Streptococcus uberis: A Permanent Barrier to the Control of Bovine Mastitis?

The prevalence of bovine mastitis has been reduced over the past 25 years due to the implementation of a five-point control plan aimed at reducing exposure, duration and transmission of intramammary infections by bacteria. This has markedly reduced the incidence of bovine mastitis caused by bacteria which show a contagious route of transmission, but has had little effect on the incidence of mastitis due to bacteria which infect the gland from an environmental reservoir. Streptococcus uberis is one such bacterium which is responsible for a significant proportion of clinical mastitis worldwide.The inadequacies of the current methods of mastitis control have led to the search for additional measures, particularly vaccines to prevent intramammary infection by this bacterium. Such an approach requires detailed knowledge of the pathogenesis of intramammary infection. Our understanding of this area has grown in recent years but a lack of information still hampers disease control. Both live vaccines and, recently, crude sub-unit vaccines have shown promise against bovine mastitis due to S. uberis. Vaccines against mastitis must, however, be able to control infection without the participation of a marked inflammatory response. This review provides an overview of the recent advances which have been made in our understanding of host-pathogen interactions which promote infection and disease and highlights areas for strategic research aimed at controlling this bacterial infection.     

Is the Male Dog Comparable to Human? A Histological Study of the Muscle Systems of the Lower Urinary Tract

Because of their superficial anatomical resemblance, the male dog seems to be suitable for studying the physiologic and pathological alterations of the bladder neck of human males. The present study was carried out to compare and contrast the muscular anatomy of the male dog lower urinary tract with that of humans. The complete lower urinary tract, including the surrounding organs (bulb of penis, prostate, rectum and musculature of the pelvic floor) were removed from adult and newborn male dogs and histologically processed using serial section technique. Based on our own histological investigations, three-dimensional (3D)-models of the anatomy of the lower urinary tract were constructed to depict the corresponding structures and the differences between the species. The results of this study confirm that the lower urinary tract of the male dog bears some anatomical resemblance (musculus detrusor vesicae, prostate, prostatic and membranous urethra) to man. As with human males, the two parts of the musculus sphincter urethrae (glaber and transversostriatus) are evident in the canine bladder neck. Nevertheless, considerable differences in formation of individual muscles should be noted. In male dogs, no separate anatomic entity can be identified as vesical or internal sphincter. The individual course of the ventral and lateral longitudinal musculature and of the circularly arranged smooth musculature of the urethra is different to that of humans. Differences in the anatomy of individual muscles of the bladder neck in the male dog and man suggest that physiological interpretations of urethral functions obtained in one species cannot be attributed without qualification to the other.     

The Friesian horse breed: A clinical challenge to the equine veterinarian?

The Friesian horse breed is a beautiful breed for showing, riding and driving. However, some clinical problems seem to have a higher incidence in the Friesian breed compared to other breeds and this raises suspicions that these clinical entities may have a genetic basis.     

Nutritional requirements of meat-type and egg-type ducks: what do we know?

The demand for duck meat, duck eggs, and associated products is increasing each year. Classic and modern selection programs have been applied to enhance the economic traits of ducks to satisfy the requirements of consumers and enhance the incomes of producers. The nutritional requirements of unselected ducks may not be adequate, however, to fulfill the potential productivity performance of modern birds, including both meat-type and egg-type ducks. In particular, an imbalanced diet is associated with low productive performance and signs of nutritional deficiency(if insufficient nutrients are supplied), as well as with high feed costs and manure problems that reflect flock health and welfare(if excessive nutrients are supplied). Thus, the main aim of this review is to summarize the results of previous studies that estimated the nutrient requirements of meat-type and egg-type ducks in order to evaluate current knowledge and to identify further issues that need to be addressed. In addition,the results obtained in previous studies are compared in order to understand how to lower commercial feed costs,fulfill the genetic potential of selected ducks, protect the environment from pollution, and satisfy the welfare and health needs of ducks.     

Rotavirus gastroenteritis: why to back up the development of new vaccines?

Rotaviruses (RVs) are the main aetiologic agent of severe acute diarrhoea in children under the age of 5, worldwide. Given that the currently available preventive measures to fight against the transmission of RV disease are not sufficiently effective, vaccination likely represents the only efficacious adapted response to the massive impact of this infection. Although the two current RV vaccines have shown good tolerance and significant efficacy to protect infant against severe RV disease, their development have raised key questions that are still unanswered regarding their cost, efficacy and safety. These two vaccines have in common the disadvantages related to the use of oral attenuated live viruses which limit their implementation in both developed and developing countries. In order to overcome these hurdles, it is important to support the development of new, non-replicating vaccines which will not suffer the potential disadvantages of the present vaccines. New approaches and other routes of administration are being tested in animal models and soon will be evaluated in humans. Among those are viral-like particle-based vaccines which have provided the most promising results. Finally, the epidemiology of the disease which differs in developed and developing countries can affect decisions about vaccine composition and delivery. The answer brought by the development of new RV vaccines could reside in developing several types of RV vaccines specifically designed to be used in different settings.     

Changes in Equine Reproduction: Have They Been Good or Bad for the Horse Industry?

In the past four decades there have been tremendous changes in equine reproduction. Most breeds now allow the use of artificial insemination with fresh, cooled and frozen semen. Artificial insemination has many advantages for the breeder, in particular the control of bacteria through the use of semen extenders containing antibiotics. Deposition of sperm in small volumes onto the uterotubal junction has allowed the use of relatively low numbers of sperm. Intracytoplasmic injection of sperm into oocytes allows older, subfertile stallions to be used as breeding stallions. Advances in mare reproduction have included developing tools for hastening the onset of the breeding season. Other advances include embryo transfer, oocyte collection and transfer, and cloning. The acceptance of reproductive technology depends on the success of the technology, the attitude of the breeders/veterinarians, and the cost/benefit ratio to the industry and breed registry.     

Pathogenesis of osteochondrosis dissecans: How does this translate to management of the clinical case?

Osteochondrosis (OC) is the most prevalent developmental orthopaedic disease in the horse. It is a complex disorder because of the interplay of factors that influence the formation of lesions and the ensuing natural healing process, the end result of which determines clinical outcome. The early pathogenetic mechanism of OC has long remained elusive, but recent research has provided compelling evidence for vascular disturbances leading to areas of ischaemic necrosis in the subarticular growth cartilage as the primary event. The aetiological factors that influence the process of the development of lesions are many and comprise both genetic and environmental factors. The genetic background of OC (dissecans) is highly complex with quantitative trait loci associated with some form of OC found on not fewer than 22 of the 33 chromosomes of the horse, and different manifestations and locations of OC having probably different genetic backgrounds. The environmental factors can be divided into nutritional factors and factors influencing the biomechanical loading of joints. Feeding large quantities of easily digestible carbohydrates is a clear risk factor and also the availability of sufficient copper for mares in the last part of pregnancy is important. Factors influencing the biomechanical loading of joints include the exercise regimen of foals, paddock size and roughness of terrain, and conformation. Equine OC is rarely a life‐threatening disease and the prognosis of (surgical) treatment is good to very good. However, the impact on economics of the equine industry and on horse welfare is large. This impact can only be lessened by the judicious management of both horse breeding and horse husbandry. Some of the measures that would alleviate the burden of OC conflict with (commercial) pressures from the industry and a balance between human‐imposed breeding and performance goals and the interest of the animal itself should be sought.