A lay summary

Recently published on the Veterinary Record Open was a study undertaken by Yoon-Hee Oh,Dong-Chan Moon, Young Ju Lee, Bang-Hun Hyun and Suk-Kyung Lim which evaluated the resistance of the P multocida bacterium against widely used antimicrobials to aid the most appropriate selection of drugs to use in affected animals. Resistance of bacteria is where therapeutic doses of antimicrobial medicine is administered, and bacteria continue to divide (APUA, 2014). There was an urgency to conduct this study due to the bacteria being one of the most significant causes of respiratory infection outbreaks in the Korean pig industry. Consequently, treatment failure due to resistant bacteria causes an increase in morbidity and mortality in pigs (Nedbalcová K. and Kučerová Z. 2013). Additionally, there is a concern of how the respiratory disease could pose a threat to the rest of the food chain.

In the present study, researchers used 454 isolates of the bacteria from all provinces in Korea over the period of 2010 to 2016 to evaluate the changes occurring in the resistance of P multocida to 18 antimicrobials used routinely to treat pigs. One of the reasons this study can be seen to be significant is the period of time that it took place over, along study over 6 years enables researchers to distinguish trends in the resistance and collate a large set of data that could aid other sectors such as veterinarians and surveillance stakeholders.

Strains of the P multocida were obtained from nasal swabs and lungs from diseased pigs from farms throughout Korea and used 5 isolates from each farm. These were then isolated on Columbia agar with 5% sheep blood. The researchers then tested the bacteria for the Minimum Inhibitory Concentration (MIC) by looking at their breakpoints, the concentration of the bacteria when it becomes susceptible to successful treatment (Mitka M, 2012). These were provided by the Clinical and Laboratory Standard Institute. The MIC90 refers to the MIC that inhibited 90 per cent of isolates.

When beginning to look the results of the research, it shows that P multocida isolates were defined to have multi-drug resistance (MDR) as they were found to be resistant to three or more different antimicrobials. From table 1, it can be seen that some isolates showed more resistance to some antimicrobials than others, with Sulphadimethoxine being the most frequently observed and Ceftiofur being the least. These figures are shown below:

Table 1 Resistance shown by the P multocida bacteria to different antimicrobials-§ indicates that a figure couldn’t be calculated because no Clinical and Laboratory Standards Institute interpretive criteria are available.

The second thing the results show in the report is that there was an increase in resistance to erolfloxacin over the period of the study increasing from 0 per cent of isolates in 2010-2011 to a resistance of 10.3 per cent in 2016. An explanation for this is suggested to be the increased usage of the antimicrobial over the past years, (AQPA, 2016). Although enrolfloxacin has been approved for the treatment of respiratory diseases in pigs, its cross-resistance with danofloxacin may have influenced the increasing MIC90 of danofloxacin as many isolates showed resistance to both antimicrobials.

An increase in the MIC90 values for neomycin, danofloxacin and penicillin 8 to 64 µg/ml, ≤0.125 – 2 µg/ml and, ≤0.125 to 0.25 µg/ml respectively was also observed which indicates that there is an increased amount of resistance to these.

Although there was no increase or decrease were observed for most antimicrobials, there was a frequent pattern for resistance seen from 50 percent of the isolates, with resistance shown with the following antimicrobials: sulphadimethoxine, chlortetracyline and oxytetracycline at 22.5 percent, sulphadimethoxine and oxytetracycline at 18.1 per cent and sulphadimethoxine on its own at 15.4 per cent. With this, MDR was found in 73 of the 453 isolates (16.1 per cent). It can also be seen that these figures were like those of other countries such as in Spain, where a study carried out by Lizaroano et al found 18.1 per cent of the isolates to have multi-drug resistance (Lizaroano et al, 2016).

With these results, it may then require a new antimicrobial to be looked at as therapeutic treatments to avoid promotion of multi-drug resistance increasing within the proportion of isolates. The study was the first of its kind on such a large scale, especially as clinical samples were collected from all nine provinces across Korea which allows for a more reliable and realistic study with results that can be used by the pig farmers and related professionals across Korea. It showed that the resistance rates in the present study for antimicrobials were higher than rates shown in previous studies in the EU (Garch El. et al, 2016) and North America (Sweeny MT et al, 2017).

The study concludes in highlighting the attention needed to the administration of antimicrobials in response the P multocida to prevent spreading of infection but also to prevent the increase of MDR and MIC. It may then lead to international collaborative studies which would help increase the knowledge on present resistance and formulate a better way of treating P multocida to reduce a future increase in resistance to antimicrobials. Further research, along with studies monitoring susceptibility of relevant pathogens would provide wider evidence and guidance when using antimicrobials to treat P multocida.

Reference list

APUA, http://emerald.tufts.edu/med/apua/about_issue/about_antibioticres.shtml

Animal and Plant Quarantine Agency (APQA). Antimicrobial use and antimicrobial resistance monitoring in animals and animal products. 2010. Gimcheon, South Korea, 2016.

El Garch F, de Jong A, Simjee S, et al. Monitoring of antimicrobial susceptibility of respiratory tract pathogens isolated from diseased cattle and pigs across Europe, 2009-2012: VetPath results. Vet Microbiol 2016; 194:11–22

Lizarazo YA, Ferri EF, de la Fuente AJ, et al. Evaluation of changes in antimicrobial susceptibility patterns of Pasteurella multocida subsp multocida isolates from pigs in Spain in 1987-1988 and 2003-2004. Am J Vet Res 2006; 67:663–8.

Nedbalcová K, Kučerová Z. Antimicrobial susceptibility of Pasteurella multocida and Haemophilus parasuis isolates associated with porcine pneumonia. Acta Veterinaria Brno 2013; 82:3–7.

Mitka M. Antibiotic Breakpoints. JAMA. 2012;307(10):1015. doi:10.1001/jama.2012.255

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Equine Euthanasia CPD

In a CPD course I completed through the Dechra Academy on 1st November 2018 I learnt about the goals of euthanasia in equines. The format of the course was an online interactive slide show split in to 4 sections, with questions within each section. The first topic covered was euthanasia consent and factors influencing a veterinarians choice to euthanise. Some of these factors include: location , the owner, the situation ( emergency or planned), disposal of the carcass and legalities.

In relation to location, the Welfare of Animals (Transport) Order 1997 states that “an unfit horse may be transported to the nearest place of slaughter providing the animal will not be subject to suffering by doing so and is under veterinary supervision”. The course informs that with this legislation in mind, vehicle access to remove the carcass must be available as well as something to cover the carcass while waiting for collection. When factoring the owner, euthanasia may be influenced by financial factors: lethal injections are more expensive than shooting the horse, for which the vet must hold a firearms licence. The owner also may not want to be present. Owners, if possible, should contact their insurance company before the euthanasia takes place as compensation may not be offered and the insurance company may want to view the carcass, which would affect carcass disposal.

In a planned euthanasia, an owner may have several reasons for taking this action. Some reasons may include: long term illness, the animal is no longer capable to do its job, behavioural issues that pose a threat to the horse and its environment, economic situation of the owner or the horses life is affected in one way or the other.

Emergency euthanasia is more complicated than a planned euthanising as the location may be compromising, safety of the surrounding people is highly important as the lethal injection is also a danger to humans. Disposal of the carcass in an emergency may be difficult to arrange in an emergency.

The course also emphasised on consent for euthanasia. Owners under the age of 18 are not allowed to give consent for euthanise under any circumstance. Owners over the age of 18, however, may give consent. Additionally, especially in the event of an emergency, a police constable is able to give consent to euthanising the horse if confident in the vets reasons. This maybe necessary in the event of an accident where the owner is not present at the site. A veterinarian will have to have written consent to euthanise a horse, this can be through an official consent form which the vet could obtain from their practice, or in an emergency, a consent form can be created on paper with the owners name, horses name, reason for euthanising and a witness’ name and signature. This may be important for the insurance company.

In a next section of the course, the methods of euthanasia was covered, of which there are two, Free bullet of lethal injection. The slideshow advised on the appropriate safety measures a licensed vet should take if using this method. The lethal injection method was then discussed. The injection is administered intravenously via a catheter which caused the following: a loss of consciousness, cease of respiration, a depress in cardiac contraction and irreversible anaesthesia. The ideal rate of administration of the injection would be over 10-15 seconds and cause the heart to stop “moments after the drug has been administered to the brain” (Knottenbelt D C et al, 1994). A longer period may cause the drug to work slower and less effectively which may cause owners some distress. It is also suggested that the horse can be sedated pre-administration to calm the horse, which would aid in the drug working effectively.

I found the questions at the end of each section within the slide show an effective way of remembering the information learnt and kept me engaged in the course content. The questions were multiple choice.

As Dechra are producers of the product Somulose, the lethal injection drug, there was then a section on the characteristics of the product. The active ingredients are quinalbarbitone and Cinchocaine hydrochloride (400 mg/ml and 25 mg/ml respectively). The dosage of Somulose should be 1 ml per 10kg of body weight. For example a 600kg horse, an dose of

60 ml of Somulose should be administered. Being a lethal drug, it is classified as a POM- V Schedule 2 controlled drug, which therefore require each use to be documented on a controlled drug register. The drug should be stored out of direct sunlight in its packaging in temperatures under 30oC. In freezing temperatures, Somulose can crystallise and from a sediment. If this happens the drug should not be used and a fresh one should be administered.

In conclusion the course covers the main aspect to considers surrounding euthanasia and the characteristics of the lethal injection. Consent and carcass disposal were also covered. The course was equivalent to 30 minutes Core Professional Development, for which you receive a certificate from the Dechra Academy.

Knottbelt D C et al: Vet record 1994, 3-19-324

Reflective Piece

On starting the BioveterinaryScience degree at Writtle University college, it was clear that maths and chemistry are to be prominent through the duration of the course with first year modules such as Essential Laboratory Techniques and Fundamentals of Bioveterinary Science. With this considered, I know that my confidence in areas of mathematics is not strong as certain topics, such as quadratics and statistics, haven’t been used since doing my GCSE’s in 2013 and 2014.For me, the most prominent issue with chemistry, questions involving long, complex calculations can also be intimidating: this can then lead to mistakes being made out of feeling nervous. A consequence of this can have a possible effect on future modules such as microbiology and nutrition in the second year of the course and well as, more predominantly, negatively affecting the performance of upcoming assignments. Having a lack in confidence may also decrease my performance and participation in group activities, with a further effect of a poor outcome in the task. 

 

I find that in learning and revising theoretical concepts in chemistry, making posters then doing practice questions was the most efficient way to remember the content. Using posters as a visual aid to learning can be seen to be encouraged by most teachers and educational institutions: cognitive science supports the visual display of information as useful for student learning; in particular, dual coding theory describes the benefit of both verbal and non-verbal processes for key components of cognition (Clark and Paivio, 1991). Additionally, I know that using practical sessions to back up topics that I learn in theory lectures helps me to understand and internalise the process. This has been implemented already on the course when learning to make solutions in the most recent sessions of Essential Laboratory Techniques: after doing the calculations on paper in the theory lesson, we had a practical sessions using the methods of calculations to make, for example, glucose solutions. The practical session on making solutions helped consolidate the method used in the theory lesson. This kind of learning can be seen to be called action learning, where using a physical action of the learner can positively reinforce a topic, (Johnson c. and Spicer D.P.,2006). 

 

In realising that I benefit from consolidating topics in chemistry using posters, I can make posters based on the content of the lecture sessions and use those as revision. Another learning mechanism I could explore in the future may be making flash cards of key points and using learning platforms such as Quizlet to test myself routinely, not just to mass study before an exam or assignment, this learning mechanism can also be known as spacing. A recent survey of college students found that the majority seemed to be aware that spaced study benefits learning (Morehead et al, 2016). It may also be useful to supplement my learning with chemistry related maths questions from Chemistry for the Biosciences as it has self check questions throughout the chapter which will help to understand fundamental concepts applicable to the course(Crowe, J. and Bradshaw T., 2014). Writtle also offers learner support sessions on maths topics which, if I am having difficulties, I can go to if independent study is not enough. Furthermore, I can seek help from the course tutor in the lesson or outside of the lesson: this can include asking them to go back over. By putting into practice these methods, I aim to become more confident when presented with a mathematical or chemistry related questions as well as finding a sustainable method of revision. A final method I could use to enhance my mathematic skills is to work in a  small group to understand topics in the library or study rooms. This would help reduce the pressure of a classroom environment and can be seen to be useful in many studies including one by Erna Yackel, who looked into small groups being a source of learning opportunities in maths (Yackel E. et al, 1991).

 

Reference list 

Clark, JM. and Paivio, A. (1991). Dual coding theory and education. Educational Psychology Review, 3(3): 149-170. 

Crowe, J. and Bradshaw, T. (2014). Chemistry for the Biosciences: The Essential Concepts. 

Johnson C. and Spicer D.P, (2006) “A case study of action learning in an MBA program”, Education + Training, Vol. 48 Issue: 1, pp.39-54, https://doi.org/10.1108/0040091061064572

Morehead, K., Rhodes, M. G., & DeLozier, S. (2016). Instructor and student knowledge of study strategies. Memory, 24, 257-271

Yackel E., Cobb P. and Wood T.(1991). Journal for Research in Mathematics Education (Vol. 22, No. 5), pp. 390-408