Assessing the Efficacy of Ventilation of Anesthetized Neonatal Calves Using a Laryngeal Mask Airway or Mask Resuscitator

Calves that have undergone a dystocia are often hypoxic and acidemic, which can result in reduced vigor and subsequent mortality. Methods of field resuscitation of apneic newborn calves are often ineffective and therefore underutilized. This proof-of-concept study aimed to determine the efficacy of the laryngeal mask airway (LMA) as well as the current industry standard method of ventilation, the McCulloch Calf Aspirator/ Resuscitator (MMR) for positive pressure ventilation of neonatal calves. Five LMA models of various sizes were first tested in cadaver heads to assess anatomical fit. Three LMA models in two sizes each were then tested in two anesthetized calves to determine the model best suited to ventilate calves. Next, the selected LMA and the MMR were both assessed for efficacy of ventilation. Six anesthetized calves had hypoventilation induced by administering alfaxalone intravenously. Calves were ventilated for 3 min with the LMA, allowed a brief washout period, then given a second administration of alfaxalone prior to ventilation with the MMR. Serial arterial blood gas analyses were performed prior to ventilation (baseline), at 1, 2, and 3 min during ventilation, and 1 min after ventilation had ceased. Success of ventilation was assessed by monitoring partial pressure of oxygen (PaO2), partial pressure of carbon dioxide (PaCO2), bicarbonate (HCO3-), pH, L-lactate, and hemoglobin saturation (SaO2) in arterial blood. A one-way ANOVA for repeated measures with Bonferroni correction was used to assess the efficacy of ventilation of each device compared to baseline. For the LMA, PaO2, SaO2, and pH were significantly higher than baseline throughout ventilation and PaCO2 was significantly lower than baseline at 1 min of ventilation. For the MMR, PaO2 and SaO2 were significantly higher and PaCO2 and HCO3- were significantly lower than baseline for 1 to 2 min of ventilation. This proof-of-concept study showed the LMA is an effective means of ventilating neonatal calves, as was the MMR

Host innate immune responses and microbiome profile of neonatal calves challenged with Cryptosporidium parvum and the effect of bovine colostrum supplementation

IntroductionCalves are highly susceptible to gastrointestinal infection with Cryptosporidium parvum (C. parvum), which can result in watery diarrhea and eventually death or impaired development. With little to no effective therapeutics, understanding the host’s microbiota and pathogen interaction at the mucosal immune system has been critical to identify and test novel control strategies.MethodsHerein, we used an experimental model of C. parvum challenge in neonatal calves to describe the clinical signs and histological and proteomic profiling of the mucosal innate immunity and microbiota shifts by metagenomics in the ileum and colon during cryptosporidiosis. Also, we investigated the impact of supplemental colostrum feeding on C. parvum infection.ResultsWe showed that C. parvum challenged calves experienced clinical signs including pyrexia and diarrhea 5 days post challenge. These calves showed ulcerative neutrophil ileitis with a proteomic signature driven by inflammatory effectors, including reactive oxygen species and myeloperoxidases. Colitis was also noticed with an aggravated mucin barrier depletion and incompletely filled goblet cells. The C. parvum challenged calves also displayed a pronounced dysbiosis with a high prevalence of Clostridium species (spp.) and number of exotoxins, adherence factors, and secretion systems related to Clostridium spp. and other enteropathogens, including Campylobacter spp., Escherichia sp., Shigella spp., and Listeria spp. Daily supplementation with a high-quality bovine colostrum product mitigated some of the clinical signs and modulated the gut immune response and concomitant microbiota to a pattern more similar to that of healthy unchallenged calves.DiscussionC. parvum infection in neonatal calves provoked severe diarrheic neutrophilic enterocolitis, perhaps augmented due to the lack of fully developed innate gut defenses. Colostrum supplementation showed limited effect mitigating diarrhea but demonstrated some clinical alleviation and specific modulatory influence on host gut immune responses and concomitant microbiota

Protocol for a systematic review of disease control strategies used to prevent infectious mortality and morbidity in pre-weaned beef calves

Beef Cattle Research Council, Results Driven Agriculture Research, and the University of Calgary Faculty of Veterinary MedicineIt is essential to optimize the production of calves in order to maximize economic returns to producers and the availability of feeder cattle and replacement stock for the industry. Morbidity and mortality in beef calves have negative impacts on beef operations and are associated with considerable economic damage (2,3). By implementing effective disease control strategies, morbidity and mortality caused by Bovine Respiratory Disease (BRD) and Neonatal Calf Diarrhea (NCD) may be reduced. Studies have shown that failed transfer of passive immunity (3–7), season of birth (8), herd size (2,3), assistance at calving (3,9), and purchasing adult cattle and using community pastures (10) are risk factors for morbidity and mortality in calves. Disease control strategies are an essential component of the health management of beef herds (11) and some preventive practices have shown financial benefits (12). Herd demographics and management practices alter the epidemiology of disease within the herd (13), with various strategies aiming to improve the animal environment, boost the immune system (14), and diminish animal exposure to potential pathogens (15). Risk factors associated with the multifactorial syndromes of BRD and NCD have been explored mainly in dairy calves (5–8), but there are a limited number of studies related to beef calves (16) and no efforts to summarize the available literature have been reported. A systematic review of the current scientific literature will be conducted focusing on colostrum management, vaccination strategies, biosecurity, biocontainment, metaphylactic use of antibiotics, and other strategies used to prevent mortality and morbidity caused by BRD and NCD in pre-weaned beef calves. To the best of our knowledge, there is no published systematic review on disease control strategies used in beef calves during the preweaning stage.Othe

Prevalence of and risk factors for equine glandular and squamous gastric disease in polo horses

The objectives of this study were to determine the prevalence rates and risk factors for equine glandular gastric disease (EGGD) and equine squamous gastric disease (ESGD) in a population of 63 polo horses in competition. The prevalence of EGGD grade ≥ 1 was 69% and EGGD ≥ 2 was 31%. The prevalence of ESGD grade ≥ 1 was 54% and grade ≥ 2 was 37%. The risk factors retained in the final multivariable models were years of experience in polo competition for EGGD grade ≥ 1 and for grade ≥ 2, with decreased experience being associated with EGGD and weekly exercise duration and non-steroidal anti-inflammatory drug (NSAID) use being associated with ESGD grade ≥ 1. Decreasing weekly exercise duration was the only risk factor associated with ESGD grade ≥ 2. Equine gastric disease was common in this population of polo horses and the amount of experience and weekly exercise duration were related to the risk of disease

Protocol for the systematic review of strategies used in beef cattle to prevent or control internal or external parasites

Funding for this project was obtained from the Beef Cattle Research Council (BCRC), Results Driven Agriculture Research (RDAR), and the University of Calgary Faculty of Veterinary Medicine (UCVM).This paper describes the protocol for a systematic review that will evaluate the following question: What strategies are most effective for the prevention or control of internal or external parasites in beef cattle herds? The overall objective of this systematic review is to critically assess and synthesize the current published knowledge on the aforementioned review question

High species diversity of trichostrongyle parasite communities within and between Western Canadian commercial and conservation bison herds revealed by nemabiome metabarcoding

Abstract Background Many trichostrongylid nematode species are reported to infect bison, some of which are major causes of disase and production loss in North American bison herds. However, there is little information on the species distribution and relative abundance of these parasites in either commercial or conservation herds. This is largely because trichostrongylid nematode species cannot be distinguished by visual microscopic examination of eggs present in feces. Consequently, we have applied ITS2 rDNA nemabiome metabarcoding to describe the trichostrongyle parasite species diversity in 58 bison production groups derived from 38 commercial North American plains bison (Bison bison bison) herds from across western Canada, and two bison conservation herds located in Elk Island National Park (EINP) [plains bison and wood bison (Bison bison athabascae)] and one in Grasslands National Park (GNP) (plains bison). Results We report much higher infection intensities and parasite species diversity in commercial bison herds than previously reported in beef cattle herds grazing similar latitudes. Predominant trichostrongyle parasite species in western Canadian commercial bison herds are those commonly associated with Canadian cattle, with Ostertagia ostertagi being the most abundant followed by Cooperia oncophora. Combined with high fecal egg counts in many herds, this is consistent with significant clinical and production-limiting gastrointestinal parasitism in western Canadian bison herds. However, Haemonchus placei was the most abundant species in five of the production groups. This is both surprising and important, as this highly pathogenic blood-feeding parasite has not been reported at such abundance, in any livestock species, at such northerly latitudes. The presence of Trichostrongylus axei as the most abundant parasite in four herds is also unusual, relative to cattle. There were striking differences in parasite communities between the EINP and commercial bison herds. Most notably, Orloffia bisonis was the predominant species in the wood bison herd despite being found at only low levels in all other herds surveyed. Conclusions This study represents the most comprehensive description of parasite communities in North American bison to date and illustrates the power of deep amplicon sequencing as a tool to study species diversity in gastrointestinal nematode communities