Water is the most essential nutrient for poultry and livestock. Birds consume more water than feed. Water plays an important role in regulating body temperature and is a component of many basic chemical reactions. Besides all these meritorious property, water is one of the mediums that spread bacterial and viral diseases in poultry. Acid LAC W is an improved version of Acid LAC™ liquid, which is formulated to decontaminate viral as well as bacterial contaminations in drinking water. The present study was conducted to establish the antiviral activity of a novel formulation, Acid LAC W Liquid with compound X on poultry viruses, which can be transmitted by drinking water. There are two categories of viruses, Enveloped and Non – Enveloped. In former, the New Castle Disease Virus (NDV) and in latter, Infectious Bursal Disease Virus (IBD) were taken as model for the present study.
MATERIALS AND METHODS
Acid LAC W was formulated by incorporating compound X in the Acid LAC liquid at a specific concentration to give the antiviral property. The efficacy on Enveloped virus was tested on NDV by assessing Hemagglutination (HA) activity, Mean Death Time (MDT) and Embryo Lethal Dose (ELD50).
The efficacy on Non enveloped viruses was tested against IBD by assessing the Embryo Infective Dose (EID50)
RESULTS AND DISCUSSION
The HA activity of control and treatment groups are shown in Table 1.These results indicates that particular concentration of compound X in the final concentration of drinking water with 30 minutes contact time effectively made the ND virus to loose its Hemagglutination (HA) property. The loss of HA property might be due to the alteration of Hemagglutinin and Neuraminidase (HN) protein or on the envelope, which bears the HN glycoprotein, by the compound X in the formulation. The HN protein is responsible for the ND virus to attach on the host cell receptor containing Sialic acid (Bousse et al, 2004). This finding suggests that the ND virus lost its infectivity after treating with the formulation containing Compound X.Table 1. Hemagglutination Activity – NDV
|Hemagglutination Titre (Log2 HA units/50µl)|
The results of MDT are given in Fig.1. The MDT results clearly indicate that the Acid LAC W formulation made the virus to loose its infectivity and virulence at the recommended dose level. The MDT is the ideal method to type the ND virus (Khadzhiev, 1987). In this study the results of MDT strongly suggests that the virus lost its virulence and infectivity after treating with Acid LAC W.
Fig 1. Mean Death Time
Fig. 2 Embryo Lethal Dose
The results of ELD50 are shown in Fig 2. The ELD 50 results are also reflecting the same trend of HA and MDT. These promising results on NDV can directly be extrapolated to dreadful Avian Influenza because both virus share common physico - chemical properties.
The EID 50 is measured to find out the efficacy of novel Acid LAC W on Non – Enveloped poultry viruses. The results are shown in Fig. 3. The infective dose of the virus treated with Acid LAC W is less when compared to the control virus. This finding implies that this formulation has also got effect on Non-Enveloped viruses, though the efficacy is not on par with enveloped viruses.
Fig.3 Embryo Infective Dose
The results obtained in present study and earlier research works are highly encouraging that the novel formulation of Acid LAC W is better than Acid LAC with antiviral property.
1.The incorporation of compound X at a specific level in drinking water through Acid LAC W renders virucidal effect on Enveloped and Non Enveloped poultry viruses.
2.The New Castle Disease Virus (NDV) is taken as a model for enveloped poultry virus because the results can in-directly be correlated with Avian Influenza due to close structural similarity. The efficacy of Acid LAC W on this virus was assessed by HA activity, MDT and ELD 50 and found to have highly significant antiviral activity.
3.The model taken for Non-Enveloped poultry virus was Infectious Bursal Disease Virus (IBDV). The efficacy of Acid LAC W on this virus was assessed by Embryo Infective Dose (EID 50) and found to be statistically significant antiviral activity.
4.This research established that the Acid LAC W would not only render gut acidification property but also the complete spectrum of drinking water sanitization by possessing efficacy against a broad – spectrum of bacterial and viral pathogens.
Bousse Tl, Taylor G, Krishnamurthy S, Portner A, Samal SK, Takimoto T. Biological significance of the second receptor binding site of Newcastle disease virus hemagglutinin-neuraminidase protein. J Virol. 2004 Dec; 78(23): 13351- 5.
Khadzhiev G. Typing of Newcastle virus isolates by mean death time of chickens in the cloacal test. Vet Med Nauki. 1987; 24(5): 16-26.