CJVR - January 2024, Vol. 88, No. 1

Scientific

Articles

Development and validation of farm- and province-level swine flow simulation model using discrete events and Ontario swine farm and provincial input data

Maggie Henry, Wade McDonald, Robert M. Friendship, Amy L. Greer, Zvonimir Poljak (page 3)

Infectious disease events can cause disruptions in service-based and agricultural industries. The list of possible events is long and varies from the incursion or emergence of a reportable animal pathogen to the recently documented interruptions caused by the COVID-19 pandemic. There is a need to develop models that can determine the impact of pathogens and mitigation measures on populations that are not directly affected by the pathogen in the case of a reportable disease, particularly when the health and welfare of these populations could be affected due to resulting disruptions in trade and supply chains. The primary objective of this study was to develop a discrete-event simulation (DES) model of swine production, including pork processing, for scenarios without major disruptions, which could be scaled from the level of an individual farm to the entire province of Ontario, Canada. The secondary objective was to validate the developed simulation against observed farm- and province-level statistics. A weekly discrete-event simulation consisting of 3 connected areas (a sow farm, a pig farm, and abattoirs) was developed using AnyLogic modelling software. Using Mann-Whitney tests, model outputs representative of the standard industry statistics were compared to data from 6 individual farms separately, as well as to provincial data from Ontario. A scalable discrete-event simulation of the swine production system for typical scenarios was accomplished. The model outputs were consistent with individual farm and industry statistics. As such, the model can be used to simulate swine production at distinct levels and could be further modified to represent swine marketing in other provinces or internationally.

Ability of unsterilized recycled manure solids bedding to support growth of Klebsiella pneumoniae and Escherichia coli

Annie Fréchette, Mylène Généreux, Gilles Fecteau, Caroline Côté, Simon Dufour (page 12)

Although recycled manure solids (RMS) bedding is used on dairy farms, it could allow bacterial growth when contaminated by feces and thus increase the incidence of clinical mastitis in cows. The objective of this study was to describe bacterial growth in three different types of RMS bedding, as well as in sand, when samples were experimentally inoculated with Escherichia coli and Klebsiella pneumoniae. Two 3-day trials were conducted, during which treatments included inoculating bedding samples with E. coli and K. pneumoniae, as well as no inoculation. The trial was repeated 3 times for each bedding sample on each day. Samples were incubated at 15°C for 3 d and bacterial counts were measured every day. After inoculation, there was no significant K. pneumoniae or E. coli growth phase during the trial in those RMS samples that were prepared either in a container or in a heap. Recycled manure solids and sand samples prepared in a rotary drum, however, showed a similar active growth phase of K. pneumoniae during the first 24 h of the trial. Moreover, a significant E. coli growth phase was observed in the samples of sand bedding in the first 24 h. The 3 different types of RMS bedding samples did not react in a similar manner to coliform inoculation. No active growth phase was observed in bedding samples already containing a high bacterial concentration following inoculation with coliforms.

Metabolic response of broiler chickens to different doses of Enterococcus faecium ICIS 96 in the diet

Elena Kochkina, Alfia Andreeva, Alexey Torshkov, Veronika Dymova, Oleg Altynbekov, Mariia Sycheva (page 19)

The competitiveness and profitability of the poultry industry in market conditions are hampered by growing problems with the safety and quality of poultry meat. The use of targeted microbial preparations can assist in resolving these problems. Numerous studies of the properties of bacteria of the genus Enterococcus have shown their effectiveness in the practice of poultry farming. The objectives of this study were to identify the effect of various doses of Enterococcus faecium ICIS 96 added to the diet of broiler chickens on their metabolism and to evaluate the productive qualities of the chickens when different doses are used. The experiment was carried out on 72 Cobb-500 cross broiler chickens, divided into 3 groups. Chickens in the first group received a suspension of E. faecium ICIS 96 containing 1 × 108 cells in 1 mL of sterile saline, at a dose of 0.1 mL per 1 kg of live weight. The second group of chickens received a double dose of enterococcus, that is 0.2 mL of the suspension per 1 kg of live weight per day. The results demonstrated that 0.1 mL of a 1 × 108 per mL enterococcus culture suspension in the poultry diet per 1 kg of live weight per day intensified metabolism and increased the live weight of chickens after 40 d of treatment.

Retrospective study of perioperative antimicrobial use in horses undergoing elective laparoscopy at a single institution

Lucciana Recchi, Nicola Cribb, Nathalie Côté, Marie-Soleil Dubois, Judith Koenig, Alexander Valverde, Gabrielle Monteith (page 24)

Antimicrobial stewardship has shown significant development in recent years. Perioperative prophylaxis accounts for a substantial volume of antimicrobial use and is a field in which improvements can likely be made. The objective of this study was to evaluate practices associated with perioperative antimicrobial use in equine elective laparoscopy at a single institution over a 21-year period and to determine whether antimicrobial therapy influenced the occurrence of postoperative complications. Medical records of horses that underwent elective laparoscopy at a teaching hospital from January 2000 to September 2021 were reviewed. Data obtained included signalment, surgeon, type and duration of procedure, perioperative antimicrobial use, and intraoperative and postoperative complications. Exact univariate logistic regression was used to explore the association between possible risk factors and occurrence of postoperative complications, as well as the association between year of presentation and time of antimicrobial administration. Duration of surgery was log-transformed to meet assumption of normality, followed by analysis of variance (ANOVA) to compare mean surgery time per procedure and postoperative complications. Significance was set at P < 0.05. Sixty horses met the inclusion criteria. All horses received antimicrobial prophylaxis, but none received intraoperative redosing. Only 13 horses (26%) received antimicrobials within 60 min of the first incision. Time of administration improved with each year of the study (P = 0.005). Only 17 horses (28%) received antimicrobials for less than 24 h, but median duration of antimicrobial therapy was 1.25 d (range: 0.25 to 10 d). Antimicrobial use practices at this institution differed from general recommendations for optimal perioperative prophylaxis, which suggests that intervention is required.