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Neosporosis is an infectious disease of cattle and other species with a worldwide distribution. In Poland, the seropositivity rate for N. caninum among dairy cattle varies between 6% and 80%, with the highest number of seropositive cows in central and north-eastern voivodeships. In the United States, in 2003 the total annual cost of N. caninum infections was 657 million dollars, and in Great Britain in 2014 it was nearly 14 million pounds. N. caninum results in severe economic losses caused by a decreased milk yield, an increased number of culled cows, a higher newborn calf mortality rate and occasional birth defects. However, the most common result of this disease is abortion, which usually occurs between the 5th and 7th month of gestation. The risk of aborting is 3 times as high for seropositive cows as it is for seronegative cows; up to 21.6% vs. 7.3%, respectively. Cattle can become infected by consuming food and water contaminated with N. caninum oocysts, but the principal route is transplacental transmission usually between the 70th and 210th day of gestation. The ELISA test is most often used to detect the presence of specific antibodies in blood serum. PAG-2 level in the bloodstream can be a good marker for predicting Neospora-induced abortions – in seropositive cows, a level of more than 4.5 ng/ml on the 120th day of gestation means a 7-fold higher risk of pregnancy loss. According to research, live attenuated vaccines are highly efficacious in preventing neosporosis. Unfortunately, the currently available methods of prevention are based on the elimination of seropositive cows from the herd and the limitation of contact with the final hosts of N. caninum.
The aim of this article is to set out certain possibilities related to the simplification of the superovulation protocols (SOV) in cattle. The traditional protocols, which have been in use for decades, include as standard several injections of FSH preparations. Due to the widespread increase in the importance of the animals’ welfare, alternative options for its administration are now being sought. Appropriate selection of gonadotropin as well as the dose and ratio of hormones makes it possible to limit undesirable effects such as prolonged ovarian stimulation. Adjuvants such as polyvinylpyrrolidone, polyethylene glycol, hyaluronic acid or aluminium hydroxide enable the extension of the absorption time of FSH preparations, thus reducing the amount of FSH injections. A single deposition of hormones dissolved in aqueous solutions is possible when it is administered via alternative routes, such as subcutaneous or epidural. Reduction of the amount of FSH injections may directly translate into a decrease of the stress level in animals treated by the SOV protocols and also to the improvement of the efficiency of embryo production. A significant risk factor remains the high variability of superovulation. Its effectiveness depends on a number of generally well known individual and environmental factors that should also be considered when joining SOV.
Rectal palpation has been an integral part of a clinical examination of large animals. This seemingly easy technique can pose certain difficulties for veterinarians and therefore requires considerable training. The rectal examination course included in the traditional program of veterinary studies is mainly based on practical classes with live animals. However, there is a common belief that the use of live patients is burdened with certain disadvantages in the form of a lack of control over the student’s actions. What is more, a rectal palpation can have a negative effect on the animal organism. Following the increased focus on animal welfare in society and taking into account both ethical and medical concerns, a number of alternative teaching devices have appeared on the market in order to replace or significantly reduce the participation of live animals in the didactic process. Breed’n Betsy – one of the first simulators – is used to teach the diagnosis of the oestrus cycle and pregnancy phase as well as the artificial insemination or the embryo transfer. The appliance was soon followed by more technically advanced didactic equipment. Simulators, such as Haptic Cow, use virtual reality and haptic technology. The computer-generated, virtual objects representing the cow’s anatomical structure are displayed on the screen. This technique enables the tutor to follow student’s movements “inside the cow” and provide them with immediate instructions. Numerous studies indicate that the use of simulators, integrated with the traditional teaching techniques, brings highly satisfactory results.
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