Published: 2024-08-28

Current status of coconut cultivation in Tien Giang province, Vietnam

Tri D. H. Nguyen, Phuong T. M. Nguyen, Thu N. Q. Thai, Thang Q. Luu, Thinh P. Pham, Chi T. K. Nguyen, Thuong A. Nguyen, & Dong T. H. Tran
Electronic version: 28 Aug 2024 | DOI: 10.52997/jad.4.02.2024
Abstract | PDF (139.3K)

Abstract

Coconut (Cocos nucifera L.) is one of the popular crops in Tien Giang province with many uses in food and industrial applications. Studying on the current status of coconut cultivation in Tien Giang province was carried out in three districts growing coconut including Cho Gao, Tan Phu Dong, and Chau Thanh. The secondary data were collected from the Statistics Department of Tien Giang province and Department of Agriculture and Rural Development of the investigated districts and primary data were collected via participatory interviews of 280 farming households. The results showed that there was a significant increase in the area used for coconut cultivation and harvesting from 2015 to 2022, averaging from 0.2 to 0.8 ha/household. The main form of cultivation was specialized farming with two popular varieties including coconut oil and coconut water. Coconut oil varieties had an average age of 10 to 20 years and their flowering time was from 3.5 to 5.0 years after planting, with an average annual yield of 31 to 90 fruits/tree. Coconut water varieties had an average age of 1 to 10 years and their flowering time was from 2 to 3 years after planting, with an average annual yield of 51 to 200 fruits/tree. The cost for coconut gardens during the business period ranged from 10 to 90 millions VND/ha per year, with profits averaging from 30 to 300 million VND/ha per year.

Survey on the presence of mycorrhizas on tomato roots in Lam Dong province and evaluation of its ability to symbiosis with crops

Ha T. N. Vo, Hien K. Pham, & Hung T. Huynh
Electronic version: 28 Aug 2024 | DOI: 10.52997/jad.4.01.2024
Abstract | PDF (1M)

Abstract

Using symbiotic mycorrhizal fungi (AM) to manage crop yield and soil health is essential to ensuring sustainable agricultural ecosystems. In this study, the AM’s presence and symbiotic structure in the soil and roots of tomato plants in Lam Dong area were investigated. Also, the ability of the most common AM genus in this area, Rhizophagus irregularis, with corn, rice, and tomato plants was evaluated. Tomato plants in the Lam Dong area had vesicular arbuscular mycorrhiza (VAM) symbiosis, with the symbiosis rate ranging from 53.1 to 81.3%. There were three types of symbiotic structures in VAM, wherein filamentous and vesicular structures predominated over dust. The genus Gigaspora dominated with 63.4%, followed by the genus Acaulospora (27.4%), the genus Glomus (9.7%), and spores from other unnamed genera (1.9%). When five spores of the genus Gigaspora were inoculated into the growing substrate at the stage of the formation of two true leaves, they showed good symbiosis with the roots of corn and tomato plants and had the best proliferation rate. On the other hand, Rhizophagus irregularis had weak synergy with all three plant types (corn, tomato, and rice).

Investigation of urologic diseases in dogs in Ho Chi Minh City, Vietnam

Oanh T. H. Bui, Khang H. Pham, Khanh N. Dinh, Thuc T. Nguyen, & Thuong T. Nguyen
Electronic version: 28 Aug 2024 | DOI: 10.52997/jad.4.05.2024
Abstract | PDF (578.2K)

Abstract

The study was conducted to evaluate urologic diseases in dogs in Ho Chi Minh City, from June 2022 to September 2022. The cases were collected based on medical history, physical examination and subclinical diagnosis. A total of 591 dogs surveyed, there were 87 cases which related to urinary system prolems, including 13 cases related to kidney and 74 cases related to lower urinary tracts. The common urologic diseases were cystitis with 37 cases (42.53%), followed by 29 cases of cystolith (33.33%), 5 cases of nephrolith (5.75%) and 5 cases of bladder polyps (5.75%). Female dogs had a higher proportion than male dogs (72.41% in female and 27.59% in male). Dog breeds did not affect the urologic diseases prevalence, with 68.97% in foreign dog breeds and 31.03% in domestic dog breeds. The age group 4-7 year-old accounted for 25%, which was the highest in all age groups. Meanwhile, it was just 3.33% in puppy under 1 year-old group. The common clinical signs were haematuria (21 cases), frequent urination (19 cases), and anorexia (18 cases) with 20.79%, 18.81% and 17.82%, respectively. There were 68 cases treated with drug therapy and 19 cases treated with both drug therapy and surgery. Results of blood physiological and biochemical indocators which related to urological diseases were creatinine (1.63 mg/dL), urea nitrogen huyết (47.55 mg/dL), aspartate transaminase (150.60 U/L) and alanine aminotransferase (115.80 U/L). The increased CK (617.30 U/L) showed that dogs with urological problems also had muscular and cardiac problems. The most common diagnosic imaging methods were ultrasonography and radiography.

Fattening of mud crab (Scylla paramamosain) in a recirculating tank system with different salinities

Bac V. Nguyen, Tuyen B. Cao, & Vu H. Le
Electronic version: 28 Aug 2024 | DOI: 10.52997/jad.4.04.2024
Abstract | PDF (371.9K)

Abstract

Mud crab (Scylla paramamosain) is one of the important species for aquaculture. The experiment was conducted at Ca Mau Community College to develop a mud crab fattening process in a recirculating tank system and to diversify aquaculture models in the Mekong Delta. In this experiment, mud crabs were reared at different salinities of 5, 15, 25, and 35‰ with three replicates for each treatment. Early gravid female crabs were stocked at 20 individuals/m2 in 200 L tanks linked with biofilters. Mud crabs were fed with trash fish at 3% of body weight daily. After 33 days of rearing, the results showed that the survival rates of full-gravid crabs in the treatments with salinities of 5‰, 15‰, 25‰, and 35‰ were 54.3%, 64.8%, 95.8%, and 91.5%, respectively. The daily weight gain, specific growth rate & gonadosomatic index of crabs in treatments ranged from 0.51 - 0.60 g/day, 0.17 - 0.20%/day, and 7.67 - 8.87%, respectively. However, there were no significant differences in these parameters among treatments (P > 0.05). The ovary weight (from 19.33 to 28.67 g) and the ratio of weight of ovary to hepatopancreas (from 147.22 to 220.24%) of crabs among treatments increased significantly with culture time, but were not significantly different (P > 0.05). Generally, the present study revealed that mud crab fattening at the salinity of 25‰ gave the best profit. These findings significantly contribute to improving technical processes for fattening of mud crabs reared in recirculating systems.

Determination of transducer types and frequencies in gonadal ultrasound of striped catfish Pangasianodon hypophthalmus (Sauvage, 1878)

Hoa P. Nguyen, Van T. B. Nguyen, Trong T. Tran, Linh N. T. Bui, & Hien T. T. Nguyen
Electronic version: 28 Aug 2024 | DOI: 10.52997/jad.4.03.2024
Abstract | PDF (2.4M)

Abstract

Ultrasound images can be utilized as a non-invasive method for the sex determination of striped catfish Pangasianodon hypophthalmus (Sauvage, 1878) for future breeding in a reproductive program. Striped catfish of various sizes were examined for gonads using an ultrasound machine. The results showed that for striped catfish less than 3 kg, a micro convex probe (5.0 MHz frequency), convex probe (3.5 - 5.0 MHz frequency), and linear probe (5.0 MHz frequency) could be used to examine gonads in ventral fish position. In a comprehensive examination of both  ovaries, convex and micro convex probes gave high-potential ultrasound images but could not identify their testis. In the case of sizeable striped catfish over 3 kg, using the convex probe (3.5 - 5.0 MHz frequency) and micro convex (5.0 MHz frequency) resulted in the best ultrasound images of ovaries. When the fish were at the stage of sexual maturity, it was possible to distinguish between the ovaries and the testis on ultrasound images.

Assessing and zoning economic damage risk of the inundation in Thu Duc city on the period 2021 - 2022

Hung V. Bui, & An T. Nguyen
Electronic version: 28 May 2024 | DOI: 10.52997/jad.4.06.2024
Abstract | PDF (618.5K)

Abstract

Thu Duc city, a sub-city under the administration of Ho Chi Minh City, was established in 2020 through the merging of three districts (Thu Duc District, District 2, and District 9). Thu Duc city has faced extensive urban flooding caused by rainfall and high tides. The impacts of urban flooding cause many adverse effects on people living in the area. To address these challenges, a survey was conducted focusing on flooding (7 parameters) and subsequent damages (17 components), both direct and indirect. This survey and assessment of the economic damage incurred by the residents of Thu Duc city covered the period from 2021 to 2022. The results of the study showed that the distribution of inundation, economic damage level and risk were concentrated in densely populated areas and riverside areas. Therefore, the study contributed valuable data and assessment results of damage caused by flooding for the urban management agencies of Thu Duc city.