Background: Canine dilated cardiomyopathy (DCM) is one of the commonly diagnosed acquired myocardial disease in dogs characterized by hypokinesis, eccentric myocardial hypertrophy. Activation of neurohumoral system (i.e., sympathetic and RAAS) is crucial in the pathogenesis of DCM with deteriorative effect on the failing heart. In current protocol, ACE inhibitors are being employed to counter RAAS through blocking of ACE pathway, however aldosterone breakthrough due to alternate tissue pathway render the treatment less effective. The natriuretic peptides (viz., ANP, BNP) produced in response to cardiac wall stress have beneficial natriuretic, diuretic and suppressed cardiac sympathetic effects, however, will be cleaved by the enzyme neprilysin limiting their activity. With this background, this study was aimed to study the effect of Sacubitril-Valsartan, an ARNi drug in management of canine heart failure due to DCM, evaluating its effects on clinical, echocardiographic parameters as well as on RAAS and natriuretic peptides. 
 
Methods: Dogs with confirmed DCM on echocardiography were randomly divided into two treatment groups, one with conventional protocol having ACEI (Group II) and another group with ARNi replacing ACEI in the protocol (Group III). Clinical signs, ECG, echocardiographic evaluation was done at monthly interval till 90th&nbsp;day of therapy. Radiographic evaluation as well as effect on RAAS by assessing plasma natriuretic peptides and urine aldosterone-creatinine ratio was done on 0th&nbsp;day and 90th&nbsp;days of therapy. Data was analysed using ANOVA and independent &lsquo;t&rsquo; test followed by LSD using IBM SPSS version 2.0. 
 
Result: In the study, group III dogs showed early resolution of clinical signs compared to group II. Group III showed a significant decrease in left atrial diameter and LA/Ao ratio earlier by 30th&nbsp;day of therapy, while in Group II, the same was noticed on the 60th day. Cardiac internal diameters were found to be significantly decreased in group III while group II showed a non-significant decrease. Systolic function was found to be significantly increased by 30th&nbsp;day in group III while group III has a non significant increase in ejection fraction. Significant decline of Uald:cre ratio was noticed in group III indicating its effective inhibition of RAAS. In the study dogs treated with sacubitril-valsartan was found to have faster resolution of clinical signs, greater reduction in cardiac dimensions and improvement in systolic function compared to ACEI treated dogs. 
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Therapeutic Evaluation of Sacubitril-valsartan (Arni) in Canine Dilated Cardiomyopathy

<div>Background: The variety of indigenous duck germplasm contribute maximum to the poultry industry in India, besides chicken population. In southern part of India, the available duck genetic resource, particularly Arni ducks (comprises of Sanyasi and Keeri ducks) of Tamil Nadu, has its own characteristics with innate potentiality of higher productivity without any input system of management. Genetic characterization and diversity of indigenous duck genetic resources has not been properly studied. In the present study, the genetic diversity of Arni ducks with other indigenous and exotic duck germplasm were analysed with microsatellite markers.&nbsp; 
 
Methods: Genomic DNA was isolated from the blood samples of six duck populations. Molecular characterization was carried out with duck specific FAO recommended microsatellite markers. The genotyping of ducks was done based on the size of 4324 PCR amplicons of 23 microsatellite loci, which were subjected to capillary electrophoresis using automatic sequencer. 
 
Result: A total of 222 alleles in six duck populations across 23 microsatellite loci with a mean of 9.65&plusmn;0.95 alleles were found. Kuttanad duck variety had the highest number of alleles (139) followed by Sanyasi (136), Keeri (129), Muscovy (118), Assam (91) and White Pekin (78) ducks. The mean observed number of alleles was 6.04&plusmn;0.59, 5.91&plusmn;0.76, 5.61&plusmn;3.17, 5.13&plusmn;0.44, 3.96&plusmn;0.76 and 3.39&plusmn;0.40 in Kuttanad, Sanyasi, Keeri, Muscovy, Assam and White Pekin ducks respectively. The overall mean polymorphism information content (PIC) values among the six duck populations was 0.6269. &nbsp;In most of the duck populations, the mean PIC value was more than 0.5 except in Assam (0.4815) and White Pekin (0.3725) ducks. The observed heterozygosity was the highest in Keeri ducks (0.5217) and lowest in White Pekin ducks (0.2766), while, the mean expected heterozygosity was the highest in Sanyasi (0.5628) and lowest in White Pekin (0.4038) ducks. The variations in the observed and expected number of alleles, differences in PIC of various microsatellite loci might be attributed to the genetic variability of the duck populations, number and type of microsatellite primers utilised for analysis and the genetic diversity of the duck breeds under study. Higher FST value indicates the substantial degree of breed differentiation among the studied duck populations.</div>

Therapeutic Evaluation of Sacubitril-valsartan (Arni) in Canine Dilated Cardiomyopathy

Genetic Diversity of Six Duck Populations in India