Clinical and haematological alterations in foot and mouth disease virus naturally-infected domestic water buffaloes in Vietnam

DAM VAN P1,2_{., BUI TRAN ANH D}1_{., DESMECHT D}2_.

1. _{Department of Pathology, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, Vietnam.} 2. _{Department of Pathology and Autopsy, FARAH,} ULiège, Liège – Belgium.

The 4th FARAH

13 October 2017, Liège - Belgium

Clinical and haematological alterations in foot and mouth disease

virus naturally-infected domestic water buffaloes in Vietnam

- FMDV-infected buffaloes were confirmed by both clinical examination and RT-PCR using primers: FMDV-VP1R: CATGTCYTCYTGCATCTGGTT and FMDV-AS1F:

GCGSTHRYYCACACAGGYCCGG to detect the virus in swab samples.

- Blood samples were collected from jugular veins from 30 infected animals (20 female and 10 male buffaloes) ranging from 2 to 5 years old during an acute onset of FMD.

- Hematology and blood chemistry were identified by using a 32-parameter hematology analyzer – Pentra DF Nexus and a DxC AU 700 automated chemistry analyzer.

-  Statistical analysis was done using GraphPad Prism® version 5.0 software (California, USA). One-way analysis of variance (ANOVA) followed by Newman–Keuls posthoc test was used to compare data sets between healthy and infected buffaloes. Statistically significant at a value of p < 0.05.

METHODS

ABSTRACT

Foot and mouth disease (FMD) has been one of the most important epizootic diseases in several cloven-hoofed animals including buffaloes, causing severe economic losses in Vietnam. This study aimed at observing clinical indicators, physiological parameters, haematological and blood chemistry values of 30 buffaloes naturally infected with FMD virus (FMDV). The study was undertaken from January 2015 to February 2016 in Hanoi, Vietnam. Results show that buffaloes infected with FMDV displayed significantly higher fever, increased respiratory rate and increased heart frequency compared to healthy animals. Moreover, FMDV-infected animals always showed high fever and vesicular stomatitis, often showed edging nail congestive inflammation and, sometimes only, blisters on the nipple. Haematological indicators showed that FMDV-infected buffaloes were dehydrated (increased total protein). Besides, infected animals also underwent anaemia as mean c o r p u s c u l a r h a e m o g l o b i n a n d m e a n corpuscular haemoglobin concentrations were plummeted. Total white blood cell count plummeted too, especially the number and proportion of neutrophils. Meanwhile, the number and proportion of lymphocytes sharply increased compared to healthy animals. Infected buffaloes also displayed signs of liver and heart damages as judged by an increase in concentration of AST and ALT, while there was not renal damage since creatinine concentration remained stable.

_BACKGROUND

vulnerable to FMD

Buffaloes at Cho U (Do Luong, Nghe An) – the most dynamic buffalo market in southwest Asia

FMD epidemiological map 2015 (source: Division of epidemiology, Department of animal health)

OBJECTIVE

1)  To identify clinical symptoms in FMDV-infected buffaloes;

2)  To identify alterations in hematology of FMDV-infected buffaloes;

3)  To identify alterations in some blood chemical parameters of FMDV-infected buffaloes.

RESULTS

Diarrhoea Sores and blisters on feet

vesicles on the teats

Figure 1: Common clinical symptoms of FMDV-infected buffaloes

Data was presented in percentage of FMDV-infected animals manifesting with the clinical symptoms (n = 30 FMDV-infected buffaloes). 37.16 23.2 40.6 38.5 40.5 52.3 0 10 20 30 40 50 60 70

Body temperature (oC) Respiratory rate (breath/ min)

Heart rate (beat/min) Healthy buffaloes (n=5)

FMDV-infected buffaloes (n=30)

* *

*

Figure 2: Body temperature, respiratory and heart rate of FMDV-infected buffaloes

Data was presented in mean ± SD. Asterisks indicate the significant difference compared to healthy group (p< 0,05).

RESULTS (continued)

RESULTS (continued)

Figure 3: Alterations of red blood cells in FMDV-infected buffaloes

Data was presented in mean ± SD. Asterisks indicate the significant difference compared to healthy group (p< 0,05).

6.57 12.41 35.61 54.89 19.17 33.64 18.40 7.48 11.85 35.58 48.50 16.08 33.28 21.30 0 10 20 30 40 50 60 70 RBCs (tetra/L) Hb (g/dL) HCT (%) MCV (fL) MCH (pg) MCHC (g/dL) RDW (%) Healthy buffaloes (n=5) FMDV-infected buffaloes (n=30) * * * * * * *

Figure 4: White blood cell counts in FMDV- infected buffaloes

Data was presented in mean ± SD. Asterisks indicate the significant difference compared to healthy group (p< 0,05).

12.28 5.44 0.03 0.12 5.08 1.61 9.52 2.39 0.04 0.18 6.77 0.14 0 2 4 6 8 10 12 14 16 Tota l Neutr ophi l Eosi noph il Basophils Lym phoc yt Mono cyte s Healthy buffaloes (n=5) FMDV-infected buffaloes (n=30) * * * * 163.98 42.10 126.05 197.59 45.57 129.49 0 50 100 150 200 250 300 350

AST 0r GOT (U/l) ALT or GPT (U/l) Creatinine (mmol/L)

Healthy buffaloes (n=5) FMDV-infected buffaloes (n=30)

Figure 6: Blood Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and creatinine of

FMDV-infected buffaloes

The concentrations were presented in mean ± SD. Asterisks indicate the significant difference compared to healthy group (p< 0,05).

CONCLUSIONS

2) Hematology of the infected buffaloes was altered obviously. Proportion of lymphocytes increased sharply while there were significant drop in all of other white blood cell counts. Red blood cells was also altered obviously in some parameters. Cell counts, hematocrit, mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width (RCD) were increased significantly, meanwhile hemoglobin (Hb), mean corpuscular volume (MCV) and mean corpuscular Hemoglobin (MCH) decreased obviously.

3) AST and ALT of the infected buffaloes were also increased significantly, while blood creatinine remained stable.

Day 15th of onset: lesions in mount cavity were healed, the animal were almost recovered. Day 5th to 6th of onset: vast detachment of gums (A) and tongue membranes causing bloody slobbering (B).

A B

Day 3rd to 4th of onset: sore and blister on feet caused the patience refused to stand and walk

Day 3rd to 4th of onset: slobbering and smacking lips (A), sore and blister on feet (B)

A B

CLINICAL ALTERATIONS IN FMDV-INFECTED BUFFALOES

Free grazing buffaloes in

Hanoi, Vietnam Buffalo: an important means for agricultural production

Un-classified serotype

Figure 5: Proportional white blood cells of FMDV-infected buffaloes

Data was presented in mean ± SD (%). Asterisks indicate the significant difference compared to healthy group (p< 0,05). HAEMATOLOGICAL AND BLOOD CHEMISTRIAL ALTERATIONS IN FMDV-INFECTED BUFFALOES

44.92 0.27 1.10 40.32 13.39 25.59 0.46 1.91 70.61 1.44 0 10 20 30 40 50 60 70 80 90 Neutrophils

% Eosinophils (%) Basophils (%) Lymphocytes % Monocytes %

Healthy buffaloes (n=5) FMDV-infected buffaloes (n=30) * * * * *