Immune components present in mammary secretions are reviewed. In swine, the histological structure of the placenta prevents in utero transfer of immunoglobulins and mammary secretions are the sole source of maternal antibody for the neonate. In addition to immunoglobulins, porcine mammary secretions contain significant numbers of maternal cells of various types that may contribute to neonatal immunity, including phagocytes (neutrophils and macrophages), lymphocytes (B and T cells), and epithelial cells. Immunomodulating and/or antimicrobial substances, including lactoferrin, lysozyme, lactoperoxidase, and cytokines, are also present in mammary secretions and may contribute to the protection of the neonate. While the role of immunoglobulins in mammary secretions is well understood, the contribution of cellular components and non-specific immune factors to neonatal immunity remains to be defined.

Immune components in porcine mammary secretions.

A world dictionary of livestock breeds, types and varieties.

Immune modulation and modulators in Heligmosomoides polygyrus infection.

SummaryBackground
Certain individuals appear to be predisposed to recurrent pasture-associated laminitis. Previous studies have predominantly investigated risk factors only after disease occurrence.

Objectives
To investigate risk factors for pasture-associated laminitis prior to disease occurrence.

Study design
Prospective cohort study.

Methods
Non-laminitic ponies aged ≥7 years were recruited. Body condition score (BCS), height, weight, crest height and thickness were measured and an overnight dexamethasone suppression test performed. Plasma or serum adiponectin, leptin, triglyceride, basal insulin, insulin post-dexamethasone, insulin-like growth factor 1 (IGF-1), IGF binding protein 1 (IGFBP-1), IGFBP-3, C-reactive protein, von Willebrand's factor, soluble E-selectin and P-selectin concentrations were assayed. Follow-up data were obtained from owners annually for 3 years to ascertain occurrences of veterinarian-diagnosed pasture-associated laminitis. Data were analysed by multivariate logistic regression. Receiver operating characteristic (ROC) curves analysis was performed for significant risk factors and cut-off values determined.

Results
A total of 446 animals with a median (interquartile range) age of 15 (10–20) years were recruited. Of these, 50.4% were mares and 49.6% were geldings. The most common breeds were Welsh (36.4%), Shetland (17.0%) and cob (9.4%). Overall, 72.2% of animals were overweight/obese (BCS 7–9/9), 27.3% were of ideal weight (BCS 4–6/9) and 0.5% were underweight (BCS 1–3/9). After 1, 2 and 3 years, respectively, 18 (4.0%), 30 (6.7%) and 44 (9.9%) animals were reported to have had laminitis. Plasma adiponectin, and serum basal (insulin) and (insulin) post-dexamethasone levels were significantly (P ≤ 0.05) associated with laminitis occurrence cumulatively after 1, 2 and 3 years. Use of the area under the ROC curves to distinguish animals that did and did not develop laminitis showed good (basal [insulin] after 1 year), fair (all others) or poor ([insulin] post-dexamethasone) levels of accuracy.

Main limitations
Animals were evaluated at a single time point and biomarkers were assayed using single assays.

Conclusions
Risk factors for future laminitis prior to disease occurrence include low plasma adiponectin and high serum basal insulin or insulin post-dexamethasone concentrations.

Prospective cohort study evaluating risk factors for the development of pasture‐associated laminitis in the United Kingdom

Characterization of peripheral blood and pulmonary leukocyte function in healthy foals.

Acute phase protein concentrations after limited distance and long distance endurance rides in horses

Summary Reasons for performing study: Changes in serum levels of acute phase proteins (APPs) reflect the acute phase reaction, a rapid and nonspecific response to any tissue damage. Serum amyloidA(SAA) is the mainAPPin horses, which increases in various diseases, surgical injuries and after long distance endurance rides; however, this nonspecific parameter has not been investigated as an indicator of subclinical disorders, which may result in elimination during endurance competitions. Objectives: To evaluate the serum concentration of SAA as a potential indicator for the status of horses prepared for long distance endurance rides (120 and 160 km). Materials and methods: Twenty Arabian horses were tested and 12 were eliminated during the ride and 8 completed the distances. Routine haematological and biochemical tests and measurement of serum concentrations of SAA were carried out before and after the competition. Results were compared using the Mann Whitney U test. Results: Before the competition all haematological and biochemical parameters varied within reference ranges with no differences between the eliminated horses and the ones that successfully finished the competition. After the rides creatine phosphokinase activity and neutrophil: lymphocyte ratio reflecting exercise-induced leukogram changes increased (P<0.05) in both groups. Before the competition, the concentration of SAA remained within reference ranges; however, it was significantly (P<0.05) lower in horses that successfully finished the competition than in eliminated ones (411.7 144 ng/ml vs. 5809.5 2242.7 ng/ml). After the ride SAA levels increased (P<0.05) and were similar in both groups (13 833.8 1354.3 ng/ml and 12 831.2 1317.6 ng/ml). Conclusions: Serum SAA level was the only laboratory parameter that indicated most (66.6%) of the eliminated horses before entering the competition. None of the horses with SAA level higher than 1000 ng/ml completed the distance. Thus, it may be postulated that serum SAA concentration may indicate a poor status of a horse, resulting in elimination during a competition.

Serum amyloid A level as a potential indicator of the status of endurance horses.

http://equievo.pl/wp-content/uploads/2014/12/Gender_differences_in_exercise.pdf

Gender differences in exercise--induced intravascular haemolysis during race training in thoroughbred horses.

Serum amyloid A (SAA) is the major acute phase protein in horses. Its concentration increases in various pathologies but also in response to prolonged, strenuous effort. The purpose of this study was to establish whether routine race and endurance training produces changes in the SAA level in Arabian horses. Additionally, the differences between SAA response in experienced endurance horses and endurance horses that were beginning their career were investigated. There were no changes in SAA concentrations after race training and endurance training in experienced horses. In horses that were beginning their endurance training, exercise produced an increase in SAA level as compared with rest level. In Arabians, the SAA concentration seems to be a good indicator of endurance training but is useless in race training. The routine training of experienced horses, which were prepared for long distance rides, did not promote any changes in the SAA level. In contrast, a significant increase in the SAA concentration was observed in horses that were beginning their endurance training and were only prepared for moderate distance rides and underwent the same effort. Further research is needed to elucidate whether this difference reflects too heavy training or adaptation to an increasing workload. Additionally, the adaptation to long distance rides in Arabians may include a reduced acute phase response.

/pdf/serum-amyloid-a-saa-concentration-after-training-sessions-in-28mgrxv86g.pdf

Serum amyloid A (SAA) concentration after training sessions in Arabian race and endurance horses

Strenuous exercise is recognized as a stress, which may induce functional immunodeficiency and increase individual susceptibility to infection. It has been shown in equine athletes, that alterations in leukocyte functions occur after moderate and submaximal exertion, however, no data deal with the effect of extreme physical exertion. In this study, we evaluated leukocyte functions (neutrophil oxidative burst and lymphocyte proliferation activity in response to mitogens) in horses following the CEI 3* 162 km endurance ride. Exercise-induced stress was manifested as neutrophilic leukocytosis and lymphopaenia resulting in a significant increase in neutrophil:lymphocyte ratio. The alterations in neutrophil function were expressed as a lower percentage of the cells undergoing oxidative burst. The spontaneous lymphocyte proliferation was very high, however, the cells failed to respond to mitogens. Although a decrease in lymphocyte proliferation in response to mitogens has been reported previously, the pattern determined in our study was unique. It may suggest that during the extreme physical exercise immune cells receive an excessive stimulation from yet undetermined factor(s), which renders them unresponsive to extraneous mitogens. The differences between alterations in leukocyte activities induced by extreme exertion may reflect the exercise type and duration as well as the training status of the horses.

A. Schollenberger

Papers

Acute phase protein concentrations after limited distance and long distance endurance rides in horses

Serum amyloid A level as a potential indicator of the status of endurance horses.

Gender differences in exercise--induced intravascular haemolysis during race training in thoroughbred horses.

Serum amyloid A (SAA) concentration after training sessions in Arabian race and endurance horses

The effect of the 162 km endurance ride on equine peripheral blood neutrophil and lymphocyte functions.