Journal of Animal Science and Technology最新文献

Focusing high marble deposition, Hanwoo feedlot system uses high-energy diet over the prolonged fattening period. However, due to the individual genetic variation, around 40% of them are graded into inferior quality grades (QG), despite they utilized the same resources. Therefore, focusing on development of a nutrigenomic based precision management model, this study was to evaluated the response to the divergent selection on genetic merit for marbling score (MS), under different dietary total digestible nutrient (TDN) levels. Total of 111 calves were genotyped and initially grouped according to estimated breeding value (high and low) for marbling score (MS-EBV). Subsequently, managed under two levels of feed TDN%, over the calf period, early, middle, and final fattening periods following 2 × 2 factorial arrangement. Carcasses were evaluated for MS, Back fat thickness (BFT) and Korean beef quality grading standard. As the direct response to the selection was significant, the results confirmed the importance of initial genetic grouping of Hanwoo steers for MS-EBV. However, dietary TDN level did not show an effect (p > 0.05) on the MS. Furthermore, no genetic-by-nutrition interaction for MS (p > 0.05) was also observed. The present results showed no correlation response on BFT (p > 0.05), which indicates that the selection based on MS-EBV can be used to enhance the MS without undesirable effect on BFT. Ultimate turnover of the Hanwoo feedlot operation is primarily determined by the QGs. The present model shows that the initial grouping for MS-EBV increased the proportion of carcasses graded for higher QGs (QG1⁺⁺ and QG1⁺) by approximately 20%. Moreover, there appear to be a potential to increase the proportion of QG 1⁺⁺ animals among the high-genetic group by further increasing the dietary energy content. Overall, this precision management strategy suggests the importance of adopting an MS based initial genetic grouping system for Hanwoo steers with a subsequent divergent management based on dietary energy level.

The objective of this study was to quantitatively estimate the level of grazing area damage in outdoor free-range pig production using a Unmanned Aerial Vehicles (UAV) with an RGB image sensor. Ten corn field images were captured by a UAV over approximately two weeks, during which gestating sows were allowed to graze freely on the corn field measuring 100 × 50 m². The images were corrected to a bird's-eye view, and then divided into 32 segments and sequentially inputted into the YOLOv4 detector to detect the corn images according to their condition. The 43 raw training images selected randomly out of 320 segmented images were flipped to create 86 images, and then these images were further augmented by rotating them in 5-degree increments to create a total of 6,192 images. The increased 6,192 images are further augmented by applying three random color transformations to each image, resulting in 24,768 datasets. The occupancy rate of corn in the field was estimated efficiently using You Only Look Once (YOLO). As of the first day of observation (day 2), it was evident that almost all the corn had disappeared by the ninth day. When grazing 20 sows in a 50 × 100 m² cornfield (250 m²/sow), it appears that the animals should be rotated to other grazing areas to protect the cover crop after at least five days. In agricultural technology, most of the research using machine and deep learning is related to the detection of fruits and pests, and research on other application fields is needed. In addition, large-scale image data collected by experts in the field are required as training data to apply deep learning. If the data required for deep learning is insufficient, a large number of data augmentation is required.

In this study, rumen temperature and environment in estral and non-estral Korean Native breeding cattle were evaluated by using a bolus sensor. Behavioral and physiological changes in study animals were also assessed. To assess the rumen temperature and environment, we inserted bolus sensors into 12 Korean Native cattle with an average age of 35.5 months, then measured temperature and activity within the rumen using the wireless bolus sensor. Drinking, feeding and mounting behavior, and measured vaginal temperature and levels of intravaginal mucus resistance were recorded. We found that cattle in estrus exhibited more acts of mounting (37.4 vs. 0 times/day), increased vaginal temperature (39.0°C vs. 38.4°C), and decreased vaginal mucus resistance (136.3 Ω vs 197.4 Ω), compared with non-estral animals. Furthermore, increased levels of rumen activity were most significant in estrus cattle at the highest activity levels (p < 0.01). Overall, the estrus group exhibited increased rumen temperature (p = 0.01), compared with the non-estrus group. In conclusion, the results of this study not only provide basic physiological data related to estrus in improved Korean Native breeding cattle, but also suggest that monitoring of rumen temperature and activity might be used as an effective smart device for estrus detection.

Rumination in cattle is closely related to their health, which makes the automatic monitoring of rumination an important part of smart pasture operations. However, manual monitoring of cattle rumination is laborious and wearable sensors are often harmful to animals. Thus, we propose a computer vision-based method to automatically identify multi-object cattle rumination, and to calculate the rumination time and number of chews for each cow. The heads of the cattle in the video were initially tracked with a multi-object tracking algorithm, which combined the You Only Look Once (YOLO) algorithm with the kernelized correlation filter (KCF). Images of the head of each cow were saved at a fixed size, and numbered. Then, a rumination recognition algorithm was constructed with parameters obtained using the frame difference method, and rumination time and number of chews were calculated. The rumination recognition algorithm was used to analyze the head image of each cow to automatically detect multi-object cattle rumination. To verify the feasibility of this method, the algorithm was tested on multi-object cattle rumination videos, and the results were compared with the results produced by human observation. The experimental results showed that the average error in rumination time was 5.902% and the average error in the number of chews was 8.126%. The rumination identification and calculation of rumination information only need to be performed by computers automatically with no manual intervention. It could provide a new contactless rumination identification method for multi-cattle, which provided technical support for smart pasture.

Escherichia coli (E. coli) and Salmonella enterica (SE) infections in pigs are major source associated with enteric disease such as post weaning diarrhea. The aim of this study was to investigate the effects of Pediococcus pentosaceus in weaned piglets challenged with pathogen bacteria. In Experiment.1 90 weaned piglets with initial body weights of 8.53 ± 0.34 kg were assigned to 15 treatments for 2 weeks. The experiments were conducted two trials in a 2 × 5 factorial arrangement of treatments consisting of two levels of challenge (challenge and non-challenge) with E. coli and SE, respectively and five levels of probiotics (Control, Lactobacillus plantarum [LA], Pediococcus pentosaceus SMFM2016-WK1 [38W], Pediococcus acidilactici K [PK], Lactobacillus reuteri PF30 [PF30]). In Experiment.2 a total of 30 weaned pigs (initial body weight of 9.84 ± 0.85 kg) were used in 4 weeks experiment. Pigs were allocated to 5 groups in a randomized complete way with 2 pens per group and 3 pigs per pen. Supplementation of LA and 38W improved (p < 0.05) growth performance, intestinal pathogen bacteria count, fecal noxious odor and diarrhea incidence. In conclusion, supplementation of 38W strains isolated from white kimchi can act as probiotics by inhibiting E. coli and SE.

The effect of different commercially available bedding materials on the growth performance and carcass characteristics of ducks for 42 days was investigated. 336 one-day-old White-Pekin ducklings (60.48 ± 0.16 g) were randomly allocated into 24-floor pens with one of the three beddings namely i) coco peat, ii) rice husks, or iii) sawdust. 14 ducklings per pen and 8 replicate pens per bedding material were used. Birds were fed a starter diet from days 1-21 and a grower diet from days 22-42. Weekly growth performance evaluation was conducted for the average body weight, weight gains, daily feed intake, and feed conversion efficiency. One bird per pen was sacrificed on day 42 for the evaluation of carcass characteristics including the carcass, breast, and leg muscle percentages. Breast and leg muscle samples were then collected and analyzed for their proximate and pH values. Higher body weights (p < 0.05) were noticed with rice husks on day 42 only. Improved daily gains (p < 0.05) were also noticed for birds raised with rice husks over the entire period (days 1-42). Concerning feed intake, higher values (p < 0.05) were similarly noted with rice husks for the grower phase (days 22-42), and the entire experimental period (days 1-42). Marginally improved feed intake values were also noted with the use of rice husks as the bedding materials on day 42 (p = 0.092). Improved feed efficiency (p < 0.05) was noticed with rice husks on day 35, the grower period, and the entire 42-day period. However, no significant differences were noticed for most of the carcass characteristics that were evaluated. Nevertheless, higher (p < 0.05) pH values for the breast muscle were noticed with the use of coco peat and sawdust as the bedding. Conclusively, the bedding type could have a significant impact on the growth performance of ducks without adverse effects on carcass characteristics. The use of rice husks as bedding might be advantageous and is therefore recommended.

Korea is currently developing country-specific emission factors to support the 2050 zero-carbon campaign. Dairy cattle represent one of the largest livestock industries in Korea, and the industry is estimated to continue increasing because of an increase in milk demand. However, country-specific emission factors for dairy cattle are currently only available for calculating methane (CH₄) emissions from enteric fermentation. Two experiments were conducted to evaluate CH₄ and nitrous oxide (N₂O) fluxes from sawdust-bedded barn in dairy cow and steer, as well as dairy cattle manure composting lots. The greenhouse gas (GHG) fluxes were quantified using the open-chamber method and gas chromatography. CH₄ fluxes from steer, dairy cow, and manure compost were 27.88 ± 5.84, 36.12 ± 10.85, and 259.44 ± 61.78 µg/head/s, respectively. N₂O fluxes from steer, dairy cow, and manure compost were 14.04 ± 1.27, 4.11 ± 1.57, and 3.97 ± 1.08 µg/head/s, respectively. The result of this study can be used to construct country-specific data for GHG emissions from manure management. Thus, the application of mitigation strategies can be prioritized based on the GHG profile and targeted source.

Lactobacillus amylovorus CACC736 was originated from swine feces in Korea. The complete genome sequences of the strain contained one circular chromosome (2,057,809 base pair [bp]) with 38.2% guanine-cytosine (GC) content and two circular plasmids, namely, pCACC736-1 and pCACC736-2. The predicted protein-coding genes, which are encoding the clustered regularly interspaced short palindromic repeats (CRISPR)-associated proteins, biosynthesis of bacteriocin (helveticin J), and the related proteins of the bile, acid tolerance. Notably, the genes related to vitamin B-group biosynthesis (riboflavin and cobalamin) were also found in L. amylovorus CACC736. Collectively, the complete genome sequence of the L. amylovorus CACC736 will aid in the development of functional probiotics in the animal industry.

The current study evaluated carbon dioxide (CO₂) emissions from beef and pork production and distribution chains in the South Korean meat industry. Data from industrial example farms and slaughterhouses were assessed on the basis of both the guidelines from the United Kingdom's Publicly Available Specification (PAS) 2050:2011 and the Korea Environmental Industry & Technology Institute carbon footprint calculation. The main factors for our estimations were animal feeds, manure waste, transportation, energy and water, refrigerants, and package data. Our analyses show that 16.55 kg CO₂ equivalent (eq) was emitted during the production of 1 kg of live cattle. When retail yields and packing processes were considered, the CO₂-eq of 1 kg of packaged Hanwoo beef was 27.86 kg. As for pigs, emissions from 1 kg of live pigs and packaged pork meat were 2.62 and 12.75 kg CO₂-eq, respectively. While we gathered data from only two farms and slaughterhouses and our findings can therefore not be extrapolated to all meats produced in the South Korean meat industry, they indicate that manure waste is the greatest factor affecting ultimate CO₂ emissions of packaged meats.

Protein-translated mRNA analysis has been extensively used to determine the function of various traits in animals. The non-coding RNA (ncRNA), which was known to be non-functional because it was not encoded as a protein, was re-examined as it was studied to actually function. One of the ncRNAs, long non-coding RNA (lncRNA), is known to have a function of regulating mRNA expression, and its importance is emerging. Therefore, lncRNAs are currently being used to understand the traits of various animals as well as human diseases. However, studies on lncRNA annotation and its functions are still lacking in most animals except humans and mice. lncRNAs have unique characteristics of lncRNAs and interact with mRNA through various mechanisms. In order to make lncRNA annotations in animals in the future, it is essential to understand the characteristics of lncRNAs and the mechanisms by which lncRNAs function. In addition, this will allow lncRNAs to be used for a wider variety of traits in a wider range of animals, and it is expected that integrated analysis using other biological information will be possible.