Comparative Anti-inflammatory Effects of Insulin and Flunixin on Acute-Phase Responses and Cardiovascular Biomarkers During Inflammatory Phase in Miniature Donkeys

Effect of experimentally induced endotoxaemia and meloxicam administration on the haemostatic system in donkeys

BACKGROUND

Endotoxaemia is a common condition in equids, frequently accompanied by alterations in haemostasis. Non-steroidal anti-inflammatory drugs, such as meloxicam, have been proven to alleviate some signs of endotoxaemia in donkeys. Neither the haemostatic response to induced endotoxaemia nor the effect of meloxicam in this regard have been described in donkeys.

OBJECTIVES

(a) To characterise the haemostatic changes in response to induced endotoxaemia in healthy donkeys, and (b) to assess the effect of meloxicam in these animals.

STUDY DESIGN

In vivo experiments.

METHODS

Endotoxaemia was induced by LPS (20 ng/kg) infusion in six healthy adult Andalusian donkeys. All animals randomly received either an IV bolus of saline solution (untreated group) or meloxicam (0.6 mg/kg) after LPS infusion (PLI), with a 1-month washout period between trials. Samples were collected at -30, 0, 30, 60, 90, 120, 180 and 360 min PLI for clotting times, antithrombin III, anti-Xa activities, platelet and fibrinogen concentrations; and at -30, 90, 180 and 360 min PLI for viscoelastography (Sonoclot).

RESULTS

LPS caused prothrombotic-specific viscoelastographic changes (short activated clot time and elongated clot rate formation) and lower antithrombin III activities compared with reference range for this species. Prolonged prothrombin times were also seen at late timepoints in the experiment. Meloxicam administration resulted in no significant differences between groups.

MAIN LIMITATIONS

Short sampling duration, only Andalusian donkeys.

CONCLUSIONS

Acute endotoxaemia induced hypercoagulability and initial signs of a consumptive coagulopathy in donkeys. Despite a more prolonged increase in anti-Xa activity, meloxicam did not ameliorate most of these haemostatic changes.

Hemodynamic Response to Lipopolysaccharide Infusion and Effect of Meloxicam Administration on Cardiac Function in Donkeys

Systemic inflammatory response syndrome (SIRS) in donkeys is observed to be secondary to colic, diarrhea or pleuropneumonia, among other disorders. Horses with SIRS develop secondary disturbances such as hyperlipemia, laminitis, disseminated intravascular coagulopathy, and hemodynamic and cardiac derangements, which impair their prognosis and increase the mortality rate. In donkeys, no information is available on the effect of experimentally induced endotoxemia in the cardiovascular system. Acute experimental endotoxemia was induced by lipopolysaccharide (LPS) infusion in six healthy adult non-pregnant jennies. Physical signs, arterial (systolic, diastolic and mean) and central venous pressure were monitored during 360 min. Cardiac troponin I (cTnI) concentrations were measured in blood samples, and echocardiography was performed. LPS infusion caused an increase in cTnI, hypotension and diminution of central venous pressure, cardiac dysfunction, with a decrease in stroke volume (SV), cardiac output (CO) and cardiac index, and impairment of ultrasonographic ventricular function parameters. Intravenous meloxicam administration prevented the cTnI increase, hypotension, diminution of SV and CO, and changes in ultrasonographic parameters related to ventricular dysfunction. Thus, meloxicam could be proposed as an effective therapeutical option to control the hemodynamic and cardiac derangements observed in donkeys with SIRS.

Preliminary study on heart response and locomotor parameters in Donkeys (Equus asinus) during exercise using fitness tracker (Equimetre)

The welfare of donkeys remains a compelling subject for researchers, with limited literature available on the response of the donkey cardiovascular system during strenuous exercise. The study aimed to address two primary objectives. Firstly, to assess the reliability of wearable devices in detecting heart rate (HR) and ECG readings. Secondly, to determine HR, locomotor and cardiac troponin 1 (cTnI) levels in donkeys during exercise. A total of seven donkeys were outfitted with two systems for ECG measurements, namely Equimetre and the Standard base apex, to enable a comparison between the two. Additionally, fifteen apparently healthy donkeys equipped with Equimetre were divided into two groups: the race group (R), consisting of donkeys trained for racing, and the non-race group (NR), comprising donkeys used for regular riding. The results indicated a level of agreement between the two devices in intervals R-R (P =  < 0.0001), S-T (P = 0.0002), Q-T(P = 0.0003), P-R (P = 0.0037), segment P-R (P = 0.0023) and HR (P =  < 0.0001) at rest. This suggested that Equimetre can provide a level of accepted ECG reading in donkey. No significant difference in heart response and locomotor parameters between donkey groups, although this finding needs further studies to verify it and to understand the dynamics of donkey. This study demonstrates the feasibility of Equimetre in detection HR and present initial data of heart response and locomotor in donkeys during exercise.

Pain Assessment and Acute Phase Response in Donkeys Submitted to Inguinal Orchiectomy

In most animals, pain can compromise physiological functions and delay healing so, rapid detection of pain through behavior and inflammatory reaction with biomarkers are necessary. This study aimed to evaluate pain, physiological variations and Acute Phase Proteins (APP) in donkeys undergoing orchiectomy technique by inguinal access. For this research, 15 male northeastern donkeys kept in extensive management were selected, with a mean age of 4.5±3.1 years. All animals had the same anesthetic protocol, using dissociative anesthesia and local block with lidocaine, followed by orchiectomy by inguinal access. Due to their predisposition to complications, the inguinal technique is the most indicated to minimize complications and excessive inflammation in donkeys' orchiectomy, the donkeys were evaluated regarding behavioral assessment of pain, hematological parameters, APP and the surgical wound, during 0 hour, 24 hours, 48 hours and 72 hours. As for the physiological parameters and APP, no significant differences were observed between times, due to the use of nonsteroidal antiinflammatory drugs. In the macroscopic evaluation of the surgical wound, it was observed that there were no significant differences between the times, with animals presenting mean scores of 1.8±0.414, in 48 hours 1.6 ± 0.507, and in 72 hours 1.6 ± 0.507. Most animals had mild to moderate edema in the scrotum and foreskin regions. As for pain assessment, the average scores were between 2 and 3, representing mild and moderate pain, not requiring intervention. However, further research is needed to elucidate the behavior of PFAs in the face of variables and the creation of new pain scales for animals raised in an extensive system.

Donkey Heart Rate and Heart Rate Variability: A Scoping Review

Heart rate (HR) and heart rate variability (HRV) are commonly used physiological measures in animals. While several studies exist on horse HRV, less information is available for donkeys. This scoping review aims to understand the extent and type of published evidence on donkey HR and HRV, their clinical and research applications, the devices used, and the analysis performed. Only quantitative primary studies published in English were considered. Four different databases were queried through the Web of Science platform, with additional evidence identified by citation chasing. After a two-stage screening phase, data were extracted considering study and population characteristics, information on HR/HRV analysis, and applications. The majority of the 87 included articles (about 80%) concerned a sample size of up to 20 individuals and were published since 2011 (about 65%). Forty-one articles employed an electronic device for signal acquisition (mainly electrocardiographs and heart rate monitors), yet only two articles reported HRV parameters. The literature on donkey HRV is lacking, and this gap can be filled by gaining knowledge on donkey characteristics and finding useful tools for welfare assessment. Comparison with what is known about the horse allows a discussion of the technical and interpretative difficulties that can be encountered with donkeys.

Bixin attenuates mechanical allodynia, anxious and depressive-like behaviors associated with experimental diabetes counteracting oxidative stress and glycated hemoglobin

Neuropathic pain, depression, and anxiety are common comorbidities in diabetic patients, whose pathophysiology involves hyperglycemia-induced increased oxidative stress. Bixin (BIX), an apocarotenoid extracted from the seeds of Bixa orellana, has been used in traditional medicine to treat diabetes and has been recognized by its antioxidant profile. We aimed to investigate the effect of the BIX over the mechanical allodynia, depressive, and anxious-like behaviors associated with experimental diabetes, along with its involved mechanisms. Streptozotocin-induced diabetic rats were treated for 17 days (starting 14 days after diabetes induction) with the corresponding vehicle, BIX (10, 30 or 90 mg/kg; p.o), or INS (6 IU; s.c.). Mechanical allodynia, depressive, and anxious-like behavior were assessed by electronic Von Frey, forced swimming, and elevated plus-maze tests, respectively. Locomotor activity was assessed by the open field test. Blood glycated hemoglobin (HbA1) and the levels of lipid peroxidation (LPO) and reduced glutathione (GSH) were evaluated on the hippocampus, pre-frontal cortex, lumbar spinal cord, and sciatic nerve. Diabetic animals developed mechanical allodynia, depressive and anxious-like behavior, increased plasma HbA1, increased LPO, and decreased GSH levels in tissues analyzed. Repeated BIX-treatment (at all tested doses) significantly attenuated mechanical allodynia, the depressive (30 and 90 mg/kg) and, anxious-like behaviors (all doses) in diabetic rats, without changing the locomotor performance. BIX (at all tested doses) restored the oxidative parameters in tissues analyzed and reduced the plasma HbA1. Thereby, bixin may represent an alternative for the treatment of comorbidities associated with diabetes, counteracting oxidative stress and plasma HbA1.

Application of α2 -adrenergic agonists combined with anesthetics and their implication in pulmonary intravascular macrophages-insulted pulmonary edema and hypoxemia in ruminants

Alpha₂ -adrenergic agonists have been implicated in the development of pulmonary edema (PE) and sustained hypoxemia that lead to life-threatening pulmonary distress in ruminants, especially with sensitive and compromised animals. Recently, there is limited understanding of exact mechanism underlying pulmonary alterations associated with α₂ -adrenergic agonist administration. Ruminants have a rich population of pulmonary intravascular macrophages (PIMs) in the pulmonary circulation, which may be involved in the development of pulmonary alveolo-capillary barrier damage. Hence, the central thesis of this review is overviewing the literatures regarding the systemic use of α₂ -adrenergic agonists in domestic ruminants, focusing on their pulmonary side effects, especially on the influence of PIMs on the lung. At this moment, further studies are needed to provide a clear emphasis and better understanding of the potential role of PIMs in the lung pathophysiology associated with α₂ -adrenergic agonists. These preliminary studies would be potentially to develop future medications and intervention targets that may be helpful to alleviate or prevent the critical striking pulmonary effects, and thereby improving the safety of α₂ -agonist application in ruminants.

Reference intervals of acute phase proteins in healthy Andalusian donkeys and response to experimentally induced endotoxemia

BACKGROUND

Assessment of acute phase proteins (APPs) may allow prompt detection of diseases in donkeys, that otherwise may be missed because of the stoic behavior of donkeys. Reference intervals (RIs) of APPs measured using immunoassays and a comparison of the response of these biomarkers to a controlled inflammatory insult are lacking in donkeys.

OBJECTIVES

(a) To describe the RIs for APPs in healthy Andalusian donkeys, (b) to study the effects of sex and age on APPs, and (c) to assess the early response of APPs to experimentally induced endotoxemia.

ANIMALS

Seventy-three healthy Andalusian donkeys (67 for RIs and 6 for endotoxemia).

METHODS

Serum amyloid A (SAA), haptoglobin (Hp), C-reactive protein (CRP), ceruloplasmin (Cp), α1-acid glycoprotein (AGP), procalcitonin (PCT), ferritin (Ft), and fibrinogen (Fb) RIs were determined. Endotoxemia was induced and samples for APP determination were obtained at regular intervals for 4 hours.

RESULTS

The RIs in Andalusian donkeys were: SAA (0.1-0.6 mg/L), Hp (75-2261 mg/L), CRP (1.3-7.0 mg/L), Cp (0-745 mg/L), AGP (0-884 mg/L), PCT (0-504 pg/mL), Ft (26.9-31.8 μg/L), and Fb (115-466 mg/dL). Concentrations of SAA were higher (P < .05) in jacks. Donkeys <5 years old had higher Cp, AGP, and PCT compared to older donkeys. Concentrations of SAA and Hp were significantly increased in endotoxemic donkeys from 2 hours postinduction.

CONCLUSIONS AND CLINICAL IMPORTANCE

We illustrated the importance of using species-specific RIs for APPs in donkeys and the effect of age and sex on APP concentrations. Concentrations of SAA and Hp appear to be the most useful biomarkers in donkeys in the early stages of endotoxemia.