Circulating oxidative stress and acute phase protein levels in horses infested with ticks.

Ticks have saliva rich in immunoregulatory molecules that interfere with the host's physiology in order to feed. This study aimed to evaluate the concentration of acute phase proteins and circulating oxidative stress in response to infestation by Amblyomma sculptum and Dermacentor nitens in two breed horses, Mangalarga Marchador and Breton Postier, to define resistance or susceptibility to ticks. Among the oxidative stress markers, we observed lower malondialdehyde and nitric oxide in horses with tick infestation, consequently not altering the antioxidant enzymes. Breton Postier with tick infestation showed a reduction in the ferric reducing ability of plasma (FRAP), which may be due to lower feeding of the host due to the stress caused by the infestation or even to sequestration of components induced by the tick during blood feeding. The alpha-1-antitrypsin, an acute phase protein, showed an increase in Mangalarga Marchador with tick infestation; curiously it is related to a protective action against tissue damage, pathogens and parasites. We could assume that Mangalarga Marchador showed a better response to ticks when compared to Breton Postier. However, it is still early to define the resistance or susceptibility to ticks, as we did not observe significant changes in most of the analyzed variables. Further studies are needed to understand the compounds and mechanisms of action of the tick saliva in the acute phase proteins and the possible relationships of oxidative stress in the host and the tick during blood feeding.

'Candidatus Mycoplasma Haemoalbiventris' and Tick-Borne Pathogens in Black-Eared Opossum (Didelphis aurita) from Southeastern Brazil.

The black-eared opossum (Didelphis aurita) is a South American synanthropic marsupial. The presence of opossums in domestic spaces is relevant in the One-Health context since they are hosts of pathogens and ectoparasites that may affect the health of domestic animals and humans. In this study, we aim to determine the occurrence of hemoplasmas and selected tick-borne pathogens in free-ranging black-eared opossums, along with their molecular characterization, hematological and biochemical evaluation and factors associated with infection, in the municipality of Viçosa, State of Minas Gerais, southeastern Brazil. Thirty black-eared opossums were trapped between March 2021 and June 2022. Ectoparasites were collected. Hematological and biochemical analyses were performed. DNA from EDTA-blood samples were analyzed by PCR and qPCR assays. By molecular analyses, 'Candidatus Mycoplasma haemoalbiventris' was the most prevalent hemoparasite (73.3%), followed by Hepatozoon sp. (22.2%). Significant differences were observed in the number of platelets, and in the concentration of protein and globulins in the animals infected by 'Ca. M. haemoalbiventris' when compared with the negative group. This is the first report of 'Ca. M. haemoalbiventris' infection in D. aurita.

Influence of Short and Medium Distance Road Transport on the Acute Phase Proteins in Horses.

Horse transport is a common practice and is usually associated as a cause of stress in animals, with consequences for their well-being. There are several of evidence that stress can increase an acute phase response. The aim of this study was to verify whether the road transport of horses over distances of 50 and 300 kilometers induces changes in the values of acute phase proteins. To do this, the serum SDS-PAGE was performed and the bands obtained were identified by mass spectrometry (MALDI-TOF). The blood samples were collected in tubes without anticoagulant to obtain the serum, and the evaluations occurred before the road transportation (T0), immediately after the journey (T1), six hours later (T2), and 24 hours (T3), 48 hours (T4), 72 hours (T5), 96 hours (T6), 120 hours (T7) and 144 hours (T8) after the end of the trip. All analyzes were performed using the Minitab 17 statistical package, and significance was considered when P<0.05. The APPs found through SDS-PAGE and properly identified were α2-macroglobulin, ceruloplasmin, transferrin, albumin, α1-antitrypsin, haptoglobin, apolipoprotein alpha 1, and α1-acid glycoprotein. No differences were observed in the concentration values between 50 and 300 km or between the moments after each route. The distances covered with the horses were not challenging enough to provoke an acute phase response reflected in changes in APPs.

Profile of Acute-Phase Proteins of Horses Submitted to Low-Level Show Jumping Classes.

The objective of this study was to evaluate the serum proteinogram, identifying and quantifying the acute-phase proteins (APPs) of horses used in show jumping activity with obstacles of a meter in height. As it is an equestrian sport that involves high intensity and excessive impact, the possibility of injury is relevant. The serum of 10 horses was evaluated in a competition for beginners. The material was collected at rest (T0), immediately after exercise (T1), 30 minutes after the effort (T2), 1 hour after the effort (T3), and 24 hours after the effort. Acute-phase proteins were separated by polyacrylamide gel electrophoresis and their concentrations determined by computerized densitometry. Protein identification was performed using mass spectrometry. The data were evaluated using analysis of variance for repeated measures, considering the level of significance of P < .05. Eight APPs were identified: α2-macroglobulin (α2-macro), ceruloplasmin (Cp), transferrin (Trf), albumin (Alb), α1-antitrypsin (α1-atp), haptoglobin (Hp), acid glycoprotein (AGP), and apolipoprotein A1 (Apo A1). There was a difference in Cp, AGP, and Apo A1 between moments. As the other proteins were not influenced by exercise, they were established as a valuable resource in the monitoring of inflammatory processes and an important complementary element in controlling the impact of training on the animals, thus guaranteeing their welfare.

Acute-Phase Proteins of Healthy Horses and Horses Naturally Affected by Colic Syndrome.

The purpose of this study was to evaluate and compare the serum proteinogram, identifying and quantifying the acute-phase proteins (APPs) of healthy horses and those naturally affected by colic syndrome. Blood samples were collected from 9 healthy horses and 17 horses with clinical (G1) or surgical (G2) colic at the time of arrival at the veterinary hospital (M0) and 24 (M1), 48 (M2), and 72 (M3) hours after the initiation of treatment. The APPs were separated by polyacrylamide gel electrophoresis (SDS-PAGE), and their concentrations were determined by computerized densitometry. Protein identification was performed using matrix assisted laser desorption/ionization-time of flight mass spectrometry. Nine APPs were identified: α2-macroglobulin, ceruloplasmin, transferrin, albumin, α1-antitrypsin, haptoglobin, α1-acid glycoprotein, apolipoprotein A1, and serum amyloid A. Ceruloplasmin (Cp) presented an elevation at M0 in G2 in relation to G1 and the control group (CG). Serum amyloid A (SAA) presented an elevation with a difference at M3 in G1 and G2, compared with CG. In the comparison between the time points within each group (G1 and G2), there was an increase in SAA in G2 with a difference at M1, M2, and M3. Cp and SAA were suitable for evaluating the acute-phase response in horses with colic. Cp was an indicator of colic with surgical resolution. SAA presented favorable behavior for its use as a biomarker to establish the prognosis in horses with colic. The serial measurement of these proteins was useful in differentiating the clinical or surgical treatment and prognosis of horses with this disorder.