Αναπαραγωγικό και Αναπνευστικό Σύνδρομο του Χοίρου (ΑΑΣΧ) και δευτερογενείς επιπλοκές: Νεότερα δεδομένα, οικονομικές επιπτώσεις και παρούσα κατάσταση στην Ελλάδα
Δημοσιευμένα:
Νοε 24, 2017
Λέξεις-κλειδιά:
ΑΑΣΧ δευτερογενείς επιπλοκές οικονομικές επιπτώσεις Ελλάδα
Περίληψη
Η κλινική εικόνα του Αναπαραγωγικού και Αναπνευστικού Συνδρόμου του Χοίρου (ΑΑΣΧ) ποικίλλει και χαρακτηρίζεται από υποκλινικά έως σοβαρά αναπαραγωγικά και αναπνευστικά συμπτώματα. Η σοβαρότητα των συμπτωμάτων εξαρτάται από διάφορους παράγοντες, μεταξύ των οποίων από τη λοιμογόνο ικανότητα του υπευθύνου στελέχους του ίου, τον πιθανό ανασυνδυασμό των διαφόρων στελεχών που είναι υπεύθυνα για την εκδήλωση του ΑΑΣΧ μέσα στην ίδια εκτροφή, της ταυτόχρονης εκδήλωσης άλλων ιογενών και βακτηριακών νοσημάτων, καθώς καιτου προγράμματος κτηνιατρικής διαχείρισης που εφαρμόζεται στην εκτροφή. Η αλληλεπίδραση μεταξύ ιών και βακτηρίων έχει καταδειχθεί από πολλούς ερευνητές και κατά το συνηθέστερο πρότυπο αλληλεπίδρασης τα δευτερογενή παθογόνα βακτήρια επιπλέκουν τις αλλοιώσεις που προκλήθηκαν από τους ιούς. Η μόλυνση από τον ιό του ΑΑΣΧ προδιαθέτει την προσβολή των απογαλακτισμένων χοιριδίων από το Streptococcus suis και αυξάνει τηνευαισθησία των χοίρων στη μόλυνση από Salmonella choleraesuis, Bordetella bronchiseptica, Mycoplasma hyopneumoniae και Mycoplasma hyorhinis. Επίσης, ο ιός του ΑΑΣΧ εμπλέκεται στην αιτιοπαθογένεια του Αναπνευστικού Συνδρόμου των Αναπτυσσόμενων/Παχυνόμενων Χοίρων (ΑΣΑΠΧ), του Πολυσυστηματικου Συνδρόμου Απίσχνανσης των Απογαλακτισμένων Χοιριδίων(ΠΣΑΑΧ) και του Συνδρόμου Δερματίτιδας και Νεφροπάθειας του Χοίρου (ΣΔΝΧ) και προδιαθέτει την εκδήλωση τους. Στους παχυνόμενους χοίρους, η συνύπαρξη του ΑΑΣΧ με την αναπνευστική μορφή της νόσου του Aujeszky και με τη γρίπη του χοίρου αποτελείαιτία σοβαρών απωλειών στις εκτροφές, εξαιτίας των αναπνευστικών προβλημάτων που προκαλούνται. Στα περιστατικά μικιών λοιμώξεων του ΑΑΣΧ με άλλους παθογόνους βακιηριακουςή/και ιογενείς παράγοντες, το κόστος παραγωγής αυξάνεται κατακόρυφα όχι μόνο από τις απώλειες που προκαλούνται, αλλά κυρίως από τη χρήση υποστηρικτικών θεραπειών και τη λήψη ειδικών προληπτικών μέτρων. Στην Ελλάδα, μέχρι σήμερα, το σύνδρομο συνεχίζει να εκδηλώνεται με την ενζωοτική μορφή του (ανεξάρτητα από την εποχή του έτους), που χαρακτηρίζεται από περιορισμένης διάρκειας εξάρσεις και υφέσεις. Ο ιός του ΑΑΣΧ συμμετέχει ως πρωτογενής παθογόνος παράγοντας στα αίτια θανάτων των αναπτυσσόμενων/παχυνόμενων χοίρων των ελληνικών εκτροφών. Επιπλέον,τα τελευταία χρόνια, η εμφάνιση των νέων συνδρόμων του ΑΣΑΠΧ, του ΠΣΑΑΧ και του ΣΔΝΧ, σε συνδυασμό με την παρουσίατου ΑΑΣΧ, επιβάρυναν ακόμη περισσότερο την οικονομία των εκτροφών της χώρας μας και το κόστος παραγωγής του εγχώρια παραγόμενου χοίρινου κρέατος. Από μη δημοσιευμένα στοιχεία των συγγραφέων της παρούσας εργασίας, τον τελευταίο χρόνο διαπιστώνεται ότι το ΑΑΣΧ και ειδικά η αναπνευστική του μορφή συνεχίζει να προκαλεί σημαντικές απώλειες στην ελληνική χοιροτροφία.Το φαινόμενο παρατηρήθηκε κυρίως σε εκτροφές που εισάγουν νεαρά ζώα αναπαραγωγής ή ακόμη και χοιρίδια προς πάχυνση και δεν λαμβάνουν τα κατάλληλα μέτρα υγεινομικής προετοιμασίας πριν την είσοδο τους στην εκτροφή, όπως απομόνωση σε ξεχωριστό κτίριο (καραντίνα), προσδιορισμό αντισωμάτων για το νόσημα κ.ά. Το εντυπωσιακό είναι ότι σε σημαντικό αριθμό εκτροφών η εμφάνιση εξάρσεων του συνδρόμου παρατηρήθηκε στην ηλικία των παχυνόμενων χοίρων και εκδηλώθηκε με έντονα αναπνευστικά συμπτώματα και συνοδεύτηκε από σημαντικές οικονομικές απώλειες. Οι εξάρσεις αυτές οφείλονταν πιθανότατα στην είσοδο «νέων» διαφορετικών στελεχών του ίου στις εκτροφές με την αγορά νεαρών ζώων αναπαραγωγής ή/και χοιριδίων προς πάχυνση. Προφανώς, τα στελέχη αυτά ήταν περισσότερο λοιμογόνα από τα στελέχη που προϋπήρχαν στις εκτροφές ή ανασυνδυάστηκαν με τα προϋπάρχοντα στελέχη, προκύπτοντας στελέχη με μεγαλύτερη λοιμογόνο ικανότητα. Στις εκτροφές που εκδηλώθηκαν έντονα αναπνευστικά συμπτώματα στους αναπτυσσόμενους/παχυνόμενους χοίρους και απουσίαζαν ή εκδηλώθηκε σε μικρό βαθμό η αναπαραγωγική μορφή του ΑΑΣΧ, πιθανώς είτε ο εμβολιασμός που εφαρμοζόταν στις συες δεν προστάτευε τους αναπτυσσόμενους/παχυνόμενους χοίρους, είτε τα «νέα» στελέχη του ίου που μόλυναν τις εκτροφές ήταν περισσότερο λοιμογόνα ως προς τον τροπισμό τους στο αναπνευστικό παρά στο γεννητικό σύστημα, είτε στη συνύπαρξη όλων των προηγουμένων περιπτώσεων. Σήμερα, το ΑΑΣΧ εξακολουθεί να αποτελεί μια σημαντική «απειλή» για την ελληνική χοιροτροφία και γι' αυτό επιβάλλεται να λαμβάνονται αυστηρά όλα τα απαραίτητα προληπτικά μέτρα κτηνιατρικής βιοασφάλειας και κυρίως: οι εμβολιασμοί, ο περιορισμός της εισαγωγής νεαρών ζώων αναπαραγωγής και να προτιμάται η παραγωγή τους μέσα στην ίδια την εκτροφή από αγέλη πυρήνα, η απομόνωση και ο ορολογικός έλεγχος των νεοεισερχόμενων ζώων (νεαρά ζώα αναπαραγωγής και χοιρίδια προς πάχυνση) πριν από την είσοδοτους σε μια εκτροφή, καθώς και η αγορά τους από γνωστές αρνητικές στον ιό του ΑΑΣΧ εκτροφές. Η εισαγωγή χοιριδίων προς πάχυνση πρέπει να αποφεύγεται, επειδή επιδεινώνει την παρουσία του ΑΑΣΧ στις ελληνικές εκτροφές και περιπλέκει τον έλεγχο του.
Λεπτομέρειες άρθρου
- Πώς να δημιουργήσετε Αναφορές
-
PAPATSIROS (Β.Γ. ΠΑΠΑΤΣΙΡΟΣ) V. G., ALEXOPOULOS (Κ. ΑΛΕΞΟΠΟΥΛΟΣ) C., & KYRIAKIS (Σ.Κ. ΚΥΡΙΑΚΗΣ) S. C. (2017). Αναπαραγωγικό και Αναπνευστικό Σύνδρομο του Χοίρου (ΑΑΣΧ) και δευτερογενείς επιπλοκές: Νεότερα δεδομένα, οικονομικές επιπτώσεις και παρούσα κατάσταση στην Ελλάδα. Περιοδικό της Ελληνικής Κτηνιατρικής Εταιρείας, 58(2), 157–171. https://doi.org/10.12681/jhvms.14982
- Τεύχος
- Τόμ. 58 Αρ. 2 (2007)
- Ενότητα
- Review Articles
Οι συγγραφείς των άρθρων που δημοσιεύονται στο περιοδικό διατηρούν τα δικαιώματα πνευματικής ιδιοκτησίας επί των άρθρων τους, δίνοντας στο περιοδικό το δικαίωμα της πρώτης δημοσίευσης.
Άρθρα που δημοσιεύονται στο περιοδικό διατίθενται με άδεια Creative Commons 4.0 Non Commercial και σύμφωνα με την άδεια μπορούν να χρησιμοποιούνται ελεύθερα, με αναφορά στο/στη συγγραφέα και στην πρώτη δημοσίευση για μη κερδοσκοπικούς σκοπούς.
Οι συγγραφείς μπορούν να καταθέσουν το άρθρο σε ιδρυματικό ή άλλο αποθετήριο ή/και να το δημοσιεύσουν σε άλλη έκδοση, με υποχρεωτική την αναφορά πρώτης δημοσίευσης στο J Hellenic Vet Med Soc
Οι συγγραφείς ενθαρρύνονται να καταθέσουν σε αποθετήριο ή να δημοσιεύσουν την εργασία τους στο διαδίκτυο πριν ή κατά τη διαδικασία υποβολής και αξιολόγησής της.
Λήψεις
Τα δεδομένα λήψης δεν είναι ακόμη διαθέσιμα.
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