Investigating Visual Monitoring of the Scrotum as a Supplementary Tool for Boar Semen Quality Evaluation

Farm animals behavior research uses video cameras, mainly for visual observation and recording. The purpose of this feasibility study was to enrich the predictable methods of boar semen production capacity by correlating sperm variables with the scrotal contractions (SC) frequency and intensity. A video camera was used to record the reaction of the scrotum during ejaculation. The respective collected ejaculates were evaluated and semen parameters, such as viability, morphology, membranes functional integrity and kinematics, were determined. The camera recorded the scrotal contractions/relaxations and the video was handled by the Image Processing Toolbox of Matlab (Mathworks Inc., Natick, MA, USA). The SC intensity was verified as a percentage change in the scrotum size among the video frames of maximum contraction and relaxation. The archived data from the frames were analyzed statistically, using a linear mixed effects model that involved sperm assessed parameters. Correlations of the SC intensity with the average path velocity, VAP (R2 = 0.591, p = 0.043) and with the percentage of the cytoplasmic droplets (R2 = 0.509, p = 0.036) were noticed. Previous studies reported the positive correlation of VAP with the number of live-born piglets. In conclusion, video monitoring of the boar scrotal function during ejaculation is useful, but more research is needed to establish its appropriateness as a supplementary method for the prognosis of boar ability to produce high-quality semen

Investigation of changes in the fertilizing ability of boar sperm using biomedical techniques

Τhe aim of the present study was a) to record boar behavior immediately before and during ejaculation using biomedical sensors, b) to evaluate sperm fertilizing capacity performing in vitro tests, and c) to correlate the recorded biomedical data with the examined sperm quality and functional characteristics. Five boars were used in the study and ninety-four ejaculates were collected. All the collected semen samples were analyzed for motility and kinetics by computer-assisted semen analysis, viability and morphology, sperm membrane biochemical activity (HOST), and sperm chromatin integrity. The following sensors were involved in the experiments:- an inertial measurement unit (IMU), comprising an accelerometer (overall dynamic body acceleration; ODBA), a gyroscope and a magnetometer, was placed on boar body to record its movement features,- an infrared (IR) camera and an IR thermometer for recording the temperature of the boar scrotal and body, as well as of the dummy-a moisture meter (based on IR technology) for depicting the boar face salivation, -a video camera for recording the scrotum function, which includes the scrotal contractions and relaxations during ejaculation, and- a galvanic skin response sensor (GSR) for assessing the skin electrical conductivity of the boars. Significant and strong negative correlations were observed between boar, dummy and scrotal temperature with the progressive motility, rapid and slow movement spermatozoa, VCL, VSL and ALH. The volume of the ejaculate was negatively correlated with the dummy and scrotal temperature. Dummy’s temperature was negatively correlated with BCF, viability and total time of ejaculation, while it was positively correlated with the slow movement spermatozoa and abnormal morphology. Body temperature was negatively correlated with BCF. The total time of ejaculation was positively correlated with median ODBA and acceleration. The mean total acceleration was positively correlated with VAP, while salivation of the boar was positively correlated with median ODBA. Based on the correlation between quality and quantity semen characteristics, morphologically normal spermatozoa and viability were positively correlated with progressive motility, rapid movement spermatozoa, VCL, VSL, VAP, ALH, and BCF. Viability was negatively correlated with slow movement spermatozoa and spermatozoa with morphologically abnormal head, neck or retained cytoplasmic droplet. The morphological abnormalities of head, neck, tail and the retained cytoplasmic droplet were negatively correlated with progressive motility, rapid-movement spermatozoa, VCL and VSL. The HOST positive spermatozoa were positively correlated with rapid-movement spermatozoa, VCL and VSL, while HOST negative spermatozoa were negatively correlated with BCF. The total time of ejaculation was positively correlated with the ejaculation volume. The scrotal intensity was positively correlated with VAP and the percentage of spermatozoa with retained cytoplasmic droplets. Finally, no homogeneous results of GSR were found. In conclusion, boar scrotal, body and dummy temperature, median ODBA, salivation, total time of ejaculation and scrotal intensity can be reliably measured using biomedical techniques, be correlated with quality characteristics of semen and contribute to the creation of a predictive model for the selection of boars with the possibility of producing high quality semen.Η παρούσα μελέτη διερευνά τη σχέση της ποιότητας του σπέρματος (κινητικές παράμετροι, ζωτικότητα, μορφολογία, HOSTtest, κατακερματισμός του DNA) με τη συμπεριφορά του κάπρου κατά την εκσπερμάτιση με χρήση βιοϊατρικών τεχνικών. Επιπλέον, συσχετίζει τα συλλεγόμενα βιοϊατρικά δεδομένα με τα ποιοτικά χαρακτηριστικά του σπέρματος, υποστηρίζοντας τη χρησιμότητά τους ως πρόσθετο εργαλείο για την αξιολόγηση της ικανότητας του κάπρου να παράγει σπέρμα υψηλής ποιότητας. Για την πραγματοποίηση των πειραματισμών, εξετάσθηκαν 94 εκσπερματίσματα και χρησιμοποιήθηκαν 5 σπερματοδότες κάπροι, στους οποίους τοποθετήθηκαν αισθητήρες. Τα χαρακτηριστικά της κίνησής τους καταγράφονταν με αισθητήρα που περιελάμβανε επιταχυνσιόμετρο, γυροσκόπιο και μαγνητόμετρο. Οι θερμοκρασίες του ομοιώματος επίβασης, του οσχέου και του σώματος των κάπρων μετρήθηκαν με υπέρυθρη κάμερα, ενώ η σιελόρροια στις παρειές των κάπρων καταγραφόταν με ειδική θερμική κάμερα. Η ηλεκτρική αγωγιμότητα του δέρματος των κάπρων καταγραφόταν από αισθητήρα γαλβανικού συστήματος απόκρισης δέρματος. Παρατηρήθηκαν ισχυρά αρνητικές συσχετίσεις μεταξύ της θερμοκρασίας του ομοιώματος επίβασης, του οσχέου και του σώματος των κάπρων με την προοδευτική κίνηση, τα βραδείας και ταχείας κίνησης σπερματοζωάρια και τις εκτιμώμενες με αυτόματο αναλυτή (CASA) κινητικές παραμέτρους VCL, VSL και ALH. Ο όγκος της εκσπερμάτισης συσχετίστηκε αρνητικά με τη θερμοκρασία του ομοιώματος και του οσχέου. Η θερμοκρασία του ομοιώματος συσχετίστηκε αρνητικά με την BCF, τη ζωτικότητα και τον συνολικό χρόνο εκσπερμάτισης, ενώ συσχετίστηκε θετικά με τα σπερματοζωάρια βραδείας κίνησης και τη μη φυσιολογική μορφολογία. Η θερμοκρασία του σώματος συσχετίστηκε αρνητικά με την BCF. Όσον αφορά την κινητικότητα των κάπρων, προέκυψε ότι η συνολική διάρκεια της εκσπερμάτισης συσχετίζεται θετικά με τη διάμεση ODBAκαι τη μέση συνολική επιτάχυνση. Επιπλέον, η μέση συνολική επιτάχυνση συσχετίζεται θετικά με την VAP, ενώ η σιελόρροια συσχετίζεται θετικά με τη διάμεση ODBA.Κατά τη συσχέτιση των ποιοτικών και ποσοτικών χαρακτηριστικών του σπέρματος, η φυσιολογική μορφολογία και η ζωτικότητα των σπερματοζωαρίων συσχετίστηκαν ισχυρά θετικά μεταξύ τους και με την προοδευτική κινητικότητα, τα σπερματοζωάρια ταχείας κίνησης και τιςVCL, VSL, VAP, ALH και BCF. Ακόμη, η ζωτικότητα συσχετίστηκε ισχυρά αρνητικά με τα σπερματοζωάρια βραδείας κίνησης, τις μορφολογικές ανωμαλίες της κεφαλής, του αυχένα και τα σπερματοζωάρια με κυτταροπλασματικό σταγονίδιο. Οι μορφολογικές ανωμαλίες της κεφαλής, του αυχένα, της ουράς και του παραμένοντος κυτταροπλασματικού σταγονιδίου συσχετίστηκαν αρνητικά με την προοδευτική κινητικότητα, τα ταχέως κινούμενα σπερματοζωάρια και τις VCL και VSL. Το ποσοστό των HOST θετικών σπερματοζωαρίων συσχετίστηκε ισχυρά θετικά με τα ταχέως κινούμενα σπερματοζωάρια και τιςVCL και VSL, ενώ το ποσοστό των HOST αρνητικών συσχετίστηκε αρνητικά με τη BCF. Ο συνολικός χρόνος εκσπερμάτισης συσχετίσθηκε ισχυρά θετικά με τον όγκο του εκσπερματίσματος. Η ένταση των συσπάσεων των όρχεων κατά την εκσπερμάτιση συσχετίστηκε θετικά με την VAP και το ποσοστό των σπερματοζωαρίων με κυτταροπλασματικό σταγονίδιο.Τα αποτελέσματα της ηλεκτρικής αγωγιμότητας του δέρματος δεν ήταν ομοιογενή. Συμπερασματικά, η θερμοκρασία του ομοιώματος, του οσχέου και του σώματος του κάπρου, η διάμεση ODBA, η σιελόρροια, η χρονική διάρκεια της εκσπερμάτισης και η ένταση των συσπάσεων των όρχεων μπορούν να μετρηθούν αξιόπιστα με την χρήση βιοϊατρικών τεχνικών και, έπειτα από συσχέτισή τους με τα ποιοτικά χαρακτηριστικά του σπέρματος, να συμβάλλουν στην δημιουργία προγνωστικού μοντέλου επιλογής κάπρων με δυνατότητα παραγωγής σπέρματος υψηλής ποιότητας

Investigating Visual Monitoring of the Scrotum as a Supplementary Tool for Boar Semen Quality Evaluation

Farm animals behavior research uses video cameras, mainly for visual observation and recording. The purpose of this feasibility study was to enrich the predictable methods of boar semen production capacity by correlating sperm variables with the scrotal contractions (SC) frequency and intensity. A video camera was used to record the reaction of the scrotum during ejaculation. The respective collected ejaculates were evaluated and semen parameters, such as viability, morphology, membranes functional integrity and kinematics, were determined. The camera recorded the scrotal contractions/relaxations and the video was handled by the Image Processing Toolbox of Matlab (Mathworks Inc., Natick, MA, USA). The SC intensity was verified as a percentage change in the scrotum size among the video frames of maximum contraction and relaxation. The archived data from the frames were analyzed statistically, using a linear mixed effects model that involved sperm assessed parameters. Correlations of the SC intensity with the average path velocity, VAP (R2 = 0.591, p = 0.043) and with the percentage of the cytoplasmic droplets (R2 = 0.509, p = 0.036) were noticed. Previous studies reported the positive correlation of VAP with the number of live-born piglets. In conclusion, video monitoring of the boar scrotal function during ejaculation is useful, but more research is needed to establish its appropriateness as a supplementary method for the prognosis of boar ability to produce high-quality semen

The Use of Animal’s Body, Scrotal Temperature and Motion Monitoring in Evaluating Boar Semen Production Capacity

Biomedical measurements by specialized technological equipment have been used in farm animals to collect information about nutrition, behavior and welfare. This study investigates the relation of semen quality (CASA analysis, viability, morphology, membrane biochemical activity and DNA fragmentation) with boar behavior during ejaculation. Sensors were placed on the boar’s body. Movement features were collected using an inertial measurement unit (IMU), comprising an accelerometer, a gyroscope and a magnetometer. Boar, scrotal and dummy temperatures were measured by an infrared (IR) camera and an IR thermometer, while the face salivation of the boar was recorded by a moisture meter (also based on IR technology). All signals and images were logged on a mobile device (smartphone or tablet) using a Bluetooth connection and then transferred wirelessly to the cloud. The data files were then processed using scripts in MATLAB 2021a (MathWorks, Natick, Massachusetts) to derive the necessary indices. Ninety-four ejaculates from five boars were analyzed in this study. The statistical analysis was performed in the Statistics and Machine Learning Toolbox of MATLAB 2021a using a linear mixed effects model. Significant and strong negative correlations (R2 > 0.5, p ≤ 0.05) were observed between boar, dummy and scrotal temperature with the progressive, rapid and slow movement of spermatozoa, VCL (curvilinear velocity), VSL (straight line velocity) and ALH (amplitude of lateral head displacement) kinematics. The volume of the ejaculate was correlated with the scrotal and dummy temperature. Dummy’s temperature was negatively correlated with BCF (beat/cross-frequency), viability and total time of ejaculation, while it was positively correlated with abnormal morphology. Body temperature was negatively correlated with BCF. Positive correlations were noticed between VAP (average path velocity) and total time of ejaculation with body acceleration features, as well as between the overall dynamic body acceleration (ODBA) and total time of ejaculation. In conclusion, the use of biomedical sensors can support the evaluation of boar sperm production capacity, providing valuable information about semen quality