This study investigated the effects of silage additives on rumen fermentation characteristics of rye silage. Rye was harvested at ripening stage and treated with different additives in quadruplicate following: without additive (control), with either lactic acid bacteria inoculant (LAB), formic acid (FA), or Ca-formate (Ca-FA). Overall, ensiling characteristics of FA and Ca-FA silages contained 4-fold more (P<0.05) butyrate and 2-fold more (P<0.05) NH3-N concentration (% total nitrogen) than those of control and LAB silages. Cows fed LAB silage showed a diurnal trend with the highest values of propionate concentration compared to the control at 1, 2 and 3 hr after feeding. In contrast, FA and Ca-FA silages increased the proportion of butyrate significantly (P<0.05) at all sampling times compared to control and LAB silage. In conclusion, Forage rye treated with FA or Ca-FA showed different fermentation characteristics during ensilage and in the rumen compared to LAB silage. Further studies are needed to evaluate whether different fermentation characteristics in the rumen between LAB and FA silages had effect on partitioning of nutrients between milk production and body tissue.

This study was to evaluate the feed value of whole crop rice silage (WCRS) and to investigate a suitable ratio of the WCRS and concentrate by an analysis of rumen fermentation. A total of 6 treatments were used according to WCRS: concentrate ratio on in vitro rumen fermentation: T1 (100:0), T2 (60:40), T3 (40:60), T4 (20:80), T5 (10:90), and T6 (0:100). The ruminal pH, total gas emission, ammonia nitrogen, and volatile fatty acid (VFA) were determined as fermentation parameters. Total nutrients digestibility trial was conducted by 4 treatments according to WCRS: concentrate ratio at 40:60 (W40), 20:80 (W20), and 10:90 (W10), respectively. Feed value was analyzed according to AOAC (2019) and nutrient digestibility was calculated based on NRC (2001). The levels of crude protein (CP), crude fat, and neutral detergent fiber of the WCRS were 12.29%, 1.67%, and 59.79%, respectively. It was found to be 51.49% as a result of predicting the total digestible nutrient of WCRS using the NRC (2001) model. In vitro rumen fermentation, T4, T5, and T6 treatments showed a greater gas emission and total VFA concentration compared with other treatments (p<0.05). Acetate and acetate to propionate ratio of T4, T5, and T6 were significantly higher than other treatments (p<0.05). There was a significant difference in the level of propionate and butyrate according to the WCRS: concentrate ratio (p<0.05). The digestibility of dry matter and CP was significantly lower in W40 than in other treatments (p<0.05); however, there was no difference in W20 and W10. In conclusion, the 20:80 (WCRS: concentrate) is beneficial for stabilizing the rumen that does not inhibit rumen fermentation and nutrient digestion. This ratio might have a positive effect on the economics of farms as a valuable feed.

An intensive analysis was conducted of the maternal lineages of the Jeju native pigs (JNPs). A total of 100 mtDNA sequences from Asian wild boars (AWB), European wild boars (EWB), Asian domestic pigs (ADP), European domestic pigs (EDP), and JNPs were used for the phylogeny and network analyses. Two distinct JNP groups were found JNPA and JNPE in the Asian and European cluster. The maternal lineage of JNPE was the closest to that of EWB and a clear haplogroup sharing an identical haplotype (hap16) among 15 individuals of JNPE and 2 individuals of EWB was identified. However, except for hap18, no EDP shared any identical haplotypes with JNPE, suggesting that no obvious maternal contribution of EDP has occurred in JNPE in recent years. The possible existence of an additional and unknown path of maternal lineage from EDP into JNPE could therefore be postulated, in addition to those from AWB and ADP into the JNPA groups. Thus, JNPE appeared to have a pure maternal lineage that had no recent contact with EDP, and both the JNPA groups and JNPE are pure Jeju native pigs.

Alterations affecting the status of robustness and health can bring about physiological changes including hematological parameters in pigs. To identify quantitative trait loci (QTL) associated with 8 hematological phenotypes (one leukocyte trait, six erythrocyte traits, and one platelet trait), we performed a genome-wide association study using the Porcine SNP 60K BeadChip in an intercross population between Landrace and Korean native pigs. A total of 36,740 SNPs from 816 F2 offspring were analysed for each blood related traits after filtering by quality control. Data were analysed genome-wide rapid association using the mixed model and regression (GRAMMAR) approach. A total of 257 significant SNPs (P<1.36x10-6) on SSC3, 6, 8, 13, and 17 were detected for blood related traits in this study. Interestingly, the genomic region between 17.9 and 130 Mb on SSC8 was found to be significantly associated with RBC, MCV, and MCH. Our results include 5 significant SNPs within five candidate genes (KIT, IL15, TXK, ARAP2, and ERG) for hematopoiesis. Further validation of these identified SNPs could give valuable information for understanding the variation of hematological traits in swine.

Previously, we reported a quantitative trait locus (QTL) that affect total teat number (TTN) on pig chromosome 7 (SSC7) in a large F2 intercross population between Landrace and Korean native pigs. The aim of this study was to refine the QTL associated with TTN and to identify positional candidate gene(s) within the refined genomic region. TTN was recorded in 1,105 F2 progeny. All experimental animals were genotyped using 998 informative single nucleotide polymorphism (SNP) markers located on SSC7. A haplotype-based linkage and association analysis using the PHASEBOOK programme was applied to perform high-resolution QTL analysis. Additionally, linear mixed-effect models were used to assess the effect of a positional candidate gene on TTN and other economically important traits [i.e., thoracic vertebrae number (THO), carcass body length (CBL) and weight (CW), back fat thickness (BFT) and intramuscular fat content (IMF) in loin muscles]. Joint linkage and association analysis refined the critical region to a 1.07 Mb region that included a novel positional candidate gene, BRMS1L, that encodes the breast cancer metastasis-suppressor 1-like protein, which could possibly be implicated in normal mammary gland development. Significant association of an SNP marker (g.-1087 G>A) in the 5’-flanking region of BRMS1L with TTN (P=1.10x10-8), THO (P=5.80x10-4), and CBL (P=0.038) was observed. Based on these data, we propose BRMS1L as a positional candidate gene for TTN in pigs. After validation of the association in other independent populations and further functional studies, these results could be useful in optimizing breeding programmes that improve TTN and other economically important traits in swine

본 연구는 농후사료의 급여수준을 달리하여 제주산마 에게 급여하는 경우에 체중 변화, 장내 미생물 조성 및 혈액성상의 변화에 미치는 효과를 구명하기 위하여 수행 되었다. 공시축으로 24-36개월의 제주산마(제주마×더러브 렛) 14두를 공시하였으며, 농후사료의 급여수준을 체중의 1.5%(5두), 2%(4두)와 2.5%(5두)로 급여하여 봄과 겨울 증 체율 및 혈액 특성과 생리적 변화를 조사하였다. 봄에 총 증체량은 1.5%, 2%, 2.5% 급여한 처리구에서 12.6kg, 21.5kg, 29.0kg, 겨울에 총 증체량은 21.6kg, 28.0kg, 42.6kg을 나타냈고, 일당 증체량은 봄에는 0.23kg, 0.39kg, 0.54kg, 겨울에는 0.40kg, 0.52kg, 0.79kg을 나타내어 체중의 2.5%를 섭취한 구에서 높은 경향을 나타내었다. 내독 소는 농후사료 과다 섭취에 의해 그람음성균의 세포벽에 서 방출되는 물질로 봄에 시행한 시험에서 3주차 때 농 후사료를 체중의 2%와 2.5%를 급여한 처리구에서 유의 적으로 낮은 결과를 나타내었으나(p<0.05) 이후에는 점차 모든 처리구에서 수치가 비슷해져 적응하는 경향을 보여 모든 처리구가 농후사료 급여에 적응하는 경향을 보였다. 봄에 실시한 실험에서 8주차에 분 pH는 농후사료를 체 중의 1.5%, 2%, 2.5% 급여한 처리구에서 각각 6.2, 5.8, 5.7로 나타나 농후사료를 체중의 2%와 2.5%를 급여한 처 리구에서 유의적으로 낮은 결과를 나타내었다(p<0.05). 직장온도는 겨울에 실시한 실험에서 8주차에 농후사료를 1.5%, 2%, 2.5%. 급여구에서 각각 37.8℃, 37.9℃, 38.4℃ 를 나타내어 농후사료 2.5% 급여구에서 직장온도가 유의 적으로 높은 수치를 나타내었다(p<0.05). 분내 미생물에 서는 셀룰로오스와 탄수화물(구조 탄수화물) 분해에 관여 하는 미생물로 알려진 Fibrobacter가 체중의 1.5% 급여했 을 경우 총 미생물군에서 2.49%를 차지하였고, 2%와 2.5% 급여구에서는 각각 1.42%와 1.09%를 차지하여 농후 사료 급여량이 증가할수록 유의적으로 감소하는 경향을 보였다. 결론적으로 농후사료 2.5%의 급여가 비육마 사육 방법으로 활용할 수 있을 것으로 사료된다.

The objective of this study was to determine the growth characteristics of cool (C1) and warm season grasses (C2) in pastures mixed with C1 and C2 suitable for grazing horses and effect of pastures mixed with tall and short grasses on the intake characteristics of horses. C1 used in this study was Kentucky bluegrass, Redtop (short type grass) and tall type grasses were orchardgrass and tall fescue, respectively. The short type grass used as C2 was Bermudagrass. This study had the following four treatment groups: 1) Treatment 1 (Bermudagrass + Kentucky bluegrass + Redtop) 2) Treatment 2 (Bermudagrass + tall fescue + orchardgrass) 3) Treatment 3 (Kentucky bluegrass + Redtop) 4) Treatment 4 (tall fescue + orchardgrass). There was no winterkilling or lodging problem at an altitude of 200 m. Plant heights in mixed pasture of Treatment 1, 2, 3, and 4 were 53.9, 58.2, 57.5, and 78.1 cm, respectively. Plant height was the highest in Treatment 4. Dry matter yield was in the following order : Treatment 4 > Treatment 3 > Treatment 2 > Treatment 1. In the first investigation regarding vegetation distribution, Bermudagrass ratios among grasses in Treatment 1 and Treatment 2 were 70% and 66.7%, respectively. Overall, other grasses showed poor growth. In the second investigation of vegetation distribution, Bermudagrass ratios among grasses in Treatment 1 and Treatment 2 were 80% and 60.7%, respectively. Crude protein content, neutral detergent fiber content, acid detergent fiber content, digestibility value, and nutritive values were the lowest in Treatment 4, followed by those in Treatment 1, Treatment 2 and Treatment 3.

본 연구는 오차드그라스와 톨 페스큐 혼파초지에서 비축 시기별(8월 1일, 15일, 30일) 으로 처리하여 11월 중순경(11.10∼11.12)에 수확할 때 목초의 비축시기에 따른 생산량과 목초의 사료 가치 등을 비교하기 위해 수행하였다. 목초 비축시기에 따른 오차드그라스와 톨 페스큐 혼파초지(동량 혼파초지)의 건물수량은 8월하순구가 2,983.0kg/ha으로 가장 높은 경향을 보였다. 목초의 비축시기가 늦어짐에 따라 목초의 생산량도 증가하였으나 유의성이 인정되지는 않았다. 조사료의 조단백질은 16.5∼18.16%으로 목초 비축시기별로 일정한 경향을 나타내지 않았다. NDF와 TDN는 비축시기가 늦을수록 증가하는 경향을 나타내었으나 유의성이 인정되지는 않았다. 반면에 ADF 비율은 목초 비축시기가 감소함에 따라 점차 감소하는 것으로 나타내었으나 유의성이 인정되지는 않았다. 무기물의 변화는 비축 기간이 증가할수록 P, Ca, Mg, Na, Zn이 증가하였고 반면에 Mn, Cu는 감소하는 경향을 나타내었다. 결과적으로 8월 초순부터 초지를 비축할 경우 고온으로 인한 생육 위축으로 목초의 수량증가는 기대하기 어렵다. 따라서 제주도에서 가을철에 활용하기 위한 초지를 비축할 경우에는 8월 하순 이후에 시작하는 것이 바람직할 것으로 사료된다.

This study was conducted to evaluate the chemical composition and physico-chemical meat quality properties for Jeju-horse (Jeju-horse×Thoroughbred) with different fattening periods (4-, 8- and 13.5-month). In chemical composition, the moisture contents were decreased as the fattening periods increased. The fat contents were 3.78% at 4-months and they were decreased such as 70∼76% at 13.5-months whereas the protein contents increased as the fattening period increased. The cooking loss was highest (33.41%) at 4-months group and decreased after that periods, however, there was no significant difference among 3 fattening period groups. The Warner-Bratzler shear force (WBS) values were lowest at 4-months group and tended to increase as the fattening period increased. In mineral contents, the contents of Fe, Na, Zn were significantly higher for 4-month group than 8- and 13.5-month group whereas the contents of Mg were significantly lower for 4-month group than 8- and 13.5-month group (p＜0.05). The results of the amino acid composition analysis showed that cystein, methionine, threonine, serine, glutamic acid, alanine, valine, lysine, histidine, arginine contents were significantly increased and tyrosine contents were significantly decreased as the fattening period increased (p<0.05). The contents of palmitic acid (C16:0) were highest at 4-month group and they decreased as the fattening period increased (p＜0.05). The contents of oleic acid (C18:ln9) were highest at 8-month group and they were lowest at 13.5-month group. The total contents of unsaturated fatty acids were significantly higher for 13.5-month group than those for 4-month groups (p＜0.05). In conclusions, the fat contents were decreased whereas the protein, Fe, Mg contents and WHC increased as the fattening periods increased. Overall contents of amino acids increased only except several amino acids. The total contents of unsaturated fatty acids were increased as the fattening period increased, however they were not significantly different when those were fattened more than 8-month. These results indicated that longer fattening period could be more effective to enhance horse meat quality.