This study was performed to investigate immune changes by comparing the proportion and function of immune cells in the blood under high-temperature period and convalescence temperature period in Holstein dairy cows. The experiment was conducted using Holstein dairy cows of five animals per group (60 ± 20 months old, 175 ± 78 non-day) from the National Institute of Animal Science at high-temperature period (THI: 76 ± 1.2) and convalescence temperature period (THI: 66 ± 1.3). Complete blood count results showed no change in the number of immune cells between groups. In the analysis using Flow Cytometry of PBMCs, no significant differences were observed among B cells, Helper T cells, cytotoxic T cells, and γδ T cells between groups. However, there was an increase in Th17 cells producing IL-17a, while Th1 cells decreased during the convalescence temperature period. The results of gene expression analysis using qRT-PCR in PBMCs revealed an increase in IL-10 during the convalescence temperature period, while a decrease in HSP70 and HSP90 was observed. In conclusion, the increased expression of IL-10 and the decrease in HSP expression suggest the possibility of a weak recovery from heat stress. However, the lack of observed changes in B cells, T cells, and other immune cells indicates incomplete recovery from heat stress during the convalescence temperature period.

본 연구의 목적은 우리나라 Jersey 암소 56두로부터 조사된 체고 데이터에 대해 성장 모형을 추정하고, 추정된 체고 성장 모형의 모수를 활용하여 우리나라 Jersey 암소의 체고 성장 기초 자료를 제공하고자 실시하였다. 추정된 Gompertz, von Bertalanffy, Logistic 및 Brody 모형의 체고 성장 곡선 함수식은 각각      ,         ,          및       이었다. 추정된 Gompertz, von Bertalanffy 및 Logistic 모형의 모수를 이용하여 성장 특성을 분석한 결과 변곡점 월령이 각각 -0.3880, -5.235 및 -0.426월로 성장 기간 중 존재하지 않았다. Gompertz, von Bertalanffy, Logistic 및 Brody 모형에 대한 오차 평균 제곱합은 각각 14.189, 14.083, 14.730 및 14.011로 추정되었으며, 모형 결정 계수는 각각 0.971, 0.972, 0.970 및 0.972로 추정되었 다. 각 모형의 오차 평균 제곱합과 모형 결정 계수의 결과를 종합해보면 Brody 모형이 Jersey 암소의 체고 성장 곡선에 적합도가 좋은 것으로 판단된다.

본 연구는 우리나라 Jersey 암소 41두로부터 측정된 체중 데이터를 이용해 Gompertz, von Bertalanffy 및 Logistic 모형의 성장 곡선을 추정하고, 추정된 성장 곡선의 모수를 활용하여 Jersey 암소의 성장 특성에 대해 알아보고자 실시하였다. 추정된 Gompertz, von Bertalanffy 및 Logistic 모형의 성장 곡선 함수식은 각각    ,         및          이었다. Gompertz, von Bertalanffy 및 Logistic 모형에 대해 변곡점은 각각 10.719, 8.4292 및 14.618 개월로 추정되었고, 변곡점 체중은 각각 208.514, 211.347 및 203.548kg으로 추정되었으며, 최대 증체율은 각각 20.851, 21.192 및 21.993 (kg/월)로 추정되었다. 오차 평균 제곱합과 모형 결정 계수의 결과를 종합해보면 von Bertalanffy, Gompertz 그리고 Logistic 모형 순으로 Jersey 암소 성장 곡선에 적합도가 높은 것으로 판단된다.

The objective of the present study was to determine the best model to describe and quantify the changes in live body weight, height at withers, height at rump, body length and chest girth of Holstein cows raised under Korean feeding conditions for 50 months. The five standard growth models namely polynomial linear regression models, regression of growth variables on the first and second-order of ages in days (model 1) and regression of growth variables on age covariates from first to the third-order (model 2) as well as non-linear models were fitted and evaluated for representing growth pattern of Holstein cows raised in Korean feeding circumstances. Nonlinear models fitted were three exponential growth curve models; Brody, Gompertz, and von Bertalanffy functional models. For this purpose, a total of 22 Holstein cows raised in Korea used in the period from April 2016 to May 2020. Each model fitted to monthly growth curve records of dairy cows by using PROC NLIN procedure in SAS program. On the basis of the results, nonlinear models showed the lower root mean square of error (RMSE) for live body weight, height at withers, height at rump, body length and chest girth (12.22, 1.95, 1.55, 4.04, 2.06) with higher correlation coefficiency (R2) values for live body weight, height at withers, height at rump, body length and chest girth (0.99, 0.99, 0.99, 1.00, 1.00). Overall, the evaluation of the different growth models indicated that the Gompertz model used in the study seemed to be the most appropriate one for standard growth of Holstein cows raised under Korean feeding system.

Barley is an important cereal gain which is traditionally used in some nations of Asia and North Africa, and there has been growing interest in using barley as an ingredient in food due to their nutritional value and high content of phyto-constituents. However, no study report on comparative feed value between sprouted barley, cornflake and alfalfa hay. Therefore, in this study we aimed to evaluate the chemical composition, amino acid profile and mineral content of 6 day sprouted barley fodder (SBF) compared with cornflake and alfalfa hay using by AOAC method, as an alternative feed ingredient. Results showed that SBF had higher content of crude protein, acid detergent insoluble crude proteins and neutral detergent insoluble crude protein than alfalfa hay and cornflake; cornflake had higher crude fiber, neutral detergent fiber content than SBF and alfalfa hay; alfalfa hay had higher crude fiber, crude ash, acid detergent fiber, neutral detergent fiber and lignin level than SBF and cornflake. Also, significant differences were found on amino acid content among them (p<0.01). The most abundant amino acid in SBF was glutamate (123 g/kg DM), which is higher than in alfalfa hay (1.27%) or cornflake (1.58%). However, methionine (1.33%) and cysteine (1.53%) were the least abundant amino acids in SBF compared with cornflake or alfalfa hay. Furthermore, our study results exhibited that SBE comprise a good sources of minerals including ferrous (90.01 mg/kg) followed by zinc (20.50 mg/kg), magnesium (0.20 mg/kg) and sodium (0.03 mg/kg) as compared to cornflake and alfalfa hay. The present research findings, confirmed that the nutritional values of SBF are comparable to those of cornflake and alfalfa hay. Hence, SBF can be a better alternative feed ingredient for cornflake or alfalfa hay. However, feeding trials will be required to determine acceptability of SBF for ruminant production.

The present study was designed to determine the effect of barn or cycle of grazing on changes of biochemical metabolites in prepartum and changes of milk composition in postpartum of dairy cows. For this purpose, a total of sixteen 25 months old Holstein primiparous dairy cows were allocated in two groups (n=8) with an average body weight of 571.61 ± 35.30 kg (Barn) and 578.10 ± 39.20 kg (Grazing). The study was conducted from June 2018 to October 2018. Results revealed that barn raised dairy cows had a higher increase in their serum albumin and calcium level on day 14 prepartum. However, the level of palmitic acid, saturated fatty acid increased significantly, and the level of fat, oleic acid, γ-linoleic acid, arachidonic acid and unsaturated fatty acids decreased significantly in barn raised dairy cow’s milk on day 14 postpartum. There were no significant differences observed with respect to all other biochemical metabolites, fatty acids and minerals between barn raised and cycle grazing dairy cows during prepartum and postpartum. Our study results could serve to a better understanding of barn raised cow with respect to changes of biochemical metabolites in prepartum and changes of milk composition, fatty acids and minerals content in grazing dairy cows in postpartum for estimating their physiological status.

An experiment was carried out to assess the effect of feed selenium-lysine (Se-Lys) supplementation on milk compositions and serum biochemical indices in Saanen dairy goats in Korea. A total of twelve 36 months old Saanen lactating dairy goats (47±6.21 kg) fed the similar dry matter intake twice a day at 2% of BW (DMI) (10.9% moisture of concentrate and 19% moisture of roughage), milk yield (2.5 kg/d) and parity (2) were randomly selected and subjected for the present study, divided into two groups with six goats in each group. The goats in the control group received rice hulls (10 g/ day) only, and did not receive Se-Lys; goats in the treatment group were fed 0.06 g of Se-Lys with 10 g of rice hulls every day before feeding roughage for six weeks. The milk sample was collected every week, and its compositions were analyzed. The results of the present study showed that there is no significantly increased milk production in Se-Lys treated group goats when compared with control group goats. But, Se-Lys treatment significantly increased the milk protein content (3.98±0.16%), fat (3.72±0.27%), lactose (4.07±0.14%), total solids (12.51±0.28%) and urea (14.42±1.45 mg/dl) content as compared to the control group goats (p<0.05). The somatic cell counts (207,740±28.81 cells/ml) were significantly lower in the Se-Lys treated group than in the control group (p<0.05). Also, the results of the current study showed that supplementation of Se-Lys were significantly decreased the blood biochemical indices of IL-6 (34.34±6.04 pg/ml), TNT-α (0.56±0.22 ng/ml), MDA (5.07±1.03 ng/ml), GPx-1 (9.07±5.17 ng/ml), sCD4 (2.64±1.02 ng/ml) and sCD8 (5.08±2.08 ng/ml) level when compared with without addition of Se-Lys group dairy goats (p<0.05). On the other hand, the selenoprotein P (1,580.18±127.62 ng/ml) level was significantly higher in Se-Lys supplemented group than in the control group (p<0.05). Based on the study results, it was concluded that feed Se-Lys supplementation may improve milk yield with positively improved protein, fat, lactose, total solids, urea content, and biochemical indices without negative effects on milk production traits.

Although some factors, including season, age, type of estrus (natural estrus vs. induced estrus) and semen type (conventional vs. sexed), affect the conception rate following artificial insemination (AI) in dairy cattle, there is little information about the influence of ovarian characteristics, such as preovulatory follicle (PF) location at estrus, on fertility in dairy cattle. In most breeds of cattle the right ovary appears to function more actively than the left and about sixty percent of pregnancies in dairy cattle occur in the right horn of uterus (Reece and Tuner, 1938). Our study aimed to compare conception rates in dairy cattle between PFs that developed in the left ovary and those that developed in the right ovary at estrus. In this study, we examined the locational effect (left or right ovary) of the preovulatory follicle (PF) on fertility in dairy cattle. In total, 955 artificial inseminations (AI) were analyzed. At AI, PF locations were examined using rectal palpation, and dairy cattle were divided into two groups on their PF locations: (i) the PF located in the left ovary (L-PF); and (ii) the PF located in the right ovary (R-PF). Pregnancy was diagnosed by rectal palpation or ultrasonographic examination 60 days after AI. The conception rate was 38.1% in all dairy cattle. Conception rate was higher in the R-PF (40.8%) than in the L-PF (33.2%). In summary, PF development in the right ovary was associated with increased conception rates in dairy cattle.

A diverse of recommendation has been made for the structure and management of dairy cows, despite demanding research, the relationship between lactation number and various factors is yet to be established. The present study was aimed to investigate the covariance among lactation number, growth performance, calving interval, and milk production was considered to increase an efficiency of selection schemes and to manage more efficiently Holstein dairy cows that have been raised on small-scale family farms in Republic of Korea. For that purpose, the data were observed from 850 Holstein dairy cows, which a total of 3929 milking, since April 2016 - January 2017. We measured the body weight, height, age, calving interval, and milk production of the each dairy cow. Also, information about the date of lactation, calving interval, and milk production was recorded using an automatic milking system(AMS) with identification numbers. Milk production was calculated per udder quarter in the AMS. Our study results showed the increased average body weight(p>0.05) in 1, 2, 3, and 4th lactating dairy cows and afterwards, we noticed the tendency on the average body weight(p<0.05) per lactation progressed. There was no significant difference noticed on height measurement of dairy cows. From the processing data of 850 Holstein dairy cows, the lactation number 1 and 7 had a greater calving interval with significantly lowered milk production, and the lactation number 2, 3, 4, 5, and 6 had significantly lowered the calving interval(p<0.05) with a greater milk production. From our study results, we evidenced that there is a significant relationship between the lactation number, growth performance, calving interval, and milk yield, and the maximum production of milk occurring in the 3rd and 4th lactation dairy cows. The achieved results from this study can be used by the small-scale farmers to encourage the structure and management of growth performance, calving interval, and milk yield in Holstein dairy cows in Korea.

본 시험은 포도부산물의 첨가가 젖소의 산유량, 유성분 및 혈액 성상에 미치는 영향을 조사하기 위하여 실시하였다. 비유중기 젖소 8두(평균 월령: 89.8, 평균 유기: 164.4, 평균 산차: 2.8산)를 공시하였으며, 포도부산물을 첨가하지 않은 대조구와 1일 1 kg을 첨가한 시험구로 두 처리구를 설정하여 3주간 급여하였다. 유지방, 유단백, 유당 및 총 고형물 함량은 처리간에 차이가 없었다. 그러나 산유량은 포도부산물 을 첨가한 처리구가 23.13 kg/d으로 대조구의 21.16 kg/d에 비해 높은 반면(p<0.05), 체세포 수는 대조구가 포도부산물 처리구에 비해 높았다(p<0.05). 혈중 glucose, alanine aminotransferase, total protein 및 blood urea nitrogen 함량은 처리구간 차이가 없었으나, AST와 총콜레스테롤 함량은 대조구 (123.75 IU/L, 200.82 mg/dl)가 포도부산물 처리구(95.34 IU/L, 180.63 mg/dl)에 비해 높았다(p<0.05). 이상의 결과에서, 다양한 생리활성을 가진 포도부산물은 젖소를 위한 기능성 사료로 이용 가능성이 높을 것으로 사료된다.