A review of the One Health concept : increasing awareness and collaboration between the Maltese medical and veterinary professionals

The One World, One Health concept was initiated in 2004 by the Wildlife Conservation Society with the aim of establishing an interdisciplinary and crosssectoral approach to preventing epidemic or epizootic diseases and to maintain ecosystem integrity. This concept has gained importance nowadays due to the increase in emerging and re-emerging diseases most of which are zoonotic in nature. Collaboration between the Maltese medical and veterinary professions is necessary to diagnose and control these diseases. A number of points are made questioning the current state of collaboration between these professions, with the aim of increasing the trust and communication between the said professions thus ensuring the best possible defence against diseases which can be a threat to both the human and animal population on the Maltese islandspeer-reviewe

A 10 year review of the number of bovine dairy holdings and the dairy bovine population on the Maltese Islands

The process of identification and registration of bovines and bovine holdings on the Maltese Islands has been computerised since 2002, with the introduction of the National Livestock Database of Malta. This is a computerised and centralised system which has made collection, management and analysis of data possible. The aims of this paper were to study in detail ten year trends in the number of bovine dairy holdings together with the bovine population on these holdings and to compare these trends with those reported in other European countries. Six trends related to the number of bovine dairy holdings and their bovine population were analysed in the study. The general trends showed that there was a significant decrease in the number of dairy holdings, in the bovine population and in the number of female bovines greater than 2 years of age during the study period. The average herd size and the average number of females greater than 2 years of age on the dairy holdings showed no statistically significant changes. On the other hand, a significant increase in the ratio of female to male bovines was registered on these holdings.peer-reviewe

A study of the trends in the Maltese bovine husbandry sector following European Union accession

The creation of one centralised National Livestock Database (NLD) for the islands of Malta and Gozo was of crucial importance in the identification and traceability of bovines from 2002 to date. It was also important in covering legal obligations following Malta’s accession to the European Union (EU) in May 2004. This thesis describes how the processes of identification, registration and traceability of bovines have changed following Malta’s accession to the EU. The validation and integration of data originating from the different departmental sections such as the Identification and Registration section, the slaughterhouse and the National Veterinary Laboratory ensures that any discrepancies are highlighted and can be investigated. The various events recorded on the database allow for the cross-checking of compliance and eligibility of bovine producers applying for EU benefits. The main drawbacks and weak points of the system include financial costs for the government department, potentially late notification of births and deaths of new born calves and the insufficient uptake in the use of the latest technology by bovine producers for the notification of events such as births, deaths and movement of bovines. The fact that the NLD is a computerised and centralised system has made collection, management and analysis of data possible. As a result principles of data mining have been used in this thesis to study in detail ten year trends in the number of bovine dairy holdings together with the bovine population on these holdings and to compare these trends with those reported in other European countries. Six trends related to the number of bovine dairy holdings and their bovine population were analysed in the study: the trend in the number of dairy holdings on the Maltese Islands; the trend in the total number of bovines on dairy holdings; the trend in the number of female bovines over two years of age (F>2y); the trend in the average bovine population (average herd size) on dairy holdings; the trend in the average number of female bovines over two years of age; the trend in the number of female and male bovines and their ratios. The general trends showed that there was a significant decrease in the number of dairy holdings, in the bovine population and in the number of female bovines greater than 2 years of age on dairy holdings during the study period. The average herd size and the average number of females greater than 2 years of age on the individual dairy holdings showed no statistically significant changes. On the other hand, a significant increase in the ratio of female to male bovines was registered on these holdings. In the final part of this thesis, data on calf deaths was used to determine the overall mortality rates of live born calves up to 180 days of age in dairy herds on the islands of Malta and Gozo. This is the first time that data using the NLD is being used to determine the calf mortality rates from the whole dairy population of Malta and Gozo. Furthermore, five risk factors namely the island of birth, sex of calf, average herd size, the year and the season of birth were also studied. The data set used in the study consisted of a total of 44,078 calves born between 1 January 2004 and 31 December 2011. From this dataset, 28,848 calves were born in Malta and 15,230 in Gozo. In total 2,821 calves were registered as having died before reaching 180 days of age. The overall calf mortality rate in live born calves up to 180 days of age was found to be 7.08%. In Malta the overall mortality rate was 6.05% and in Gozo 8.80% (P<0.001). The overall mortality rate was 8.50% for male calves and 6.00% for females (P<0.001). Holdings with a lower average herd size had a significantly lower calf mortality rate (P = 0.01) whereas no significant difference was found when the season of birth was taken into consideration. A significant difference (P<0.001) was present when calf mortality was stratified by the year of birth, with the last three years of the study having a lower mortality rate than the first five years

Vrednovanje stope smrtnosti u teladi mliječnih goveda uzgajanih na otocima Malta i Gozo.

The aim of this study was to determine the overall mortality rates of live born calves up to 180 days of age in dairy herds on the islands of Malta and Gozo. Five risk factors, namely: the island of birth, sex of calf, average herd size, the year and season of birth, were also studied. The data set used in the study consisted of a total of 44,078 calves, born between 1 January 2004 and 31 December 2011, from all the dairy herds of both islands. From this dataset, 28,848 calves were born on Malta and 15,230 on Gozo. In total 2,821 calves were registered as having died before reaching 180 days of age. The overall calf mortality rate in live born calves up to 180 days of age was found to be 7.08 %. On Malta the overall mortality rate was 6.05 % and on Gozo 8.80 % (P<0.001). The overall mortality rate was 8.48 % for male calves and 5.99 % for females (P<0.001). Holdings with a lower average herd size had a significantly lower calf mortality rate (P = 0.01), whereas no significant difference was found when the season of birth was taken into consideration. A significant difference (P<0.001) was present when calf mortality was stratified by the year of birth, with the last 3 years of the study having a lower mortality rate than the first 5 years. This study is of relevance since calf mortality rates and the risk factors described are being investigated for the first time on Malta and Gozo.Cilj ovog istraživanja bio je utvrditi ukupne stope smrtnosti do 180. dana u živorođene teladi mliječnih goveda, uzgajanih na otocima Malta i Gozo. Istraženo je i pet čimbenika rizika: otok rođenja, spol teleta, prosječna veličina stada te godina i sezona teljenja. Skup podataka uključivao je ukupno 44 078 teladi, oteljene između 1. siječnja 2004. i 31. prosinca 2011. godine u svim stadima mliječnih goveda s oba otoka. Od navedenog broja 28 848 oteljeno je na Malti, a 15 230 na otoku Gozo. Ukupno 2 821 tele uginulo je prije postizanja dobi od 180 dana, što čini ukupnu stopu mortaliteta od 7,08 %. Na otoku Malta ukupna stopa smrtnosti bila je 6,05 %, a na otoku Gozo 8,80 % (P<0,001). Ukupna stopa smrtnosti za mušku telad bila je 8,48 %, a za žensku telad 5,99 % (P<0,001). Držaoci goveda s nižom prosječnom veličinom stada imali su značajno nižu stopu smrtnosti teladi (P = 0,01), što nije bilo kada se u obzir uzela sezona teljenja. Značajna razlika (P<0,001) utvrđena je kada se smrtnost teladi razvrstala prema godini teljenja, pri čemu je smrtnost u posljednje 3 godine istraživanja manja u odnosu na smrtnost u prvih 5 godina istraživanja. Istraživanje je važno s obzirom na prvi opis stope mortaliteta i čimbenika rizika u teladi s otoka Malta i otoka Gozo

Deletion of Nkx2-5 in trabecular myocardium reveals the developmental origins of pathological heterogeneity associated with ventricular non-compaction cardiomyopathy.

Left ventricular non-compaction (LVNC) is a rare cardiomyopathy associated with a hypertrabeculated phenotype and a large spectrum of symptoms. It is still unclear whether LVNC results from a defect of ventricular trabeculae development and the mechanistic basis that underlies the varying severity of this pathology is unknown. To investigate these issues, we inactivated the cardiac transcription factor Nkx2-5 in trabecular myocardium at different stages of trabecular morphogenesis using an inducible Cx40-creERT2 allele. Conditional deletion of Nkx2-5 at embryonic stages, during trabecular formation, provokes a severe hypertrabeculated phenotype associated with subendocardial fibrosis and Purkinje fiber hypoplasia. A milder phenotype was observed after Nkx2-5 deletion at fetal stages, during trabecular compaction. A longitudinal study of cardiac function in adult Nkx2-5 conditional mutant mice demonstrates that excessive trabeculation is associated with complex ventricular conduction defects, progressively leading to strain defects, and, in 50% of mutant mice, to heart failure. Progressive impaired cardiac function correlates with conduction and strain defects independently of the degree of hypertrabeculation. Transcriptomic analysis of molecular pathways reflects myocardial remodeling with a larger number of differentially expressed genes in the severe versus mild phenotype and identifies Six1 as being upregulated in hypertrabeculated hearts. Our results provide insights into the etiology of LVNC and link its pathogenicity with compromised trabecular development including compaction defects and ventricular conduction system hypoplasia

A study of the trends in the Maltese bovine husbandry sector following European Union accession

The creation of one centralised National Livestock Database (NLD) for the islands of Malta and Gozo was of crucial importance in the identification and traceability of bovines from 2002 to date. It was also important in covering legal obligations following Malta’s accession to the European Union (EU) in May 2004. This thesis describes how the processes of identification, registration and traceability of bovines have changed following Malta’s accession to the EU. The validation and integration of data originating from the different departmental sections such as the Identification and Registration section, the slaughterhouse and the National Veterinary Laboratory ensures that any discrepancies are highlighted and can be investigated. The various events recorded on the database allow for the cross-checking of compliance and eligibility of bovine producers applying for EU benefits. The main drawbacks and weak points of the system include financial costs for the government department, potentially late notification of births and deaths of new born calves and the insufficient uptake in the use of the latest technology by bovine producers for the notification of events such as births, deaths and movement of bovines. The fact that the NLD is a computerised and centralised system has made collection, management and analysis of data possible. As a result principles of data mining have been used in this thesis to study in detail ten year trends in the number of bovine dairy holdings together with the bovine population on these holdings and to compare these trends with those reported in other European countries. Six trends related to the number of bovine dairy holdings and their bovine population were analysed in the study: the trend in the number of dairy holdings on the Maltese Islands; the trend in the total number of bovines on dairy holdings; the trend in the number of female bovines over two years of age (F>2y); the trend in the average bovine population (average herd size) on dairy holdings; the trend in the average number of female bovines over two years of age; the trend in the number of female and male bovines and their ratios. The general trends showed that there was a significant decrease in the number of dairy holdings, in the bovine population and in the number of female bovines greater than 2 years of age on dairy holdings during the study period. The average herd size and the average number of females greater than 2 years of age on the individual dairy holdings showed no statistically significant changes. On the other hand, a significant increase in the ratio of female to male bovines was registered on these holdings. In the final part of this thesis, data on calf deaths was used to determine the overall mortality rates of live born calves up to 180 days of age in dairy herds on the islands of Malta and Gozo. This is the first time that data using the NLD is being used to determine the calf mortality rates from the whole dairy population of Malta and Gozo. Furthermore, five risk factors namely the island of birth, sex of calf, average herd size, the year and the season of birth were also studied. The data set used in the study consisted of a total of 44,078 calves born between 1 January 2004 and 31 December 2011. From this dataset, 28,848 calves were born in Malta and 15,230 in Gozo. In total 2,821 calves were registered as having died before reaching 180 days of age. The overall calf mortality rate in live born calves up to 180 days of age was found to be 7.08%. In Malta the overall mortality rate was 6.05% and in Gozo 8.80% (P<0.001). The overall mortality rate was 8.50% for male calves and 6.00% for females (P<0.001). Holdings with a lower average herd size had a significantly lower calf mortality rate (P = 0.01) whereas no significant difference was found when the season of birth was taken into consideration. A significant difference (P<0.001) was present when calf mortality was stratified by the year of birth, with the last three years of the study having a lower mortality rate than the first five years.La creazione di un database nazionale centralizzato per bovini (NLD: National Livestock Database) per le isole di Malta e Gozo è risultato di importanza cruciale per l’identificazione e la rintracciabilità dei bovini dal 2002 ad oggi. Divenne inoltre un obbligo legislativo a seguito dell'adesione di Malta all'Unione Europea (UE) nel maggio 2004. La presente Tesi descrive come i processi di identificazione, registrazione e tracciabilità dei bovini siano cambiati dopo l’adesione di Malta all'UE. La validazione e l'integrazione dei dati provenienti da diverse sezioni dipartimentali, come la sezione di identificazione e registrazione dei bovini, il macello ed il laboratorio veterinario nazionale, assicurano che le eventuali discrepanze siano evidenziate e possano essere investigate. I vari eventi registrati nel database consentono inoltre il controllo incrociato di conformità ed ammissibilità degli allevatori ai benefici previsti dall’EU. I principali svantaggi ed i punti deboli del sistema sono rappresentati dagli alti costi finanziari per il dipartimento del governo, dalle notifiche di nascite e morte talvolta tardive e dalle difficoltà di implementazione tecnologica da parte degli allevatori, necessaria per la notifica degli eventi come nascite, decessi e movimentazione dei bovini stessi. Tuttavia, la gestione computerizzata e centralizzata della NLD ha permesso un’efficiente raccolta, elaborazione ed analisi dei dati. Pertanto, con la presente Tesi è stato possibile studiare l’evoluzione nel numero di aziende di bovine da latte in tali popolazioni negli ultimi 10 anni, la numerosità di capi nelle aziende stesse e confrontare questi dati con quelli segnalati in altri paesi Europei. Nello studio sono stati analizzati 6 fattori legati alla numerosità degli allevamenti ed al numero di capi per allevamento: il trend del numero di aziende di bovine da latte sulle isole maltesi; il trend del numero totale dei bovini da latte nelle aziende; il trend del numero di bovine femmine superiori ai due anni di età (F > 2y); il trend delle dimensioni medie delle mandrie; l'andamento del numero medio di bovine femmine superiori ai 2 anni di età su ogni allevamento; l'andamento del numero di bovine femmine e maschi e il rapporto femmine-maschi. I risultati generali indicano che durante il periodo di studio si è verificata una diminuzione significativa del numero di aziende di bovine da latte come pure della popolazione bovina complessiva, ed in particolare nel numero di bovine superiori ai 2 anni di età. Le dimensioni delle mandrie ed il numero medio di femmine superiori ai 2 anni di età su ogni allevamento non hanno mostrato variazioni statisticamente significative. D'altra parte, un aumento significativo del rapporto femmine-maschi è stato registrato in queste aziende. Nella parte finale della presente Tesi sono stati presentati i dati sui decessi, necessari per evidenziare il tasso di mortalità fino ai 180 giorni di età dei vitelli nati vivi in allevamenti presenti nelle isole di Malta e Gozo; tali elaborazioni sulla mortalità risultano ancor più rilevanti dal momento che questi risultati rappresentano i primi dati elaborati e presentati da quando è presente il NLD in tali popolazioni di Malta e Gozo. Sono stati inoltre analizzati 5 fattori di rischio: isola di nascita, sesso del vitello, dimensione media della mandria, anno di nascita e stagione di nascita. Il set di dati utilizzato nello studio era composto da un totale di 44.078 vitelli nati tra il 1 gennaio 2004 ed il 31 dicembre 2011. Da questo dataset, 28.848 vitelli sono nati a Malta e 15.230 a Gozo. In totale, 2.821 vitelli sono stati registrati come morti prima di raggiugere i 180 giorni di età, con un tasso di mortalità complessivo in vitelli nati vivi fino a 180 giorni di età pari al 7.08%, con una differenza statisticamente significativa (P< 0.001) tra Malta e Gozo, 6.05% ed 8.80%, rispettivamente. Il tasso di mortalità generale è risultato del 8,50% per vitelli maschi e 6,00% per le femmine. Aziende con una dimensione della mandria relativamente bassa hanno presentato un tasso di mortalità dei vitelli significativamente inferiore (P = 0.01) a quelle piu numerose. Nessuna differenza significativa è stata riscontrata in merito alla stagione di nascita, mentre delle differenze sono state evidenziate in merito alla mortalità a seconda dell’anno di nascita, dove gli ultimi 3 anni dello studio hanno mostrato un tasso di mortalità piu basso rispetto ai precedenti 5 anni

Morphology of adult hypertrabeculation induced by conditional deletion of <i>Nkx2-5</i> in cardiomyocytes during trabecular development.

<p>(A) Short-axis cine images recorded by CMR at end-diastole show anatomical structures of LV of 3 months-old control (CTL), <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} (ΔTrbE10) and <i>Nkx2-5</i>^{<i>ΔTrbE14</i>} (ΔTrbE14) mutant mice. Stars indicate the papillary muscles, and arrowheads indicate excessive trabeculations. RV: right ventricle; IVS: interventricular septum; LV: left ventricle. Scale bar = 1mm. (B) Eosin staining on transversal sections of the mid-ventricle from control, <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} and <i>Nkx2-5</i>^{<i>ΔTrbE14</i>} adult hearts. The dotted lines delimit the boundary between trabecular and compact zones in LV. (C) Immunofluorescence with endoglin, SMA and VEGFR2 antibodies to delineate endocardium (Eng^high/VEGFR2^-) and vascular endothelial cells (Eng^low/VEGFR2⁺) on transversal sections of the mid-ventricle from control, <i>Nkx2-5</i>^{<i>ΔTrbE10</i>}, and <i>Nkx2-5</i>^{<i>ΔTrbE14</i>} adult hearts. Scale bar = 500μm. On the right panel, high magnifications of the left ventricular lumen show the numerous endocardial islets detected in <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} and <i>Nkx2-5</i>^{<i>ΔTrbE14</i>} mutants (arrows). Scale bar = 100μm. (D) Perfusion of WGA-Cy3 lectin in the ventricle of control and <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} hearts. (E) Immunofluorescence with endoglin, VEGFR2 and perfused WGA to detect the endocardium. Scale bar = 1mm. Below, high magnification of Eng+/VEGFR2- endocardial islets stained with perfused WGA-Cy3 (arrows). Scale bar = 100μm. (F-G) Quantification of the degree of excessive trabeculations by measuring the total length of the endocardium layer. These measures were performed for 3 sections at the level of the apex and at mid-ventricle from control (N = 3), <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} (** p < 0,005, N = 3) and <i>Nkx2-5</i>^{<i>ΔTrbE14</i>} (*p < 0,05, N = 3) adult hearts (F), and counting the number of endocardial islets per section (G) (**p < 0,002, N = 3 for <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} <i>vs</i> control and ^$ p < 0,02, N = 3 <i>vs Nkx2-5</i>^{<i>ΔTrbE14</i>}).</p

Hypertrabeculated <i>Nkx2-5</i> mutant hearts exhibit QRS defects, BB blocks and high susceptibility to fibrillation.

<p>(A) Representative tracings from surface ECG measured in lead II in anaesthetized mice at 3-, 6- and 9-month old. In control mice, QRS complexes are normal regardless of the age at which they were recorded. Tracings from <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} and <i>Nkx2-5</i>^{<i>ΔTrbE14</i>} mice demonstrated bundle branch block-like appearance with widened QRS complex and a characteristic pattern with Notched R, R' wave and fragmented QRS. (B) Dobutamine caused a marked increase of heart rate in control mice and only a small effect in <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} and <i>Nkx2-5</i>^{<i>ΔTrbE14</i>} mice. (C) Severe susceptibility to ventricular fibrillation was found in <i>Nkx2-5</i>^{<i>ΔTrbE10</i>} and <i>Nkx2-5</i>^{<i>ΔTrbE14</i>} mutants but not in control mice. Cardiac frequency and quantification of arrhythmias and fibrillation before and after Dobutamine injection are summarized in the table. (D) Plots of QRS duration in lead II from 9-month old mice against Ejection Fraction (EF) recorded during echocardiography (N = 27) and MRI (N = 11) or against LV mass from MRI (N = 11). Red and green dots represent mice with fluctuating EF overtime. Linear relationships were observed and R² and p-values were indicated for each graph.</p