• 한국임상수의학회지
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• 제20권1호
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• pp.121-130
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• 2003

The purpose of this study was to investigate the effect of breeding conditions on reproductive efficiency of thoroughbred broodmares by ultrasonography. The mean age and breeding career of 120 mares used in this study were 11 years old and 6 years, respectively. The average pregnancy rate and embryonic loss rate were 87.5%, 11.8%. The groups that were 8-10 years old, 4-6 years, maiden and mated on May showed the highest pregnancy rate. While mares mated on 1st estrus post partus had the highest ovulation rate but showed the highest embryonic loss rate and he lowest pregnancy rate. And broodmares that had more intrauterine foreign bodies such as cyst and fluid with age and breeding career had represented lower pregnancy rate and higher embryonic loss rate than those having normal uterine condition. These results suggest that the breeding condition and uterine environment of mares had a significant influence on reproductive efficiency.

• 한국임상수의학회지
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• 제21권2호
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• pp.115-121
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• 2004

The purpose of this study was to ascertain the breeding efficiency in Thoroughbred mare. A total of 106 mares were investigated for the status of follicle (462 cases), ovulation (179 cases) and pregnancy (346 cases). Of total examination, 46.8% was follicle measure to determine breeding time, and mating rate per cases examined was 39.9%. There was no correlation between reproductive results and size of follicles or endometrial edema or degrees of teasing alone. 143 cases were ovulated among 179 cases which were performed ovulation examination, and ovulation rate and fertilization rate per mating times were 79.9% and 39.0%, respectively. The use of hCG(human chorionic gonadotropin), to facilitate ovulation, presented to increase occurrence of double ovulations and twin fertilizations In conclusion, though more examination to estimate the optimal breeding time and higher mating rate was performed, fertilization rate per mating times was lower and then reproductive efficiency also became decreased. Therefore, it seemed that accurate examination of reproductive tracks, appropriate teasing programme and hCG administration before ovulation were of help to improve ovulation rate and fertilization rate.

• 한국환경과학회지
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• 제28권8호
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• pp.645-654
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• 2019

This study was conducted in two breeding seasons in 2017 to identify nesting habits and breeding biology of barn swallows in Daejang-dong village, Bucheon city, suburban Seoul. Among the 77 barn swallow nests studied, there were 34 breeding nests -27 in the first and 12 in the second. The reuse rate of old nests was 51.6%. In addition to tile-roofed houses (20.6%), breeding nests were most common in brick houses (38.2%) and in slate-roofed houses (26.5%). Most breeding nests were in eaves (58.8%) and front doors (32.3%). The average clutch size was $4.8{\pm}0.9$ in the first and $4.3{\pm}0.5$ in the second. The breeding success rate was 75.0% in the first and 58.1% in the second, considering the hatching rate and the fledgling rate. It was found that the rainy season was affected by a lack of food. At least 27 pairs of nestling barn swallows and 127 young barn swallows successfully fledged were estimated to be 181. These results show that Daejang-dong village is an important suburban habitat of the Seoul metropolitan area, and that it can be used to verify the environmental conservation value of rice fields of in the Seoul metropolitan area.

• 한국동물위생학회지
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• 제46권3호
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• pp.203-210
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• 2023

Breeding ducks are susceptible to fungal infections due to being bred in confined spaces for long periods. The objective of this study was to show the real state of the clinical fungal contamination of 22 duck breeding farms in Chungcheongbuk-do, South Korea. Out of the 430 carcasses obtained from the 22 duck breeding farms, 80 were diagnosed with invasive pulmonary aspergillosis (IPA). Aspergillus spp. were detected as the causative agents, including 26 cases of A. fumigatus, 35 cases of A. flavus, and 19 cases of A. terreus. The clinical lesions in the breeding ducks had circumscribed cream-and-yellow-colored plaques and/or white-to-greenish mycelium. Septate hyphae with parallel walls and dichotomous branching were observed in the histopathological lesions. AGMAg ELISA was performed to determine the overall positive rate of Aspergillus spp. in duck breeding farms. These results showed a positive rate of 58.97% for Aspergillus spp. Additionally, the positive rate increased with the age of the host.

• Asian-Australasian Journal of Animal Sciences
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• 제28권7호
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• pp.943-950
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• 2015

Heat stress has adverse effects on fertility of dairy animals. Decline in fertility is linearly associated with an increase in combination of both temperature and humidity. The purpose of this study was to investigate the relationship between temperature humidity index (THI) and the pregnancy rate of Murrah buffaloes in a subtropical climate. The effects of genetic and non-genetic factors viz., sire, parity, period of calving and age group at first calving were found non-significant on pregnancy rate. The effect of THI was found significant (p<0.001) on pregnancy rate of Murrah buffaloes calved for first time and overall pregnancy rate. The threshold THI affecting the pregnancy rate was identified as THI 75. The months from October to March showed THI<75 and considered as non heat stress zone (NHSZ), while months from April to September were determined as heat stress zone (HSZ) with $THI{\geq}75$. The lowest overall pregnancy rate (0.25) was obtained in July with THI 80.9, while the highest overall pregnancy rate (0.59) was found in November with THI 66.1. May and June were identified as critical heat stress zone (CHSZ) within the HSZ with maximum decline (-7%) in pregnancy rate with per unit increase in THI. The highest overall pregnancy rate was estimated as 0.45 in NHSZ with THI value 56.7 to 73.2. The pregnancy rate was found to have declined to 0.28 in HSZ with THI 73.5 to 83.7. However, the lowest pregnancy rate was estimated as 0.27 in CHSZ with THI value 80.3 to 81.6.

• 한국동물위생학회지
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• 제20권1호
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• pp.95-102
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• 1997

Author investigated internal parasitism for the feces of dog's training center, breeding-dog farm, dairy farm, home by 120 indoor breeding dog and 566 outdoor one in Inchon area. This survey was done from February in 1994 to December in 1995. 1. As a result of total 686 samples, positives were 373(54.4%). Among them, indoor and outdoor breeding dogs were 21(3.1%) 352(51.3%), respectively. 2. According to breeding, it was manifested that 21samples (17.5%) of 120 indoor breeding dogs were positive, and 352 samples(62.2%) of outdoor breeding were positive. 3. The infection rate of dogs for food in dairy farm, breeding dogs in the farm, dog of training center and dog of house is high in order. 4. Infection rate of parasites in 24 dogs breeds, Mongrel dogs were 81.3%, Shepherds were 80.0%, Tosas were 78.4%, Akida and Siberian huskys were 76.2%, Jindos were 55.5%, Pointers were 50.0%, although Afghan hound, Spanial, Shin-tzu, Maltis and Buldog were examined as aparasites negative. 5. After administration with vermicide parasites infection rate were 43.0% in two months. In four months, it were 66.7%, and dogs without vermicide were 87.0%. It seemed like that further research about dosage of vermicide is needed. 6. The rate of single-infection was 37.6% and that of mixed-infection was 16.8%. Among classified 13 types, Ancylostoma caninum 35.6%, Toxocara cams 11.2%, Isospora sp 9.3%, Toxascaris leonina 5.1%, Trychuris vulpis 4.4% were investigated.

• 농업과학연구
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• 제47권4호
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• pp.867-884
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• 2020

Trypoxylus dichotomus is highly utilized in the domestic insect industry and bred at many farms nationwide. Recently, the number of farmers has been increasing due to the expansion of its use in food and medicine. However, the traditional breeding methods have high economic costs, which include relatively large breeding boxes, large amounts of sawdust and a 2 to 1 ratio (or higher) of female to male. Thus, it is essential to develop a cost-effective breeding method. In this study, a breeding cage with a partition was designed and used to investigate the reproduction rate of T. dichotomus with only a single pair of male and female insect. According to the investigation, the average number of eggs laid in the un-partitioned breeding cage was 93.6, and 121.3 eggs were laid in the partitioned breeding cage. This result shows that T. dichotomus lays more eggs in the partitioned breeding cage rather than in the un-partitioned breeding cage. In addition, it was found that T. dichotomus tends to lay more eggs in compressed sawdust, which was harder than the common fermented sawdust. Through a wind-tunnel assay, it was shown that the ovipositing female recognizes the eggs and avoids them to disperse their eggs elsewhere. These results indicate that the partitioned breeding cage may increase the hardness of the sawdust, restrict the adult's movement and provide a new place for oviposition for the female, and therefore results in an increased reproduction rate with less cost.

• Animal Bioscience
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• 제34권12호
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• pp.1879-1885
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• 2021

Objective: Owing to the lack of a breeding index for efficient and quick fertility evaluations of Holstein bulls when using traditional or genome-wide detection methods, this study aimed to determine whether in vitro fertilization (IVF) could be used as an indicator of conception rate of artificial insemination (AI). Methods: Conventional and sexed frozen semen from nine bulls were used for IVF and AI. Results: The IVF and AI conception rates of each bull were confirmed to be positively correlated between the conventional frozen and sexed frozen semen. The correlation coefficient R values of nine bulls between IVF and AI methods were 0.73 and 0.97 for the conventional frozen and sexed frozen semen, respectively. The average conception rate of three bulls undergoing AI was 69.5% and 64.2%, 61.8% and 58.8%, and 48.2% and 46.2% in first-, second-, and third-born cows when conventional frozen and sexed frozen semen were used, respectively, which showed a positive correlation with the fertilization rate in the same parity. We propose an evaluation standard to assess the fertilization ability of bulls based on their IVF test results, which is categorized into three grades: grade one, normal fertility bull with an AI conception rate of 40%±5% and IVF rate of 45% to 60%; grade two, higher fertility bull with an AI conception rate of 50%±5% and IVF rate of 61% to 80%; and grade three, highest fertility bull with an AI conception rate of 60%±5% and IVF rate of >80%. Conclusion: These findings reveal that IVF results can be used as a breeding index for bulls to evaluate their AI conception ability, which may shorten the time required to select bulls for breeding.

• 대한수의학회지
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• 제30권3호
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• pp.349-354
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• 1990

The effects of $PGF2{\alpha}$ on the conception rate and the plasma levels of estradiol-$17{\beta}$ and progesterone of anestrus Cheju mares were investigated at the breeding and non-breeding seasons. The results obtained from this studies are as follows; 1. The durations of the estrus and diestrus after $PGF_2{\alpha}$ treatment persisted shorter than control cycle (p<0.05), but ovulation time was fast. 2. The levels of estradiol-$17{\beta}$ and progesteron before $PGF_2{\alpha}$ treatment showed 103.8pg/ml, 8.0ng/ml in breeding season and 72.8pg/ml, 4.7ng/ml in non-breeding season, respectively. 3. The levels of estradiol-$17{\beta}$ rose to 115.4~154.0pg/ml, and 90.8~27.0pg/ml from 2nd to 6th day after the treatment of $PGF_2{\alpha}$, in breeding and non-breeding seasons, respectively, while progesterone level dropped to 1ng/ml with the sign of estrus and at 8th day rose in breeding season (p<0.05). 4. Of thirty anestrus mares investigated for $PGF_2{\alpha}$ administration, 87.5% showed estrus on an average of 3.8 days after treatment and the conception rate was 62.5% in breeding season, but the estrus and conception rates dropped 40% and 20% in non-breeding season, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제9권4호
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• pp.363-370
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• 1996

The effect of breeding length of sire on genetic progress was examined in the Holstein dairy cattle population in Japan. Genetic progress was extimated by gene flow method. Breeding length of sires directly influences the replacement rates of sires and the selection intensity of sires because there are a fixed number of progeny tested young bulls per year. As breeding length of sires increased, rate of gene flow decreased and average proportions of genes deriving from selected animals had lower asymptotic values. When breeding length was short, average proportions of genes required a longer period to converge to asymptotic values. Changes of Rcow-sire's(sire to breed recorded cows) and Ncow-sire's(sire to breed non recorded cows) breeding length influenced not only transmission of their genes but also that of genes derived from all other selected animals. Irrespective of whether the discount rate was assumed to be 0 or 6%, longer term (${\geq}$ 20 years) expected total genetic improvement was maximized by a sire breeding length of five years. For shorter term assessment(10 years), genetic improvement was maximized by a sire breeding length of three years. There was a linear increase in the contribution of the sire to bulls pathway to the total genetic improvement, with increase in the term of assessment.