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1.
Res Vet Sci ; 170: 105180, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38359647

RESUMEN

Our objective was to assess potassium monopersulfate as a disinfectant used in footbath to control digital dermatitis (DD) in dairy cows. We hypothesized that a potassium monopersulfate solution would control DD. A 180-day randomized negative controlled trial was conducted in a 265-Holstein free-stall facility. Throughout the trial, foot bathing was performed bi-weekly using a split (left vs. right feet) footbath: one tub filled with 1% potassium monopersulfate (treatment), the other with tap water (control). Digital dermatitis lesions were scored during trimming chute examinations of the unwashed hind heels every 90 days using the modified M-scoring system. Digital dermatitis lesions were re-categorized into four variables: 1) inactive; 2) active; 3) any; 4) inactive or absence of DD lesions. Three longitudinal outcomes were characterized: risks of 1) developing a DD lesion; 2) reactivating an inactive DD lesion; 3) development of an inactive or the absence of the DD lesion. A generalized linear model was used to compare the variables and longitudinal outcomes between treated and control groups. Prevalence of active DD lesions increased from 12.5% to 39.9% between days 0 and 90. This significant increase in prevalence justified the discontinuation of the study on day 90 for ethical reasons. There was no statistical difference between treated and control groups for the first outcome (RR: 1.0; 95% CI: 0.62, 1.7), the second outcome (RR: 1.0; 95% CI: 0.62,-1.7); or the third outcome (RR: 0.88; 95% CI: 0.37, 2.1). A 1% potassium monopersulfate footbath solution appears ineffective to control DD in this study.


Asunto(s)
Enfermedades de los Bovinos , Dermatitis Digital , Enfermedades del Pie , Pezuñas y Garras , Compuestos de Potasio , Sulfatos , Femenino , Bovinos , Animales , Lactancia , Dermatitis Digital/tratamiento farmacológico , Dermatitis Digital/prevención & control , Dermatitis Digital/epidemiología , Enfermedades de los Bovinos/tratamiento farmacológico , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/epidemiología , Pezuñas y Garras/patología , Industria Lechera , Enfermedades del Pie/prevención & control , Enfermedades del Pie/veterinaria
2.
Biology (Basel) ; 13(1)2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38248469

RESUMEN

BACKGROUND: Glucosensing elements are widely distributed throughout the body and relay information about circulating glucose levels to the brain via the vagus nerve. However, while anatomical wiring has been established, little is known about the physiological role of the vagus nerve in glucosensing. The contribution of the vagus nerve to inflammation in the fetus is poorly understood. Increased glucose levels and inflammation act synergistically when causing organ injury, but their interplay remains incompletely understood. We hypothesized that vagotomy (Vx) will trigger a rise in systemic glucose levels and this will be enhanced during systemic and organ-specific inflammation. Efferent vagus nerve stimulation (VNS) should reverse this phenotype. METHODS: Near-term fetal sheep (n = 57) were surgically prepared using vascular catheters and ECG electrodes as the control and treatment groups (lipopolysaccharide (LPS), Vx + LPS, Vx + LPS + selective efferent VNS). The experiment was started 72 h postoperatively to allow for post-surgical recovery. Inflammation was induced with LPS bolus intravenously (LPS group, 400 ng/fetus/day for 2 days; n = 23). For the Vx + LPS group (n = 11), a bilateral cervical vagotomy was performed during surgery; of these n = 5 received double the LPS dose, LPS800. The Vx + LPS + efferent VNS group (n = 8) received cervical VNS probes bilaterally distal from Vx in eight animals. Efferent VNS was administered for 20 min on days 1 and 2 +/10 min around the LPS bolus. Fetal arterial blood samples were drawn on each postoperative day of recovery (-72 h, -48 h, and -24 h) as well as at the baseline and seven selected time points (3-54 h) to profile inflammation (ELISA IL-6, pg/mL), insulin (ELISA), blood gas, and metabolism (glucose). At 54 h post-LPS, a necropsy was performed, and the terminal ileum macrophages' CD11c (M1 phenotype) immunofluorescence was quantified to detect inflammation. The results are reported for p < 0.05 and for Spearman R2 > 0.1. The results are presented as the median (IQR). RESULTS: Across the treatment groups, blood gas and cardiovascular changes indicated mild septicemia. At 3 h in the LPS group, IL-6 peaked. That peak was decreased in the Vx + LPS400 group and doubled in the Vx + LPS800 group. The efferent VNS sped up the reduction in the inflammatory response profile over 54 h. The M1 macrophage activity was increased in the LPS and Vx + LPS800 groups only. The glucose and insulin concentrations in the Vx + LPS group were, respectively, 1.3-fold (throughout the experiment) and 2.3-fold higher vs. control (at 3 h). The efferent VNS normalized the glucose concentrations. CONCLUSIONS: The complete withdrawal of vagal innervation resulted in a 72-h delayed onset of a sustained increase in glucose for at least 54 h and intermittent hyperinsulinemia. Under the conditions of moderate fetal inflammation, this was related to higher levels of gut inflammation. The efferent VNS reduced the systemic inflammatory response as well as restored both the concentrations of glucose and the degree of terminal ileum inflammation, but not the insulin concentrations. Supporting our hypothesis, these findings revealed a novel regulatory, hormetic, role of the vagus nerve in the immunometabolic response to endotoxin in near-term fetuses.

3.
Can Vet J ; 64(8): 733-741, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37529384

RESUMEN

A 5-year-old wether was presented for an acute onset of loss of appetite and inability to urinate. Urethral urolithiasis causing urethral obstruction was diagnosed and a cystostomy catheter was placed. The wether continued to be unable to urinate through the urethra and further developed a perineal pseudodiverticulum. Diverticulectomy followed by a urethroplasty using porcine small intestinal submucosa was performed to relieve the obstruction. The wether developed a urethral stricture following urethroplasty and the owners refused a perineal urethroplasty. Cystourethrography, fluoroscopic-guided balloon dilations, and urethral stent placement were done to establish urethral patency. The wether developed tissue ingrowth through the stent, resulting in recurrent obstruction that necessitated placement of covered urethral stents. Key clinical message: Although obstructive uroliths usually carry a guarded prognosis in small ruminants, the use of novel interventional radiology techniques along with urethroplasty using a xenograft allowed a wether to achieve urethral patency and normal urinations.


Prise en charge d'un bouc présentant des urétrolithes osbtructifs, un pseudodiverticule urétral et une stricture par diverticulectomie, urétroplastie et placement d'un stent urétral. Un bouc castré de 5 ans a été présenté pour une perte aigüe d'appétit et une incapacité à uriner. Un calcul urétral provoquant une obstruction urinaire a été diagnostiquée et une sonde de cystotomie placée. Le bouc a continué d'être incapable d'uriner pas son urètre et a développé un pseudodiverticule périnéal. Une diverticulectomie suivie d'une urétroplastie utilisant de la sous-muqueuse d'intestin grêle de porc a été réalisée pour soulager l'obstruction. Le bouc a développé une stricture urétrale à la suite de l'urétroplastie et les propriétaires ont refusé une urétroplastie périnéale. Une cystourétrographie, des dilatations par ballonnets guidées par fluoroscopie ainsi que le placement d'un stent urétral ont été réalisés afin de résoudre l'obstruction urétrale. Le bouc a développé une réaction tissulaire envahissant la lumière du stent, entrainant ainsi une nouvelle obstruction et nécessitant la mise en place de stents urétraux couverts.Message clinique clé :Bien que les urolithes obstructifs aient généralement un pronostic réservé chez les petits ruminants, l'utilisation de nouvelles procédures provenant de la médecine interventionnelle associées à une urétroplastie utilisant une xénogreffe a permis d'obtenir une perméabilité de son urètre et des mictions normales chez ce bouc.(Traduit par les auteurs).


Asunto(s)
Enfermedades de las Cabras , Enfermedades de los Porcinos , Obstrucción Uretral , Estrechez Uretral , Masculino , Animales , Porcinos , Uretra/cirugía , Constricción Patológica/complicaciones , Constricción Patológica/veterinaria , Cabras , Estrechez Uretral/cirugía , Estrechez Uretral/veterinaria , Estrechez Uretral/etiología , Obstrucción Uretral/cirugía , Obstrucción Uretral/veterinaria
4.
J Am Vet Med Assoc ; 261(6): 852-857, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36884377

RESUMEN

OBJECTIVE: To evaluate the association between serum phosphorus concentration and the outcome of postpartum downer cows. ANIMALS: Postpartum downer dairy cows presented over a 22-year period. PROCEDURES: In this cross-sectional study (1994 to 2016), medical records of all postpartum downer cows presented to a referral large animal hospital were reviewed. The association between serum inorganic phosphorus concentration and survival was assessed using a multivariable logistic regression. RESULTS: 907 postpartum downer dairy cows were included and classified as hypophosphatemic (mild: > 2.25 to < 3.25 mg/dL, moderate: > 1.50 to ≤ 2.25 mg/dL, and severe: ≤ 1.50 mg/dL), normophosphatemic (≥ 3.25 and ≤ 8.76 mg/dL) or hyperphosphatemic (> 8.76 mg/dL). Hypophosphatemia was observed in 19.4% of the cows (n = 176). Of those, 54.5% (n = 96) were also hypocalcemic. Overall, 58.4% cows (n = 530) survived after hospitalization. Hypophosphatemia was not significantly associated with the outcome of postpartum downer cows (mild: OR = 1.0, 95% CI: 0.6 to 1.8; moderate: OR = 0.5, 95% CI: 0.2 to 1.1; severe: OR = 1.0, 95% CI: 0.4 to 2.4). CLINICAL RELEVANCE: Low serum phosphorus concentration was frequently observed with hypocalcemia and was not associated with the outcome of postpartum downer cows.


Asunto(s)
Fósforo , Periodo Posparto , Femenino , Bovinos , Animales , Estudios Transversales
5.
J Am Vet Med Assoc ; 261(2): 273-280, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36434763

RESUMEN

OBJECTIVE: To determine the prognostic value of lactate concentration measurements at admission in cattle with long-bone fractures. ANIMALS: 43 cattle with long-bone fractures between July 2016 and Dec 2018. PROCEDURES: In this prospective cohort study, lactate concentration was measured in systemic venous blood and locally in capillary blood sampled from the fractured and contralateral limbs of cattle and assessed for outcome prediction. The cutoff value was determined by maximizing the Youden index from receiver-operating characteristic curves. Multivariable logistic regression was employed to verify whether higher lactate concentrations compared with the cutoff value were an independent risk factor for poor outcomes at 30 days or 3 years after admission. RESULTS: Poor outcome was associated with higher capillary lactate concentration in the fractured limb (P < .001) and greater difference with systemic blood (P = .005). A cutoff value of lactate difference ≥ 2.4 mmol/L (sensitivity = 0.80; specificity = 0.965) between capillary lactate in the fractured limb and systemic blood was the best predictor of death ≤ 30 days after admission (P < .001). Multivariable analysis revealed that this cutoff value was an independent risk factor for 30-day and 3-year outcomes (P < .001). CLINICAL RELEVANCE: Admission blood lactate concentration difference ≥ 2.4 mmol/L between the fractured limb and systemic blood was a robust and independent predictor of outcome for cattle of the present report. Lactate metabolism is locally impaired in fractured limbs of nonsurviving or at higher complication risk cattle, which may help identify patients at high risk for poor outcomes.


Asunto(s)
Enfermedades de los Bovinos , Fracturas Óseas , Bovinos , Animales , Ácido Láctico , Estudios Prospectivos , Pronóstico , Curva ROC , Fracturas Óseas/complicaciones , Fracturas Óseas/veterinaria
6.
Can Vet J ; 63(9): 943-946, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36060489

RESUMEN

A 4-year-old recently castrated male alpaca was referred for preputial prolapse of 4 d duration. Clinical findings upon admission were a 5 cm edematous preputial prolapse with the exposed preputial epithelium ulcerated and slightly necrotic. Initial therapy included NSAIDs and local treatment. A severe local inflammatory reaction with a consequent paraphimosis occurred on the penis and prepuce presumptively secondary to the use of a common compound ointment (i.e., tetracycline, scarlet oil, and lanolin) 24 h after its application. Medical treatment and local debridement were unsuccessful in reducing the paraphimosis. The prolapse was successfully reduced by traction of the penis through a para-preputial incision under general anesthesia. The alpaca was discharged after 22 d in hospital. The alpaca is still in the herd 24 mo after discharge with no prolapse recurrence.


Traitement chirurgical d'un paraphimosis chez un alpaga castré secondaire à une avulsion p réputiale. Un alpaga mâle de 4 ans récemment castré a été référé pour un prolapsus préputial d'une durée de 4 jours. Les signes cliniques à l'admission étaient un prolapsus préputial oedémateux de 5 cm avec l'épithélium préputial exposé ulcéré et légèrement nécrotique. Le traitement initial comprenait des AINS et un traitement local. Une réaction inflammatoire locale sévère avec un paraphimosis conséquent s'est produite sur le pénis et le prépuce, vraisemblablement secondaire à l'utilisation d'une pommade composée conventionnelle (i.e. tétracycline, huile scarlet et lanoline) 24 heures après son application. Le traitement médical et le débridement local n'ont pas réussi à réduire le paraphimosis. Le prolapsus a été réduit avec succès par traction du pénis à travers une incision parapréputiale sous anesthésie générale. L'alpaga est sorti après 22 jours d'hospitalisation. L'alpaga est toujours dans le troupeau 24 mois après sa sortie sans récidive de prolapsus.(Traduit par Dr Serge Messier).


Asunto(s)
Camélidos del Nuevo Mundo , Parafimosis , Herida Quirúrgica , Animales , Masculino , Parafimosis/cirugía , Parafimosis/veterinaria , Pene/cirugía , Herida Quirúrgica/veterinaria
7.
J Vet Intern Med ; 36(5): 1837-1842, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35906868

RESUMEN

BACKGROUND: Hemodilution of the cerebrospinal fluid (CSF) could confound interpretation of results. Accurately predicting total nucleated cells count (TNCC) and total protein concentration (TPC) attributable to hemodilution is difficult. OBJECTIVE: To determine the effects of hemodilution on TPC and TNCC in bovine CSF. METHODS: Retrospective review of CSF analysis results of downer dairy cows treated at Centre hospitalier universitaire vétérinaire between January 2006 and December 2014. Descriptive statistics were performed using 3 scenarios. RESULTS: Among the 235 samples included, red blood cell (RBC) count (RBCC) ranged from 0 to 869 220 RBC/µL (median = 6.6), TPC ranged from 0.04 to 6.51 g/L (median = 0.27), and TNCC ranged from 0 to 7500 cell/µL (median = 1.1). Among the 157 samples that had <30 RBC/µL (a threshold used in other species), TPC and TNCC varied between 0.13 and 1.06 g/L (median = 0.27) and between 0 and 31.4 cell/µL (median = 0.6), respectively. Eighty-four samples had TPC <0.25 g/L and TNCC ≤4.5 cell/µL. Among those 84 samples, RBCC varied between 0 and 1290 RBC/µL (median = 4.7). In 20 samples, TNCC was 0 with a variation in RBCC between 0 and 840 RBC/µL (median = 3.9). No strong correlations between RBCC and TNCC and TPC were found. CONCLUSIONS: A cutoff around 200 RBC/µL is proposed as clinically meaninful in bovine CSF. Results between 200 and 1290 RBC/µL are equivocal.


Asunto(s)
Líquido Cefalorraquídeo , Animales , Bovinos , Recuento de Células/veterinaria , Recuento de Eritrocitos/veterinaria , Femenino , Estudios Retrospectivos
8.
Cureus ; 14(12): e32632, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36660509

RESUMEN

Background The chronically instrumented non-anesthetized fetal sheep (CINAFS) model has been a mainstay of human fetal development research for the past 60 years. As a large "two for one" animal model, involving the instrumentation of the ewe and her fetus, the model poses challenges to implement de novo and maintain overtime at the highest standards of operating procedures to ensure ongoing performance. A common yet conventionally underreported issue researchers face is a high rate of animal loss. Here, we investigate what determines the success of the CINAFS model of human development. Methods We conducted a retrospective cohort analysis consisting of 82 experiments spanning the course of six years. Our team identified 10 variables that we anticipated were likely to influence the experimental outcome, such as the time of year, animal size, and surgical complexity. To evaluate the role of each variable in contributing to the success of the model, a binary logit regression analysis with a Fisher scoring optimization was fit to the data (SAS, V9 engine, release 3.8, SAS Institute, Cary, NC, USA). A higher predictive probability indicates a larger impact by the given variable on the outcome of the experiment. A Wald chi-squared analysis was run on the data to control for confounders and determine significance. Results The single variable identified in this study as determining the success of experiment outcomes using the CINAFS model is the experience level of the team. Conclusion The CINAFS model offers enormous potential to further our understanding of human fetal development and create interventional technologies related to fetal health. However, to improve experimental outcomes using the CINAFS model, stronger communication and training are needed. We discuss the implications of our findings for the successful implementation of this challenging yet scientifically advantageous animal model of human physiology.

9.
Vet Surg ; 50(7): 1398-1408, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34435675

RESUMEN

OBJECTIVE: To determine the stability bovine stifles stabilized with nylon or nitinol superelastic prostheses after transection of the cranial cruciate ligament (CCL). STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Stifles (n = 15) harvested from adult bovine cadavers. METHODS: The stifles were randomly assigned pairwise to a ligament reconstruction technique (n = 5): (1) and (2) Hamilton's technique using a prosthesis made of 24 nitinol strands (0.39 mm) braided at 40°or single 600-lb test nylon implant, and (3) nitinol prosthesis placed in femoral and tibial bone tunnels (bone-to-bone). Craniocaudal tibial translation at ±2000 N was applied to the tibia, and mediolateral angular displacement via measured under torsional tibial loading at ±60 Nm on three occasions: intact CCL, transected, and stabilized. Outcomes were evaluated with a mixed effect linear model for repeated measures. RESULTS: Bone-to-bone using nitinol was the only repair that decreased tibial translation after CCL transection (p = .001) with a 23% change magnitude compared with intact CCL. Hamilton was the only stabilization reestablishing angular displacement, similar to intact CCL (p = .109 and .134 for nitinol and nylon). Bone-to-bone nitinol stabilization decreased angular displacement after CCL-transection with an 8% change magnitude (p = .040) without returning to normal values. CONCLUSION: CCL replacement with nylon did restore joint stability. Nitinol prostheses passed through single femoral and tibial bone tunnels (bone-to-bone) were the only techniques reducing tibial translation. CLINICAL SIGNIFICANCE/IMPACT: Bone-to-bone stabilization with a nitinol prosthesis may be considered as an alternative to nylon for CCL replacement in cattle. These results provide evidence to justify clinical evaluation in cattle undergoing CCL replacement.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Enfermedades de los Bovinos , Aleaciones , Animales , Ligamento Cruzado Anterior , Lesiones del Ligamento Cruzado Anterior/veterinaria , Fenómenos Biomecánicos , Cadáver , Bovinos , Prótesis e Implantes , Rodilla de Cuadrúpedos/cirugía , Tibia
10.
J Vet Intern Med ; 35(5): 2534-2543, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34387390

RESUMEN

BACKGROUND: Downer cow syndrome, a common problem in dairy cattle, represents a diagnostic and therapeutic challenge for the attending veterinarian. Identifying prognostic indicators and assessing the odds of survival may improve the accuracy of the clinician's prognosis at the time of diagnosis. OBJECTIVE: To describe a population of downer dairy cows referred to a hospital and investigate predictors of outcome. ANIMALS: Recumbent adult dairy cows (cows unable or unwilling to stand without help) treated at a referral hospital. METHODS: Data at the time of admission were collected from medical records of downer dairy cows treated at the Centre Hospitalier Universitaire Vétérinaire between 1994 and 2016. Simple and multivariable logistic regression analyses were performed to assess the association of predictors with the outcome. RESULTS: Among 1318 cows included, 727 (55%) cows were discharged, and 591 (45%) cows died or were euthanized. Cows with longer time of recumbency before referral (odds ratio [OR] = 3.6), tachycardia (100-120 beats per minute [bpm], OR = 1.93; >120 bpm, OR = 2.92), tachypnea (OR = 1.76), hypothermia (OR = 2.08), anemia (OR = 3.30), neutropenia (OR = 1.7), high aspartate aminotransferase activity (500-1000 U/L, OR = 2.16; >1000 U/L, OR = 6.69), and increased serum creatinine concentration (OR = 1.75) had higher odds of nonsurvival. CONCLUSIONS AND CLINICAL IMPORTANCE: These findings may help the practitioner to consider treatment options and decide if referral is likely beneficial based on the odds of success. Early recognition of low chance of survival may facilitate an early decision for euthanasia.


Asunto(s)
Enfermedades de los Bovinos , Animales , Bovinos , Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/epidemiología , Femenino , Hospitales , Oportunidad Relativa , Pronóstico , Estudios Retrospectivos
11.
J Neurosci Methods ; 360: 109257, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34139266

RESUMEN

BACKGROUND: The chronically instrumented pregnant sheep has been used as a model of human fetal development and responses to pathophysiologic stimuli. This is due to the unique amenability of the unanesthetized fetal sheep to the surgical placement and maintenance of catheters and electrodes, allowing repetitive blood sampling, substance injection, recording of bioelectrical activity, application of electric stimulation, and in vivo organ imaging. Recently, there has been growing interest in the pleiotropic effects of vagus nerve stimulation (VNS) on various organ systems such as innate immunity and inflammation, and metabolism. There is no approach to study this in utero and corresponding physiological understanding is scarce. NEW METHOD: Based on our previous presentation of a stable chronically instrumented unanesthetized fetal sheep model, here we describe the surgical instrumentation procedure allowing successful implantation of a cervical uni- or bilateral VNS probe with or without vagotomy. RESULTS: In a cohort of 68 animals, we present the changes in blood gas, metabolic, and inflammatory markers during the postoperative period. We detail the design of a VNS probe which also allows recording from the fetal nerve. We also present an example of fetal vagus electroneurogram (VENG) recorded from the VNS probe and an analytical approach to the data. COMPARISON WITH EXISTING METHODS: This method represents the first implementation of fetal VENG/VNS in a large pregnant mammalian organism. CONCLUSIONS: This study describes a new surgical procedure allowing to record and manipulate chronically fetal vagus nerve activity in an animal model of human pregnancy.


Asunto(s)
Fenómenos Fisiológicos del Sistema Nervioso , Estimulación del Nervio Vago , Animales , Modelos Animales de Enfermedad , Femenino , Feto , Embarazo , Ovinos , Nervio Vago
12.
Mov Ecol ; 9(1): 23, 2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-33985582

RESUMEN

BACKGROUND: Migratory connectivity links the different populations across the full cycle and across the species range and may lead to differences in survival among populations. Studies on spatial and temporal migratory connectivity along migration routes are rare, especially for small migratory animals. METHODS: We used an automated radio-telemetry array to assess migratory connectivity en route and between early and later stages of the fall migration of the eastern populations of Swainson's Thrush, and to assess the variation of migration pace between consecutive detection from the different receiving stations along the migratory journey. We tracked 241 individuals from across eastern Canada to determine if populations were mixing around the Gulf of Mexico. We also tested the influence of tagging longitude, latitude and age on migration pace. RESULTS: Migration routes varied and converged towards the northeast coast of the Gulf of Mexico, but in this region, populations maintained finer-scale spatial structure. Migration pace increased as birds progressed south, independent of age and tagging site. CONCLUSIONS: We showed that for songbirds, migratory connectivity can be maintained at fine spatial scales despite the regional convergence of populations, highlighting the importance of detailed spatial tracking for identification of population specific migration routes. Overall, our study provides a portrait of migratory movements of eastern Swainson's Thrush and a framework for understanding spatial structure in migration routes for other species.

13.
J Dairy Sci ; 103(12): 11659-11675, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33069398

RESUMEN

Our first objective was to estimate the prevalence of foot lesions by type of milking system in dairy cows examined during regular hoof-trimming sessions between 2015 and 2018 in Québec dairy herds. A secondary objective was to describe the effect of day-to-day variation, cow, and herd characteristics on the prevalence of foot lesions. Data included 52,427 observations (on a cow during a specific trimming session) performed on 28,470 cows (≥2 yr old) from 355 herds. Only observations from trimming sessions in which ≥90% of the lactating herd was trimmed were considered. Lesions were recorded at the hoof level by 17 trained hoof trimmers between March 23, 2015, and July 10, 2018, using a computerized recording system. Hoof-level information was then matched with cow information and centralized at the Eastern Canada Dairy Herd Improvement. Foot lesions were classified into 6 categories: infectious, white line disease, heel erosion, ulcers, hemorrhages, and any type of foot lesions. Prevalence of each outcome was quantified using the marginal predicted mean probability estimated from a null generalized linear mixed model with a logit link, and accounted for clustering of observations by cow and by herd. Variance was partitioned to assess the variation in the probability of the outcomes attributable to each level of the data structure (day of exam, cow, and herd). Prevalence of a given foot lesion as function of milking system and of various explanatory variables (mean herd size, herd average daily production, breed of the cow, age of the cow at trimming, and year of the visit) was then estimated using a generalized linear mixed model. At least 1 foot lesion was observed in 29% of cows examined during regular trimming sessions in Québec from 2015 to 2018. Prevalence for any type of lesion was 27% for pipeline, 38% for robotic milking, and 41% for milking parlors. The highest prevalence of infectious lesions (mainly digital dermatitis) was observed in milking parlors and robotic systems, while the most prevalent lesions in pipeline were hemorrhages. Herd-level factors explained most of the disease probability for infectious diseases, heel erosion, and hemorrhages. Therefore, control of these diseases should be based on applying best herd-management practices. On the other hand, probabilities of white line disease and sole ulcers were mainly determined by cow-level characteristics.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades del Pie/veterinaria , Animales , Canadá , Bovinos , Industria Lechera , Dermatitis Digital/epidemiología , Femenino , Pie/patología , Hemorragia/veterinaria , Pezuñas y Garras/patología , Lactancia , Leche , Prevalencia , Quebec
14.
Ecol Evol ; 10(12): 5226-5239, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32607146

RESUMEN

In North America, the greatest and most sudden threat to hibernating bats is white-nose syndrome (WNS), which has caused massive declines in populations since 2006. Other determinants of bat dynamics, such as the climate, and the effect of reduction in the number of individuals sharing foraging space and summer roosting habitat may have an effect on population dynamics. We analyzed transect acoustic bat surveys conducted with ultrasonic detectors in 16 regions in Quebec, Canada, between 2000 and 2015. We used piecewise regression to describe changes in activity over time for each species and a meta-analytic approach to measure its association with the North Atlantic Oscillation (NAO). As expected, mouse-eared bat (Myotis spp.) activity sharply declined after the onset of WNS, down by 79% after 3 years. In contrast, big brown/silver-haired bat activity increased over the same period, possibly due to a release of competition. Hoary bats and red bats remained present, although their activity did not increase. Myotis activity was positively correlated with a one-year lag to the NAO index, associated with cold conditions in winter, but warm autumns. Big brown/silver-haired and hoary bats were also more active during NAO-positive years but without a lag. We conclude that combinations of threats may create rapid shifts in community compositions and that a more balanced research agenda that integrates a wider range of threats would help better understand and manage those changes.

16.
J Am Vet Med Assoc ; 256(7): 814-821, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32176576

RESUMEN

OBJECTIVE: To describe the clinical and clinicopathologic characteristics, treatment, and outcome for cattle that developed a retroperitoneal abscess (RA) following paralumbar fossa laparotomy (PFL). ANIMALS: 32 Holstein cows with RA. PROCEDURES: The record database of a veterinary teaching hospital was searched to identify cattle that were treated for an RA between January 1995 and March 2017. Cattle with an RA > 30 cm in diameter located 3.5 cm subjacent to the skin that had undergone a PFL < 3 months before examination for the RA were evaluated. Information extracted from the record of each cow included signalment; physical examination, clinicopathologic, and transabdominal ultrasonographic findings; treatments administered; and outcome. Milk production data were analyzed for the lactations before, during, and after RA treatment. RESULTS: Common physical examination findings were rumen hypomotility, anorexia, and fever, and common clinicopathologic findings were anemia and neutrophilia. Abdominal palpation per rectum and transabdominal ultrasonography facilitated RA diagnosis and identification of the optimal location for drainage. Thirty of 32 cows underwent surgical drainage of the RA and prolonged administration of systemic antimicrobials. Two cows were euthanized because of concurrent peritonitis, including 1 that underwent surgical RA drainage. Thirty cows were discharged from the hospital alive, and most returned to their previous level of milk production. CONCLUSIONS AND CLINICAL RELEVANCE: Although uncommon, RA should be suspected in cows that develop anorexia and fever within 3 months after PFL. Cows with RA often returned to their previous level of milk production, but treatment was generally prolonged and costly.


Asunto(s)
Absceso Abdominal/veterinaria , Absceso/veterinaria , Animales , Bovinos , Femenino , Lactancia , Laparotomía/veterinaria , Leche , Rumen
18.
J Vet Intern Med ; 34(2): 1018-1027, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32056284

RESUMEN

BACKGROUND: Abomasitis is a syndrome affecting young milk-fed calves. The current veterinary literature describes mainly its necropsy findings. OBJECTIVES: To describe the clinical presentation, complementary tests, treatments, and case-fatality rate of calves with a clinical diagnosis of abomasitis and to identify potential factors associated with outcome. METHODS: Observational retrospective cohort study (2006-2016). Review of the medical records of calves <3 months of age presented with abdominal and abomasal distension for <7 days that were clinically diagnosed with abomasitis at the Faculty of Veterinary Medicine of the Université de Montréal. A follow-up examination was conducted by telephone interview. ANIMALS: Twenty-three calves clinically diagnosed with abomasitis. RESULTS: Median age of presentation was 3 days (range, 0-62 days). The typical duration of the clinical course was <24 hours (15/23). On admission, the 2 most common clinical signs were anorexia (13/14) and positive succussion (13/14). Hyper-l-lactatemia (15/16) and increased γ-glutamyl-transferase activity (13/14) were the most common laboratory abnormalities. Hypoproteinemia (19/22) and a left shift (15/18) of the neutrophils also were observed. The short-term case-fatality rate was 52% (12/23). The clinical diagnosis was confirmed on all necropsied calves. Clostridium spp. and Escherichia coli were the most frequently isolated bacteria. Based on univariate statistical analysis, the surviving calves were significantly (P < .05) less hypothermic, less acidemic, less hyper-l-lactatemic, and had lower serum creatinine concentrations on admission than did the deceased calves. CONCLUSIONS AND CLINICAL IMPORTANCE: In our study, abomasitis was associated with a guarded prognosis.


Asunto(s)
Abomaso , Enfermedades de los Bovinos/diagnóstico , Gastritis/veterinaria , Animales , Animales Recién Nacidos , Bovinos , Enfermedades de los Bovinos/microbiología , Clostridium/aislamiento & purificación , Estudios de Cohortes , Escherichia coli/aislamiento & purificación , Femenino , Gastritis/diagnóstico , Masculino , Registros/veterinaria , Estudios Retrospectivos
19.
J Dairy Sci ; 103(4): 3381-3391, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32057431

RESUMEN

Digital dermatitis (DD) is a worldwide infectious disease of cattle that causes lameness, discomfort, and economic losses. The reference standard test to diagnose DD is visual observation in a trimming chute, which cannot be practically performed daily on dairy farms. Moreover, some lesion misclassification may occur using this standard diagnostic method. The possibility of misclassification makes the use of a trimming chute debatable as a perfect reference standard test. The objective of this study was, therefore, to assess the diagnostic accuracy of a commercial borescope and trimming chute exam. The accuracy (sensitivity and specificity) of the tests and DD prevalence were investigated using Bayesian latent class analyses. Our hypothesis was that a commercial borescope can be routinely used to diagnose DD in a milking parlor without previous feet cleaning. A cross-sectional study was performed in a freestall facility. The lesions were scored (M0, M1, M2, M3, M4, M4.1) in the milking parlor with a borescope, followed by an examination in the trimming chute 48 to 72 h after the borescope exam. A total of 870 hind feet were scored during 2 sessions of trimming chute exams and borescope exams in the milking parlor. The data were analyzed in 2 ways. First, data were dichotomized into DD lesions (M1, M2, M3, M4, M4.1) and absence of DD lesions (M0). Second, data were dichotomized into active DD lesions (M1, M2, M4.1) and inactive lesions (M0, M3, M4). A Bayesian latent class model allowing for conditional dependence between tests was used to estimate tests' accuracy, likelihood ratio, and DD prevalence. When the data were dichotomized into DD lesions (M1-M4.1) versus absence of DD (M0) lesions, the sensitivity and specificity of the borescope was 55% [95% credible interval (CrI) 40-71%] and 81% (95% CrI 75-88%). The sensitivity of trimming chute exams was 79% (95% CrI 68-88%), and specificity was 80% (95% CrI 71-89%). When the data were dichotomized into active lesions (M1, M2, M4.1) versus inactive lesions or absence of lesions (M3, M4, M0), the sensitivity and specificity of the borescope were, respectively, 32% (95% CrI 13-58%) and 91% (95% CrI 88-95%). The sensitivity and specificity of trimming chute exams were 91% (95% CrI 81-97%) and 81% (95% CrI 75-89%), respectively. In conclusion, it is possible to use the borescope in the milking parlor without cleaning the feet to monitor prevalence of DD lesions. However, an isolated borescope examination, especially for diagnosing active DD lesions, has low sensitivity for use as a surveillance method. For such use, the sensitivity could be improved by repeating the borescope exam on a regular basis.


Asunto(s)
Enfermedades de los Bovinos/diagnóstico , Diagnóstico por Imagen/instrumentación , Dermatitis Digital/diagnóstico , Enfermedades del Pie/veterinaria , Crianza de Animales Domésticos , Animales , Teorema de Bayes , Bovinos , Enfermedades de los Bovinos/epidemiología , Estudios Transversales , Industria Lechera/instrumentación , Industria Lechera/métodos , Dermatitis Digital/diagnóstico por imagen , Dermatitis Digital/epidemiología , Femenino , Enfermedades del Pie/diagnóstico por imagen , Enfermedades del Pie/epidemiología , Enfermedades del Pie/microbiología , Pezuñas y Garras/diagnóstico por imagen , Pezuñas y Garras/patología , Leche , Prevalencia , Sensibilidad y Especificidad
20.
Front Immunol ; 10: 1063, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31143190

RESUMEN

Neuroinflammation in utero may result in lifelong neurological disabilities. Astrocytes play a pivotal role in this process, but the mechanisms are poorly understood. No early postnatal treatment strategies exist to enhance neuroprotective potential of astrocytes. We hypothesized that agonism on α7 nicotinic acetylcholine receptor (α7nAChR) in fetal astrocytes will augment their neuroprotective transcriptome profile, while the inhibition of α7nAChR will achieve the opposite. Using an in vivo-in vitro model of developmental programming of neuroinflammation induced by lipopolysaccharide (LPS), we validated this hypothesis in primary fetal sheep astrocytes cultures re-exposed to LPS in the presence of a selective α7nAChR agonist or antagonist. Our RNAseq findings show that a pro-inflammatory astrocyte transcriptome phenotype acquired in vitro by LPS stimulation is reversed with α7nAChR agonistic stimulation. Conversely, α7nAChR inhibition potentiates the pro-inflammatory astrocytic transcriptome phenotype. Furthermore, we conducted a secondary transcriptome analysis against the identical α7nAChR experiments in fetal sheep primary microglia cultures. Similar to findings in fetal microglia, in fetal astrocytes we observed a memory effect of in vivo exposure to inflammation, expressed in a perturbation of the iron homeostasis signaling pathway (hemoxygenase 1, HMOX1), which persisted under pre-treatment with α7nAChR antagonist but was reversed with α7nAChR agonist. For both glia cell types, common pathways activated due to LPS included neuroinflammation signaling and NF-κB signaling in some, but not all comparisons. However, overall, the overlap on the level of signaling pathways was rather minimal. Astrocytes, not microglia-the primary immune cells of the brain, were characterized by unique inhibition patterns of STAT3 pathway due to agonistic stimulation of α7nAChR prior to LPS exposure. Lastly, we discuss the implications of our findings for fetal and postnatal brain development.


Asunto(s)
Astrocitos/fisiología , Encéfalo/metabolismo , Microglía/fisiología , Inflamación Neurogénica/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Animales , Encéfalo/patología , Bovinos , Células Cultivadas , Feto , Perfilación de la Expresión Génica , Lipopolisacáridos/inmunología , Neuroprotección , Factor de Transcripción STAT3/metabolismo , Transducción de Señal
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