Azila Abdullah - Academia.edu (original) (raw)

Papers by Azila Abdullah

Research Square (Research Square), Apr 22, 2024

Department of Fisheries Malaysia, Dec 1, 2018

Veterinary World

Background and Aim: One of the emerging viral diseases in freshwater fish is Tilapia lake virus (... more Background and Aim: One of the emerging viral diseases in freshwater fish is Tilapia lake virus (TiLV), which infects all stages of fish and results in mass mortalities. Previously, a TiLV case was detected in the wild environment in Malaysia that involved tilapia and tinfoil barb. Hence, this study aimed to determine the presence of TiLV in wild tilapia (Oreochromis niloticus) as well as tinfoil barbs (Barbonymus schwanenfeldii) at the similar lake after the initial outbreak in year 2017. Materials and Methods: Both fish species were sampled from this lake at a month interval for two years and subjected to TiLV detection using reverse transcriptase-polymerase chain reaction and cell culture isolation. Concurrently, bacterial isolation and water quality measurements were performed to deduce their correlation with TiLV occurrence. Other wild fish species and mollusk were also occasionally sampled during the fish inventory activity at this lake. The fish's weight, length, and asso...

The epizootiology of disease problems in Lutjanus erythropterus (Crimson snapper) was conducted i... more The epizootiology of disease problems in Lutjanus erythropterus (Crimson snapper) was conducted in Pulau Langkawi Kedah, the northern state of Peninsular Malaysia, for a period of eight months until harvest due to reported continuous mortality of about 30% after two months introduction, incurring high economic loss. Infected fish was morbid, discoloured with haemorrhagic ulcers in dorsal areas and severe necrosis of caudal region. Monthly sampling revealed multiple Vibrio infections with variable prevalence rate during grow-out stage as shown in Fig.1. Necropsy revealed abnormal liver, with cases of severe whitish nodules in kidney and spleen. The caudal peduncle area was soft and fluffy to touch, releasing yellowish exudates when cut. Histopathological diagnosis of the kidney, spleen and muscle using Grocott and Modified Ziehl Nelsen staining revealed red, long, thin and filamentous organisms in the granulomatous lesions suggestive of nocardiosis shown in Fig. 2. Further sampling o...

August, 2019

Background and Aim: Viral nervous necrosis (VNN) is a serious disease of several marine fish spec... more Background and Aim: Viral nervous necrosis (VNN) is a serious disease of several marine fish species. VNN causes 100% mortality in the larval stages, while lower losses have been reported in juvenile and adult fish. This study aimed to detect the occurrence of VNN while identifying its associated risk factors and the genotypes of its causative agent in a hybrid grouper hatchery in Malaysia. Materials and Methods: A batch of newly hatched hybrid grouper fry (Epinephelus fuscoguttatus X Epinephelus lanceolatus) were followed from the larval stage to market size. Samples of the hybrid groupers, water, live feed, and artificial fish pellets were collected periodically from day 0 to 180 in the hybrid grouper hatchery. Reverse transcription-polymerase chain reaction (RT-PCR) and nested PCR amplifications were carried out on VNN-related sequences. The phylogenetic tree including the sampled causative agent of VNN was inferred from the coat protein genes from all known Betanodavirus species...

Pertanika J. Trop. …, 2012

Aquaculture International, 2019

Kajian ini merupakan satu kajian deskriptif untuk meninjau kemahiran berkomunikasi dalam pembelaj... more Kajian ini merupakan satu kajian deskriptif untuk meninjau kemahiran berkomunikasi dalam pembelajaran di kalangan pelajar tahun akhir Jabatan Pendidikan Teknikal dan Kejuruteraan, Fakulti Pendidikan UTM sebagai persediaan bakal guru. Seramai 118 orang pelajar perdana tahun akhir dari Jabatan Pendidikan Teknikal dan Kejuruteraan, Fakulti Pendidikan telah dipilih sebagai sampel kajian. Kajian dijalankan dengan menggunakan satu set soal selidik yang diedarkan kepada pelajar. Data yang diperolehi dianalisis dengan menggunakan perisian Statistical Packages for Social Sciences (SPSS) 11.5 For Windows. Hasil analisis mendapati, majoriti responden mengakui bahawa pada persepsi mereka, kemahiran komunikasi adalah penting bagi diri mereka sebagai persediaan seorang guru. Manakala tahap penguasaan responden dalam kemahiran bertutur dan kemahiran mendengar juga berada pada tahap tinggi. Kajian ini juga mendapati tahap penguasaan responden dalam kemahiran berkomunikasi adalah pada tahap yang sed...

Veterinary World, 2022

Fish diseases have a significant negative influence on the Malaysian aquaculture industry. Since ... more Fish diseases have a significant negative influence on the Malaysian aquaculture industry. Since the 1980s, the sector has grown in size, which has resulted in a rise in the prevalence of infectious outbreaks affecting both freshwater and marine cultured fish species. Demand for commercially available fish vaccinations is predicted to increase as infectious disease outbreaks continue to occur. In Malaysia, aquaculture vaccine research and development (R&D) are still in its infancy, with most efforts concentrating on producing vaccines against bacterial infections, most notably streptococcosis, vibriosis, and motile Aeromonas septicemia. Despite several attempts, no homegrown vaccine has been effectively introduced into the manufacturing pipeline to date. At the moment, only three imported aquatic vaccines have received full permission, a far cry from the 314 and 60 vaccines licensed in the poultry and porcine industries, respectively. This review will describe recent findings regard...

Veterinary World, Apr 27, 2022

Materials and Methods: Both fish species were sampled from this lake at a month interval for two years and subjected to TiLV detection using reverse transcriptase-polymerase chain reaction and cell culture isolation. Concurrently, bacterial isolation and water quality measurements were performed to deduce their correlation with TiLV occurrence. Other wild fish species and mollusk were also occasionally sampled during the fish inventory activity at this lake. The fish's weight, length, and associated clinical signs were noted throughout the entire study period.

Results: Mortality was not observed throughout the whole study period, and results indicated a moderate to high prevalence of TiLV infection in both tilapia and tinfoil barbs. There was no correlation between TiLV infection with the isolation rate of opportunistic bacteria such as Aeromonas spp., Plesiomonas spp., and Edwardsiella spp. in the study site. At the same time, the Pearson correlation test revealed a moderate negative correlation between the water pH with the presence of TiLV (R=–0.4472; p<0.05) and a moderate positive correlation between the water iron content with the monthly detection of Aeromonas spp. in wild tilapia. This is contrary to tinfoil barbs, where there was a moderate negative correlation between the water iron content with the monthly isolation of Aeromonas spp. (R=–0.5190; p<0.05). Furthermore, isolation of TiLV on cell culture-induced viral invasion was resulted in the cytopathic effects.

Conclusion: Our results suggest that the wild fish may harbor TiLV for an extended period following a massive die-off event in 2017 without any obvious clinical signs and mortality. The persistency of viruses in the wild may need continuous and effective control as well as prevention strategies.

A series of experiments were conducted to evaluate barley fodder (BF) as a feed for ruminants. Ba... more A series of experiments were conducted to evaluate barley fodder (BF) as a feed for ruminants. Barley seeds were grown in a specially designed and controlled environment cabin at 15 - 18°C. The first experiment was conducted to germinate barley seeds from day 0 (dO) to day 10 (dIO, n=ll) and samples were collected daily for chemical composition analysis. In the second experiment, the rumen simulation technique (RUSITEC) was used to measure the in vitro dry matter (DM) and crude protein (CP) digestibility and the volatile fatty acids (VF A) produced by BF at different times. The nylon bag technique was also used to measure the DM degradability of BF in the rumen of cattle at 2, 4, 8, 12, 24 and 48 hours. The third experiment on the intake and digestibility of eight-day old BF was measured by an in vivo technique, using four bucks. The fourth experiment involved the measurement of rumen fluid parameters (pH, ammonia and VFA) in three rumen fistulated bucks that were fed on eight-day o...

Marine fish has been shown to be susceptible to parasites, bacteria, viral and fungal infections.... more Marine fish has been shown to be susceptible to parasites, bacteria, viral and fungal infections. In marine environment, Vibrio species are commonly found and can lead to an infection known as vibriosis. Vibriosis causes bloody lesion to the fish muscles and extensive haemorrhage to the internal organs to the marine fish. It is a zoonotic disease causing septicaemia, gastroenteritis and necrotising fasciitis following exposure of wounds to contaminated sea water or fish. In this study, we examined and sampled tiger grouper (Epinephelus fuscoguttatus ) cultured in deep sea cages until harvest time. The sampling period was started from February to August 2014, following more than 50% mortality. Clinical signs were noted and compared with the microbiological isolations, especially Vibrio spp. and specific viral isolations. Histopathology changes and water quality parameters were also noted. Fish infected with vibriosis showed signs of body ulcerations and haemorrhages of the fins and b...

This study investigates the prevalence, risk factors, and transmission of nervous necrosis virus ... more This study investigates the prevalence, risk factors, and transmission of nervous necrosis virus (NNV) in a hatchery producing hybrid grouper (Epinephelus lanceolatus × Epinephelus fuscoguttatus) fry. The eggs and sperm of giant grouper (GG) and tiger groupers (TG) that were collected for breeding purposes within the 12-month study period were sampled to detect NNV. At the same time, three breeding attempts of different NNV status of broodstocks, which were NNV-positive GG × NNV-positive TG, NNV-positive GG × NNV-negative TG and NNV-negative GG × NNV-negative TG were conducted. The produced hybrid grouper (HG) fry was then sampled at 5, 10, 20, 30, 40, 60, 90, and 120 days post-hatched to detect the presence of NNV. The fresh fish, live feed, and commercial fish pellet that were used to feed the broodstocks or HG fry throughout the study period were also sampled for NNV detection. The water’s physico-chemical parameters during each sampling were determined. The results revealed that...

Betanodavirus is known to cause mass mortality in many marine aquaculture fish species. In this s... more Betanodavirus is known to cause mass mortality in many marine aquaculture fish species. In this study, we detected the virus in four different marine aquaculture fish species in Malaysia. These included humpback grouper (Cromileptisaltivelis), brown marbled grouper (Epinephelusfuscoguttatus), Asian seabass (Latescalcarifer) and golden pompano (Trachinoltusblochii). Out of 246 fish specimens analyzed using RT-PCR, 60.98% detected infected by the virus. Histological pathological analysis showed extensive cell vacuolationin the brain and retina tissues of severely infected specimens. However, some of the fish specimens detected positive using RT-PCR did not exhibit cell vacoulation which indicate the carrier state of those specimens. The RT-PCR amplification method developed in this study was shown useful as biosecurity tool in monitoringBetanodavirus infection in aquaculture. Although the origin of Betanodavirus in Malaysia is difficult to ascertained, evidence showed that some infect...

Frontiers in Veterinary Science, 2016

Tropical life sciences research, 2013

The mass mortality of cobia (Rachycentron canadum) within 2-3 days was reported by 3 private farm... more The mass mortality of cobia (Rachycentron canadum) within 2-3 days was reported by 3 private farms in Bukit Tambun, Pulau Pinang, in February and March 2007. Only cobia with body weights of 3-4 kg were affected. Most diseased cobia swam on the surface and displayed flashing behaviour. All samples were positive for viral nervous necrosis (VNN) with low to medium levels of infection. Infestations by leeches (Zeylanicobdella arugamensis), body monogeneans (Benedenia sp.) and copepods (Caligus sp.) were also found, but no pathogenic bacteria were isolated. All water quality parameters monitored were within optimal ranges for culturing cobia. The main causes of high mortality in cobia remain unclear during the study. However, we believe that the mass mortality of cobia could be probably due to VNN infection and that the rate of mortality will increase further when cobia are subjected to aquaculture-related stresses (e.g., limited space). Traditional cages with a size of 2 (length) × 2 (w...