Dural and deep cervical musculature anesthetic blockade for atlantoaxial collection of cerebrospinal fluid in horses.

The analysis of cerebrospinal fluid has diagnostic, prognostic, and therapeutic value in neurological illnesses in horses. There are different methods for obtaining cerebrospinal fluid, with the collection between the C1 and C2 vertebrae being a more recent methodology, which allows the procedure to be performed in standing patients, without the limitations of general anesthesia and with a low contamination of the sample with blood, presenting itself as a practical alternative. This study evaluated the efficacy and safety of a local dural blockade in healthy horses submitted to cerebrospinal fluid collection by atlantoaxial puncture and the quality of the samples obtained by this procedure, which were submitted to physical, chemical, and cytological analyses. The animals were evaluated considering aspects such as pain, sensitivity, the presence of edema, temperature variations, and ultrasonographic alterations post-collection. Discrete local changes were observed after the puncture, and the procedure was considered safe and simple to perform. Lidocaine blockade could reduce the reaction elicited by the needle passing through the dura mater, and the samples obtained showed satisfactory quality and laboratory results consistent with the values compiled in the literature. Transient hyperthermia was observed in 70% (7/10) of the animals in the dural blockade group, and 80%(8/10) of the patients from the control group, totalizing 75% of all individuals evaluated. The rectal temperature alteration was observed 4 to 12 hours after the procedure and was entirely resolved without intervention by the 24-hour evaluation.

Hereditary myotonia in American Bulldog associated with a novel frameshift mutation in the CLCN1 gene.

Hereditary myotonia (HM) is a genetic disorder that occurs due to mutations in the chloride channel and results in delayed relaxation of the skeletal muscles. HM has been described in 12 dog breeds, and in five of them, molecular studies of this disorder were performed and mutations in the CLCN1 gene were described. In this study, an affected American Bulldog with HM clinically characterized by muscle hypertrophy, myotonic discharges, and nondystrophic myotonia with a "warm-up" phenomenon was evaluated, and the candidate canine CLCN1 gene was sequenced. The molecular analysis revealed a frameshift mutation NM_001003124.2:c.436_437insCTCT that resulted in a frameshift and a premature stop codon NP_001003124.1:pTyr146SerfsTer49 . Two aberrant alternative CLCN1 transcripts were observed in an affected dog, the expected transcript with the 4 bp insertion, NM_001003124.2:r.436_437insctct, and an unexpected transcript containing parts of intron 6 in addition to the insertion in exon 4, NM_001003124.2:[r.436_437insctct;r.774_775ins79]. In conclusion, the frameshift mutation in the CLCN1 gene is associated with autosomal recessive HM in American Bulldog and this study constitutes the first description of the disease in this breed.

Validation of high-resolution melting analysis as a diagnostic tool for endothelin receptor B mutation in American Paint horses and allele frequency estimation.

Overo lethal white foal syndrome (OLWFS) is a genetic disorder caused by a dinucleotide mutation in the endothelin receptor type B (EDNRB) gene leading to the death of affected foals shortly after birth. The use of rapid and reliable genetic testing is imperative for the early diagnosis of the mutation avoiding, therefore, either additional suffering or the production of affected animals. In the present study, we developed and validated a high-resolution melting (HRM) genotyping assay to detect the OLWFS causative mutation, and we also determined the frequency of heterozygotes among American Paint horses in Brazil. The HRM genotyping assay resulted in a high sensitivity, specificity, and positive and negative predictive values. The overall estimated frequency of heterozygotes was 21.6%; however, this frequency increased to 89.5% when considering only overo horses. The HRM assay optimized here was a reliable and suitable method for the detection of the dinucleotide mutation observed in the EDNRB gene resulting in a fast, accurate, and precise diagnostic tool. The causative gene mutation of OLWFS is present in heterozygosity in the American Paint Horse population in Brazil and is highly frequent among overo horses.

Bartholin's gland adenoma in a Saanen goat / Adenoma de glândula de Bartholin em cabra da raça Saanen

ABSTRACT: Tumors affecting Bartholin's gland are considered rare in human medicine; there are few reports in the veterinary literature, with descriptions occurring only in cows. This article described the clinical and pathological findings associated with Bartholin's gland adenoma in a goat. Clinically, a 7-year-old pregnant Saanen goat presented bilateral enlargement of the vulva that did not regress spontaneously after parturition. Grossly, these vulvar masses were multilobulated, contained cystic areas from which oozed a whitish fluid. Histopathology revealed an adenoma characterized by the proliferation of irregularly shaped neoplastic epithelial cells that formed tubular to glandular-like structures. These neoplastic cells demonstrated moderate anisokaryosis and evident nucleoli. The intratumoral proliferation index (PI) was estimated by immunoreactivity with the protein ki-67. Further, the glandular-like structures produced a Periodic Acid-Schiff positive secretion. A diagnosis of Bartholin's gland adenoma was established due to the anatomic location of the neoplastic growths, the histopathological features, and the PI of the tumor.

RESUMO: Tumores que afetam a glândula de Bartholin são considerados raros em humanos e há poucos relatos na medicina veterinária, sendo descrito somente em vacas. Este artigo descreve os achados clínicos e patológicos associados ao adenoma na glândula de Bartholin em uma cabra. O animal da raça Saanen, com sete anos de idade e gestante apresentava aumento de volume bilateral na região da vulva, que não regrediu após o parto. Macroscopicamente, a massa era multilobulada, com presença de vários cistos preenchidos por uma secreção esbranquiçada. A histopatologia revelou um adenoma, caracterizado por proliferação de células epiteliais de formato irregular que formavam estruturas tubulares semelhantes à glândulas. Estas células neoplásicas apresentavam anisocariose moderada e nucléolos evidentes. O índice de proliferação celular intratumoral (PI) foi estimado por imunorreatividade à proteína ki-67. Além disso, a secreção produzida por essas estruturas do tipo glandular, foi positiva na coloração do Ácido Periódico-Schiff. O diagnóstico de adenoma da glândula de Bartholin foi estabelecido pela localização anatômica dos tumores neoplásicos, características histopatológicas e à PI do tumor.

Prevalência da mutação causadora da paralisia periódica hipercalêmica em equinos da raça Quarto de Milha no Brasil / Prevalence of the hypercalemic periodic paralysis mutation in Quarter Horses in Brazil

A paralisia periódica hipercalêmica (HYPP) é uma das principais enfermidades genéticas de caráter dominante que acometem cavalos da raça Quarto de milha (QM). A HYPP é causada por uma mutação pontual no gene SCN4A e, apesar de estar presente nos cavalos QM no Brasil, dados sobre a prevalência da HYPP são escassos. O objetivo deste trabalho foi verificar a prevalência da mutação responsável pela HYPP em cavalos QM, utilizados nas modalidades esportivas de rédeas (n=160), apartação (n=160), tambor e baliza (n=160), corrida (n=160) e conformação (n=101). Foram utilizados DNA sanguíneo dos 741 equinos; o teste genético para enfermidade foi padronizado e as amostras sequenciadas para identificação da mutação no gene alvo. A prevalência de HYPP na população amostrada foi de 4,2%, sendo que somente na linhagem de conformação foram identificados animais positivos (30,7%). Medidas de controle mais efetivas devem ser adotadas para diminuir a prevalência da HYPP.

Hyperkalemic Periodic Paralysis (HYPP) is one of the major dominant genetic diseases which affect Quarter horses (QH). The HYPP is caused by a point mutation in the SCN4A gene and despite the presence of HYPP in Brazilian QH, limited data on the disease prevalence are available. The aim of this study was to investigate the HYPP mutation in QH belonging to reining (n=160), cutting (n=160), barrel racing (n=160), racing (n=160) and halter (n=101) competitive disciplines. Blood DNA from 741 horses were used. Genetic tests were standardized and samples were sequenced to identify the mutation on the target gene. The prevalence of HYPP on the sampled population was 4.2% and the positive animals (30.7%) were only identified in the halter lineage. More effective actions on HYPP control should be done to reduce the disease prevalence. .