Los huesos recreativos son aquellos huesos que por su naturaleza son grandes y duros. Estos huesos no forman parte directamente en su dieta (aunque si indirectamente) ya que se usan principalmente para entretener a nuestros perros.

¿Que tipos de huesos recreativos existen?

Aunque se puede usar muchos tipos de huesos recreativos, mayoritariamente se clasifican en dos tipos:

• Hueso esponjoso: Son huesos más suaves, normalmente se encuentran en los extremos. Un ejemplo claro de hueso esponjoso podría ser el lateral de un fémur (rodilla).
• Hueso compacto: Son huesos sólidos, normalmente se encuentran en la parte larga central. En el caso de fémur suele venir acompañada de médula. 

Recordar que aunque sean huesos grandes y duros nunca deben darse cocidos ya que aumenta el peligro de que se astillen.

¿Cada cuanto hay que ofrecerle huesos recreativos?

La respuesta es "depende", ya que cada perro es un mundo. Habrán perros que el hueso no le dure ni una hora y a otros que les duren días. También comentar que por higiene no le daría el mismo hueso más de dos días seguidos.

En cuento a la frecuencia le sería de 1 a 2 a la semana.

¿Que beneficios aportan los huesos recreativos?

Estos huesos son usados mayoritariamente para la limpieza de los dientes. A diferencia de los típicos Dentastix, que únicamente reducen la acumulación de nuevo sarro, los huesos recreativos disminuyen notablemente el sarro de los dientes. Se debe tener en cuenta que con la disminución del sarro en los diente el aliento de nuestros perros mejorará,

Como bien hemos comentado antes, estos huesos se usan para entretener a nuestro perro. Al masticar, el perro reduce el estrés acumulado, siendo un gran aliado para que el perro pueda permanecer tranquilo.

Al rozar el huesos con los dientes, este se lleva diminutos trozos del huesos, siendo un aliado eficaz para aumentar el calcio que debe ingerir los perros. Además según el tipo de hueso que elijamos tendrá los siguientes beneficios:

• Huesos esponjoso: Suelen estar recubiertos de más carne y cartígalo. Además son mas fácil de roer, por lo que la absorción de calcio será mayor.

• Huesos compacto: El interior de estos huesos este recubierta de médula (hablaremos más adelante de ella) que les encanta a los perros. Son muy extremadamente duros, por lo que da la "garantía" que el perro no los romperá.

¿Qué es la médula?

La médula, también llamado tuétano, es la sustancia grasa de color blanca que se encuentra en el interior de los huesos como el fémur. Esta sustancia es altamente grasas (al rededor del 90%) y rica en hierro, por lo que es un alimento que se recomienda a perros que llevan un actividad diaria muy alta. Además tiene pequeñas porciones de tiamina, niacina, vitaminas A, E, D y K, magnesio, calcio y zinc.

¿Qué desventajas aportan los huesos recreativos?

Las desventajas son pocas. La más notable es que estos huesos deben ser recreativos y no deben ser ingeridos en su totalidad, por lo que deberemos estar atentos cuando estén con ellos y desecharlo o guardarlo en la nevera cuando no podamos estar pendientes. 

Aunque no es el objetivo, no debemos alarmarnos en el caso de que ingiera el hueso recreativo en su totalidad. Si bien es cierto existe la posibilidad de sufrir los siguiente síntomas:

• Estreñimiento: Un consumo muy elevada de huesos en poco tiempo causa este problema. Para apaciguarlo se puede incorporar más vegetales a la dieta que aporten fibra.
• Exceso de calcio: Si además de su dieta, se le da muchos huesos recreativos y encima son ingeridos.
• Que se astillen o se atoren: Aunque el porcentaje es bajo, existe la posibilidad y es mayor que la de los huesos carnosos.

Experiencia personal-  Los huesos son una excelente manera de mantener la salud bucal de nuestros OES.  Si bien hay mucha controversia sobre ellos en la alimentación canina, son los mejores destresantes que hay.  Recomiendo los huesos de rodilla que son grandes y pueden durarles hasta varios días. Descartar huesos de asado, y pollo, y nada de huesos cocidos porque pueden astillarse fácilmente.