• Parasites, Hosts and Diseases
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• v.51 no.5
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• pp.589-594
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• 2013

In intestinal helminth infections, Th2 immune respones are generally associated with mucin secretion for worm expulsion from the host intestine. In particular, IL-4 and IL-13 are the important cytokines related with intestinal mucus production via STAT6 signalling in nematode infections. However, this perspective has never been studied in Gymnophalloides seoi infection. The present study aimed to observe the STAT6 signalling and cytokine responses in C57BL/6 mice, a mouse strain resistant to infection with this trematode. The results showed that worm expulsion occurred actively during days 1-2 post-infection (PI), when goblet cells began to proliferate in the small intestine. The STAT6 gene expression in the mouse spleen became remarkable from day 2 PI. Moreover, G. seoi infection induced a significant increase of IL-13 from day 4 PI in the spleen of infected mice. Our results suggested that goblet cell hyperplasia and worm expulsion in G. seoi-infected mice should be induced by STAT6 signalling, in which IL-13 may be involved as a dominant triggering cytokine.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.1
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• pp.72-81
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• 2009

Eight Black Belly rams (45.2 kg) fitted with permanent ruminal cannulae were used in a 2${\times}$2 factorial design to determine the effects of feeding frequency and regrowth age on intake and digestion. Rams were fed with 21- or 35-day old fresh pangola grass offered ad libitum two or four times a day. Irrespective of the regrowth age, there was a tendency for intake to be positively correlated with increase in meal frequency. Differences were not significant (p>0.25). Significant effects of meal frequency were observed in NDF and ADF total tract digestibility of the 35-day grass which decreased as the number of meals increased. Meal frequency had no visible effect on feeding behaviour. Total rumen content increased when animals were fed twice a day as opposed to four times a day. Similarly, an accumulation of small and very small particles was observed in the rumen of rams fed twice a day in comparison with those fed four times a day. These results suggest that studies of digestive dynamics performed at a steady state are not representative of the rumen loading observed in farm rams which have two important peaks of meal.

• Parasites, Hosts and Diseases
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• v.46 no.2
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• pp.65-70
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• 2008

Artemisinin-based combination therapy (ACT) is currently promoted as a strategy for treating both uncomplicated and severe falciparum malaria, targeting asexual blood-stage Plasmodium falciparum parasites. However, the effect of ACT on sexual-stage parasites remains controversial. To determine the clearance of sexual-stage P. falciparum parasites from 342 uncomplicated, and 217 severe, adult malaria cases, we reviewed and followed peripheral blood sexualstage parasites for 4 wk after starting ACT. All patients presented with both asexual and sexual stage parasites on admission, and were treated with artesunate-mefloquine as the standard regimen. The results showed that all patients were asymptomatic and negative for asexual forms before discharge from hospital. The percentages of uncomplicated malaria patients positive for gametocytes on days 3, 7, 14, 21, and 28 were 41.5, 13.1, 3.8, 2.0, and 2.0%, while the percentages of gametocyte positive severe malaria patients on days 3, 7, 14, 21, and 28 were 33.6, 8.2, 2.7, 0.9, and 0.9%, respectively. Although all patients were negative for asexual parasites by day 7 after completion of the artesunate-mefloquine course, gametocytemia persisted in some patients. Thus, a gametocytocidal drug, e.g., primaquine, may be useful in combination with an artesunate-mefloquine regimen to clear gametocytes, so blocking transmission more effectively than artesunate alone, in malaria transmission areas.

• Parasites, Hosts and Diseases
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• v.42 no.2
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• pp.85-89
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• 2004

Cryptosporidium parvum oocysts were isolated from a child suffering from acute gastroenteritis and successfully passaged in a calf and mice (designated hereafter SNU-H1) in the Republic of Korea; its molecular genotype has been analyzed. The GAG microsatellite region was amplified by a polymerase chain reaction (PCR), with a 238 base pair product, which is commonly displayed in C. parvum. The isolate was shown to be a mixture of the genotypes 1 (anthroponotic) and 2 (zoonotic). To study its infectivity in animals, 2 calves and 3 strains of mice were infected with the SNU-H1; in these animals, the propagation of both genotypes was successful. In immunosup-pressed (ImSP) BALB/c and C57BU6 mice the number of oocysts decreased after day 10 post-infection (PI); but in ImSP ICR mice, they remained constant until day 27 PI. The results show that both the C. parvum genotypes 1 and 2 can be propagated in calves and ImSP mice.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.127-131
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• 2002

The OJIP transients were investigated from leaves of Crinum asiaticum var. japonicum, Osmanthus insularis, Chloranthus glaber and Asplenium antiquum, in order to screen the indicators for quantification of environmental stresses and to apply them to the plant vitality test. The obvious diurnal changes or OJIP transients were found in Crinum asiaticum var. japonicum, Osmanthus insularis growing in sunny habitats, showing lower Fp and higher Fo in day time. The values of SF $I_{no}$ and P $I_{NO}$ increased dramatically in day time in leaves of Crinum asiaticum var. japonicum, Osmanthus insularis, and Asplenium antiquum. Although the value of RC/CS decreased slightly in day time in leaves of 4 tropica $l_tropical plants, the obvious diurnal changes or OJIP transients were not seen in winter, suggesting that tropica $l_tropical paints used in this research seemed to be irreversibly damaged in winter. However, the values of ETo/RC and Ψo/(1-Ψo) increased significantly in leaves of Crinum asiaticum var. japonicum, indicating that ETO/RC and Ψo/(1-Ψo) were useful as indicator parameters for scensing of low temperature.ature.

• Parasites, Hosts and Diseases
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• v.44 no.4 s.140
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• pp.295-302
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• 2006

Liver function tests were peformed in 61 vivax, 54 malariae and 15 ovale malaria patients who were admitted to Bangkok Hospital for Tropical Diseases between 2001 and 2004. The objective of the study was to evaluate changes in hepatic biochemical indices before and after treatment with artemisinin derivatives. On admission and prior to treatment, hepatic dysfunction was found among the 3 groups. Serum liver function tests and physical examinations were peformed weekly during the 28-day follow-up period. Initially elevated serum bilirubin and diminished albumin returned to normal within 2 weeks of treatment. Serum alkaline phosphatase and aminotransferases returned to within normal limits within 3 weeks. We conclude that patients with Plasmodium vivax, P. malariae and p. ovate infections had slightly elevated serum bilirubin, aminotransferase and alkaline phosphatase levels, and hypoalbuminemia. These minor abnormalities returned to normal within a few weeks after treatment with therapies based on artemisinin derivatives.

• Animal Bioscience
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• v.37 no.4
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• pp.576-590
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• 2024

Objective: The objective of this study was to identify genes associated with 305-day milk yield (MY) and fat yield (FY) that also influence the adaptability of the Thai multibreed dairy cattle population to tropical conditions. Methods: A total of 75,776 imputed and actual single nucleotide polymorphisms (SNPs) from 2,661 animals were used to identify genomic regions associated with MY and FY using the single-step genomic best linear unbiased predictions. Fixed effects included herd-year-season, breed regression, heterosis regression and calving age regression effects. Random effects were animal additive genetic and residual. Individual SNPs with a p-value smaller than 0.05 were selected for gene mapping, function analysis, and quantitative trait loci (QTL) annotation analysis. Results: A substantial number of QTLs associated with MY (9,334) and FY (8,977) were identified by integrating SNP genotypes and QTL annotations. Notably, we discovered 17 annotated QTLs within the health and exterior QTL classes, corresponding to nine unique genes. Among these genes, Rho GTPase activating protein 15 (ARHGAP15) and catenin alpha 2 (CTNNA2) have previously been linked to physiological traits associated with tropical adaptation in various cattle breeds. Interestingly, these two genes also showed signs of positive selection, indicating their potential role in conferring tolerance to trypanosomiasis, a prevalent tropical disease. Conclusion: Our findings provide valuable insights into the genetic basis of MY and FY in the Thai multibreed dairy cattle population, shedding light on the underlying mechanisms of tropical adaptation. The identified genes represent promising targets for future breeding strategies aimed at improving milk and fat production while ensuring resilience to tropical challenges. This study significantly contributes to our understanding of the genetic factors influencing milk production and adaptability in dairy cattle, facilitating the development of sustainable genetic selection strategies and breeding programs in tropical environments.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.3
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• pp.183-186
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• 1990

Monensin administered as a slow release capsule to Droughtmaster steers grazing mixed pastures containing Stylosanthes hamata or grass pastures fertilized with N, had no effect on growth rate over 111 day period. Monensin significantly increased the level of propionic acid (p<0.001) and decreased the level of butyric acid (p<0.01) in the rumen. The lack of response to monesin was partly attributed to the poor pasture conditions and growth rate of the steers during part of the experimental period. An implant of oestradiol improved growth rates during the period of poor forage quality and in the subsequent 56 days when pastures were of high quality following rain. Mean growth rates over the entire 157 days for control, monensin and monensin/oestradiol treatments were 0.37, 0.37 and 0.50 kg/d respectively. It was concluded that when pasture conditions are sufficient only for the maintenance of liveweight, production can be improved by an oestradiol implant but not by feeding an ionophore such as monensin.

• Parasites, Hosts and Diseases
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• v.45 no.4
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• pp.267-271
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• 2007

Theileria annulata, a protozoan parasite of cattle and domestic buffaloes, is transmitted by ticks of the genus Hyalomma, and causes a disease named Mediterranean or tropical theileriosis. In this research 50 cattle naturally infected with Theileria annulata were treated with the extract of the plant Peganum harmala. The treatment was continued for 5 days, the dose of the extract being 5 mg/kg per day. After the treatment, 39 cattle responded to the treatment and recovered, but 11 did not respond to the treatment and died. The recovery rate of animals treated with the extract of the plant Peganum harmala was 78%.

• Parasites, Hosts and Diseases
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• v.44 no.3
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• pp.221-228
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• 2006

We conducted a study to compare the safety and tolerability of anti-relapse drugs elubaquine and primaquine against Plasmodium vivax malaria. After standard therapy with chloroquine, 30 mg/kg given over 3 days, 141 patients with P. vivax infection were randomized to receive primaquine or elubaquine. The 2 treatment regimens were primaquine 30 mg once daily for 7 days (group A, n = 71), and elubaquine 25 mg once daily for 7 days (group B, n = 70). All patients cleared parasitemia within 7 days after chloroquine treatment. Among patients treated with primaquine, one patient relapsed on day 26; no relapse occurred with elubaquine treatement. Both drugs were well tolerated. Adverse effects occurred only in patients with G6PD deficiency who were treated with primaquine (group A, n = 4), whose mean hematocrit fell significantly on days 7,8 and 9 (P= 0.015, 0.027, and 0.048, respectively). No significant change in hematocrit was observed in patients with G6PD deficiency who were treated with elubaquine (group B, n = 3) or in patients with normal G6PD. In conclusion, elubaquine, as anti-relapse therapy for P. vivax malaria, was as safe and well tolerated as primaquine and did not cause clinically significant hemolysis.