• Journal of Microbiology and Biotechnology
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• v.19 no.5
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• pp.511-519
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• 2009

A chimeric gene encoding enhanced green fluorescent protein (EGFP) and a S-layer protein from Lactobacillus brevis KCTC3102, and/or two copies of the Fe-binding Z-domain, a synthetic analog of the B-domain of protein A, was constructed and expressed in Escherichia coli BL21(DE3). The S-layer fusion proteins produced in a 500-1 fermentor were likely to be stable in the range of pH 5 to 8 and $0^{\circ}C$ to $40^{\circ}C$. Their adhesive property enabled an easy and rapid immobilization of enzymes or antibodies on solid materials such as plastics, glass, sol-gel films, and intestinal epithelial cells. Owing to their affinity towards intestinal cells and immunoglobulin G, the S-layer fusion proteins enabled the adhesion of antibodies to human epithelial cells. In addition, feeding a mixture of the S-layer fusion proteins and antibodies against neonatal calf diarrhea (coronavirus, rotavirus, Escherichia coli, and Salmonella typhimurium) to Hanwoo calves resulted in 100% prevention of neonatal calf diarrhea syndrome (p<0.01), whereas feeding antibodies only resulted in 56% prevention.

• Korean Journal of Veterinary Service
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• v.45 no.4
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• pp.337-342
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• 2022

Calf diarrhea is a major health concern in the livestock industry that requires accurate analysis for appropriate treatment. Dehydration and electrolyte imbalance are the most significant consequences of diarrhea in calves. Until now, the reference values of blood analysis of Hanwoo neonatal calves have not been well known. Recently, portable blood analyzers have made it possible to immediately analyze blood in the farm and provide suitable treatment for the patients. We analyzed electrolytes, blood urea nitrogen (BUN) and glucose in the blood of 179 Hanwoo neonatal calves, including 79 with diarrhea. These 179 calves were divided into 3 groups based on their age. Values of sodium (Na⁺ ) and glucose were significantly lower in diarrheic calves (1~30 days), while potassium (K⁺ ) and chloride (Cl^- ) values were higher in diarrheic calves (1~30 days). BUN values, which are closely related to dehydration due to diarrhea, increased in diarrheic calves of all ages. Therefore, these data can be used as reference values for blood analysis and treatment of healthy or diarrheic Hanwoo neonatal calves within 30 days of age.

• Korean Journal of Veterinary Service
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• v.17 no.1
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• pp.37-43
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• 1994

The rate of 58 neonatal calves in infection of Theileria sergenti was investigated in random samples on the farms located in Kyunggi, Chonbuk districts of Korea. 1. The criteria used in veryfying infection with T. sergenti included the detection of parasites by giemsa stain and acridine orange stain in the blood smear slides. 2. Further evidence of current or previous exposure to T. sergenti was based on demonstration of T. sergenti specific antibody and antigen by the western immunoblot and the directed immunofluorescent antibody test in the peripherial blood of the calves. 3. The prevalence rates were 35%, 50% in Kyunggi, Chonbuk provinces respectively and the overall prevalence in all the farms was 43.2％ by means of acridine orange stain. 4. The parasites that were observed in the peripherial blood of calves was showen surely by the western immunoblot to the characteristic 34KD antigen among the proteins of T. sergenti (Korean isolate). 5. And the antigen of the neonatal calves reacted at the very highest titer(1 : 2, 560) 6. These data highlight the significances of T. sergenti in the neonatal calf disease in Korea.

• Journal of Veterinary Science
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• v.25 no.5
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• pp.59.1-59.10
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• 2024

Importance: Despite advancements in herd management, feeding, and pharmaceutical interventions, neonatal calf diarrhea (NCD) remains a major global health concern. Bacteria, viruses, and parasites are the major contributors to NCD. Although several pathogens have been identified in the Republic of Korea (ROK), the etiological agents of numerous NCD cases have not been identified. Objective: To identify, for the first time, the prevalence and impact of Boosepivirus (BooV) on calf diarrhea in the ROK. Methods: Here, the unknown cause of calf diarrhea was determined using metagenomics We then explored the prevalence of certain pathogens, including BooV, that cause NCD. Seventy diarrheal fecal samples from Hanwoo (Bos taurus coreanae) calves were analyzed using reverse transcriptase and quantitative real-time polymerase chain reaction for pathogen detection and BooV isolate sequencing. Results: The complete genome of BooV was detected from unknown causes of calf diarrhea. And also, BooV was the most frequently detected pathogen (35.7%) among 8 pathogens in 70 diarrheic feces from Hanwoo calves. Co-infection analyses indicated that most BooV-positive samples were solely infected with BooV, indicating its significance in NCD in the ROK. All isolates were classified as BooV B in phylogenetic analysis. Conclusions and Relevance: This is the first study to determine the prevalence and molecular characteristics of BooV in calf diarrhea in the ROK, highlighting the potential importance of BooV as a causative agent of calf diarrhea and highlighting the need for further research on its epidemiology and pathogenicity.

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.665-671
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• 1993

The rate of 67 neonatal calves's infection of Theileria sergenti was investigated in random samples on the farms located in Kyeongki, Chonbuk and Jeju districts of Korea. The criteria used in verifying infection with T sergenti included the detection of parasites by giemsa's stain and acridine orange stain in the blood smear slides. Further evidence of current or previous exposure to T sergenti was based on the demonstration of T sergenti-specific antibody and antigen by the western immunoblot and the indirect immunofluorescence antibody test in the peripheral blood of the calves. The prevalence rates were 35%, 50% and 100% in Kyeongki, Chonbuk and Jeju provinces respectively and the overall prevalence in all the farms was 43.2% by means of acridine orange stain. The parasites that were observed in the peripheral blood of calves was shown surely by the western immunoblot to the characteristic 34KD antigen among the proteins of T sergenti (Korean Isolate). And the antibody of the neonatal calves reacted at the very highest titer(1 : >2,520). These data highlight the significance of T sergenti in the neonatal calf disease in Korea.

• Journal of Veterinary Science
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• v.25 no.3
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• pp.38.1-38.16
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• 2024

Importance: Deaths due to neonatal calf diarrhea are still one of the most critical problems of cattle breeding worldwide. Determining the parameters that can predict diarrhea-related deaths in calves is especially important in terms of prognosis and treatment strategies for the disease. Objective: The primary purpose of this study was to determine mortality rates and durations, survival status, and predictive prognosis parameters based on vital signs, hematology, and blood gas analyses in neonatal diarrheic calves. Methods: The hospital automation system retrospectively obtained data from 89 neonatal diarrheic calves. Results: It was found that 42.7% (38/89) of the calves brought with the complaint of diarrhea died during hospitalization or after discharge. Short-term and long-term fatalities were a median of 9.25 hours and a median of 51.50 hours, respectively. When the data obtained from this study is evaluated, body temperature (℃), pH, base excess (mmol/L), and sodium bicarbonate (mmol/L) parameters were found to be lower, and hemoglobin (g/dL), hematocrit (%), lactate (mmol/L), chloride (mmol/L), sodium (mmol/L) and anion gap (mmol/L) parameters were found to be higher in dead calves compared to survivors. Accordingly, hypothermia, metabolic acidosis, and dehydration findings were seen as clinical conditions that should be considered. Logistic regression analysis showed that lactate (odds ratio, 1.429) and CI^- (odds ratio, 1.232) concentration were significant risk factors associated with death in calves with diarrhea. Conclusions and Relevance: According to the findings obtained from this study, the determination of lactate and Cl^- levels can be used as an adjunctive supplementary test in distinguishing calves with diarrhea with a good prognosis.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.643-649
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• 2011

The objective of this study was to determine the effect of feeding direct-fed microbials (DFM) on the growth performance and prophylaxis of calf diarrhea during the pre-weaning period as an alternative to antibiotics. A multi-species DFM was formulated including three lactic acid bacteria (Lactobacillus salivarius Ls29, Pediococcus acidilactia Pa175, and L. plantarum Lp177), three Bacillus strains (B. subtilis T4, B. polymyxa T1 and SM2), one yeast, Saccharomyces boulardii, and a nonpathogenic E. coli Nissle 1917. Lactic acid bacteria and Bacillus strains were selected based on the antibacterial activity against various animal pathogens, especially pathogenic E. coli using agar diffusion methods in vitro. Test and control groups were fed milk replacer and calf starter supplemented with DFM ($10^9$ cfu each of eight species/d/head, n = 29) or with antibiotics (0.1% neomycin sulfate in milk replacer and Colistin 0.08% and Oxyneo 110/110 0.1% in calf starter, n = 15), respectively. Overall fecal score and the incidence rate of diarrhea were reduced in the DFM group compared to the antibiotics one. About 40% of calves in antibiotic group suffered from diarrhea while in DFM group only 14% showed diarrhea. There was no difference in the average daily gain and feed efficiency of two groups. The hematological levels of calves were all within the normal range with no significant difference. In conclusion, the feeding of multispecies DFM during the pre-weaning period could reduce calf diarrhea and there was no difference in the growth performance between the groups, thus showing the potential as an alternative to antibiotics.

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.864-871
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• 2021

Infectious calf diarrhea is one of the most significant diseases of neonatal calves. This study is conducted to identify the prevalence of pathogens in calf diarrhea for 2 years. A total of 544 feces samples from Korean native beef calves were obtained to investigate selected seven pathogens causing calf diarrhea: bovine rotavirus, bovine coronavirus, Cryptosporidium parvum, bovine viral diarrhea virus, Eimeria species, Escherichia coli K99, and Salmonella species. The presence of diarrhea, the number and species of detected pathogens, and the calves' ages were analyzed using various statistical methods depending on the case. Of the 544 calves, 340 calves (62.5%) had normal feces and 204 calves (37.5%) had diarrhea. The presence of pathogens was significantly associated with diarrhea (p < 0.01) and fecal scores and the number of detected pathogens showed a significant linear trend (p < 0.001). Of the 7 target pathogens, 6 were detected in samples, but only C. parvum (p = 0.001) and bovine rotavirus (p < 0.001) were found at significantly higher rates in diarrheic calves than in non-diarrheic calves. Only Eimeria spp. showed a significant linear trend between the detection rate of the pathogen and the age groups (p < 0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.1022-1025
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• 2002

Effect of chemical stress of daily administration of glucocorticoid (dexamethasone @0.125 mg./calf/day) injections on plasma zinc levels, Zn status of body tissues and its distribution in sub cellular fractions, was studied in neonatal buffalo calves. Daily i/m injections of dexamethasone, starting at the completion of 1 week of age and continued till 8th week, led to a significant decline in plasma Zn concentration from 3rd week onwards, which then persisted throughout the rest of the experimental period. In control group, liver had the highest concentration of zinc, followed by heart, muscle, spleen, kidney and testis. In all these tissues, cytosolic fractions had the highest (>60%) zinc levels followed by nuclear, mitochondrial and microsomal fractions. In dexamethasone treated calves, there was a significant increase in the Zn uptake by the tissues of liver and muscle. This increase in zinc concentration was observed in all the sub cellular fractions of liver and muscle, however about 80% of this increase was in cytosolic fraction. It was concluded that glucocorticoid-induced stress caused increase in Zn levels of liver/muscles and decrease in blood plasma zinc, thus indicating a redistribution of Zn in body.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.348-352
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• 2003

An investigation was made into the protein profile of colostrum/milk of ten Murrah buffaloes and of their ten buffalo calves during their first week of neonatal life to study the materno-neonatal transfer of immunoglobulins (Ig). Calves were pail fed 3.5 liter of colostrum and/or milk per calf/day exclusively from their dam. First blood sample from newborn calves was collected before colostrum feeding on the day of birth (day zero) and the sampling continued daily for seven days after colostrum/milk feeding. Colostrum/milk Ig and IgG values were $4.82{\pm}2.60$, $2.19{\pm}1.90$, $1.12{\pm}0.82$, $0.69{\pm}0.44$, $0.59{\pm}0.31$, $0.47{\pm}0.20$, $0.40{\pm}0.22$, $0.40{\pm}0.25$ and $3.58{\pm}1.90$, $1.08{\pm}0.92$, $0.52{\pm}0.40$, $0.31{\pm}0.20$, $0.27{\pm}0.14$, $0.22{\pm}0.08$, $0.18{\pm}0.09$, $0.14{\pm}0.08$ respectively during 0-7 days post partum. The concentration of total colostrum/milk proteins, Ig, IgG and albumin were highest within 12 h post-partum. Thereafter, the concentrations followed a declining trend which may be attributed to the reduced transfer of proteins from the maternal blood, declining synthesis by the mammary glands and/or depletion of stored proteins. The concentrations of plasma Ig and IgG before colostrum feeding on day zero were $0.42{\pm}0.09$ and $0.08{\pm}0.03$ respectively. The levels of plasma Ig were $1.90{\pm}0.37$, $1.80{\pm}0.31$, $1.80{\pm}0.26$, $1.81{\pm}0.28$, $1.78{\pm}0.31$, $1.79{\pm}0.21$, $1.80{\pm}0.32$ and of IgG were $1.57{\pm}0.41$, $1.30{\pm}0.29$, $1.31{\pm}0.21$, $1.27{\pm}0.18$, $1.23{\pm}0.21$, $1.23{\pm}0.16$, $1.26{\pm}0.21$ on days 1-7 after birth after colostrum/milk feeding. The concentrations of total plasma proteins, Ig, IgG were lowest before colostrum feeding and increased significantly (p<0.05) after colostrum feeding in buffalo neonates. The results suggest that the highest amounts of colostral Ig and IgG were available on the day of parturition and thus the calves should receive colostrum as early after birth as possible. Colostrum Ig and IgG concentrations were not correlated to plasma Ig and IgG concentrations in the post-suckle buffalo calves and therefore, colostrum Ig and IgG concentrations were probably not the principle determinants of calf post-suckle plasma Ig and IgG concentrations.