Clinical, haematological and biochemical findings in foals with neonatal Equine herpesvirus-1 infection compared with septic and premature foals

NOVEL SIMPLEXVIRUS (SIMPLEXVIRUS DOLICHOTINEALPHA1) ASSOCIATED WITH FATALITY IN FOUR PATAGONIAN MARA (DOLICHOTIS PATAGONUM)

Four of seven Patagonian maras (Dolichotis patagonum) at a zoological institution developed acute neurologic signs that progressed to tetraparesis and death. All affected were young adult females (10 mon-5 yr old) that presented over 11 d. Clinical signs were rapidly progressive and unresponsive to supportive therapies. Two of the four individuals were found deceased 4 d after hospitalization. Two individuals were euthanized due to poor prognosis and decline after 6 and 8 d, respectively. Simultaneously, an additional mara developed mild and self-resolving clinical signs, including a kyphotic gait and paraparesis. On gross examination, there were widespread petechiae and ecchymoses of the skeletal muscle, myocardium, skin, pericardium, urinary bladder mucosa, and spinal cord. On histopathology, all animals had necrotizing myelitis and rhombencephalitis, with intranuclear viral inclusions in three individuals. Electron microscopy confirmed herpesviral replication and assembly complexes in neurons and oligodendrocytes. Consensus PCR performed on spinal cord, brainstem, or cerebellum revealed a novel Simplexvirus most closely related to Simplexvirus leporidalpha 4. The virus was amplified and sequenced and is referred to as Simplexvirus dolichotinealpha1. It is unknown whether this virus is endemic in Patagonian mara or whether it represents an aberrant host species. Clinicians should be aware of this virus and its potential to cause severe, rapidly progressive, life-threatening disease in this species.

Equine Herpesvirus-I Infection in Horses: Recent Updates on its Pathogenicity, Vaccination, and Preventive Management Strategies

Equine herpesvirus-1 (EHV-1) is one of the most common and ubiquitous viral pathogens infecting equines, particularly horses worldwide. The EHV-1 is known to induce not only humoral but also cellular immune responses in horses. Respiratory distress, abortion in pregnant mares, neurological disorders, and neonatal foal deaths represent EHV-1 infection. Despite the limited success of inactivated, subunit, live, and DNA vaccines, over the past few decades, vaccination remains the prime preventive option to combat EHV-1 infection in horses. However, current vaccines lack the potentiality to protect the neurological form of infections in horses. There is desperate necessity to search effectual EHV-1 vaccines that may stimulate not only mucosal and systemic cellular immunity but also humoral immunity in the horses. This review highlights the state of knowledge regarding EHV-1 biology, EHV-1 pathogenesis, and disparate vaccines studied in the past to prevent EHV-1 infection. The review also underlines the best management strategies which certainly need to be adopted by veterinarians in order to avoid and prevent EHV-1 infection and outbreak in horses in the future.

Update on interstitial pneumonia

Interstitial pneumonias encompass a wide variety of acute and chronic respiratory diseases and include the specific diseases equine multinodular pulmonary fibrosis and acute lung injury and acute respiratory distress. These diseases have been diagnosed in all age groups of horses, and numerous agents have been identified as potential causes of interstitial pneumonia. Despite the varied causes, interstitial pneumonia is uniformly recognized by the severity of respiratory disease and often poor clinical outcome. This article reviews the causal agents that have been associated with the development of interstitial pneumonia in horses. Pathophysiology, clinical diagnosis, and treatment options are discussed.

Lower respiratory problems of the neonate

The newborn foal can experience problems of the lower respiratory tract that are unique to the neonate. The transition to extrauterine life usually occurs rapidly and in a coordinated manner, but problems associated with the peripartum period, including placentitis, dystocia, infection, and trauma, can result in conditions that compromise gas exchange in the newborn foal. This article reviews the normal transition and presents some of the problems seen in these small patients.