Retrospective surveillance of metabolic parameters affecting reproductive performance of Japanese Black breeding cows

This retrospective study was conducted to confirm the relationship between pre- and postpartum metabolic parameters and postpartum reproductive performance and to clarify seasonal characteristics of the metabolic parameters by using our metabolic profile test (MPT) database of Japanese Black breeding herds. In evaluation 1, MPT databases of blood samples from multiparous cows collected prepartum and postpartum were divided into two groups according to calving interval, and each MPT parameter was compared. In evaluation 2, the same MPT databases used in evaluation 1 were divided into two groups according to the sampling period. Significant differences were found in the prepartal total protein and postpartal γ-glutamyltransferase in evaluation 1. In evaluation 2, significant differences were found in the prepartal and postpartal total protein, albumin/globulin ratio, and glucose. Clear seasonal differences in MPT results emphasized the usefulness of the MPT in breeding cattle herds fed home-pasture roughage and suggest that unsatisfactory reproductive performance during hot periods reflects inadequate nutritional content of the diet and possible reduced feed intake due to heat stress.     

Influence of feeding methods on blood biochemical parameters of Japanese Black breeding herd

The aim of this study was to investigate the effect of different feeding methods on blood biochemical parameters by using a total of 32 Japanese Black breeding cows. The diet (silage) was distributed at a rough estimate for 18 days (FN period), and stanchions were not used in this period. After the FN period, the cows were separated in stanchions for feeding and were fed specified amount of silage by using scales on a feeder wagon, which was determined according to the diet formulation and average body weight of cows, for 30 days (FW period). On the last day of the two experiment periods, the body weight of all cows was recorded and blood samples were collected from 10 randomly selected cows. β‐hydroxybutyric acid and albumin (Alb) levels were significantly higher after the FW period than after FN period. The variation of glucose, Alb, calcium and lactic acid was significantly smaller after the FW period. Several blood parameters of the FW period were approximately the appropriate range of a Japanese Black breeding herd in the dry period. Our results suggest that the feeding method by use of a stanchion and proper diet formulation affects blood biochemical parameters and improves nutritional conditions for breeding cows.     

Carrier rate of the c.235G>C mutation in the bovine isoleucyl-tRNA synthetase (IARS) gene of Japanese Black cows at Kagoshima prefecture, Japan,and analysis of the metabolic profiling and reproductive performance of heterozygous cows

Bovine isoleucyl-tRNA synthetase (IARS) disorder, a major cause of weak calf syndrome, is caused by a homozygous missense (c.235G>C) mutation in the bovine IARS gene of Japanese Black (JB) cattle, which was identified in 2013. However, the extent to which the carrier rate has changed at Kagoshima prefecture, Japan, and whether the carrier status is associated with any clinical or reproductive problems, have yet to be ascertained. In this study, using a real-time polymerase chain reaction-based genotyping assay, we determined the carrier rate in a regional JB cow population at Kagoshima prefecture. Comparative analyses were performed on the metabolic profile test (MPT) results and reproductive performance data obtained for heterozygous carrier and homozygous wild-type cows. In 2009 and 2018, DNA samples were collected from 130 and 462 clinically healthy JB cows, respectively, in Kagoshima prefecture. MPT results and reproductive performance data were evaluated for 62 cows, comprising four heterozygous carriers and 58 wild-type cows. Genotyping revealed that the carrier rate was 6.9% in 2009 and 1.5% in 2018, the difference of which was statistically significant (P<0.005). There were no statistically significant differences between the carrier and wild-type cows with respect to either MPT results or reproductive performance, indicating that the carrier cows have necessary IARS activity to maintain minimal health and reproductive potential.     

不同蛋白质水平日粮对中国荷斯坦奶牛生产性能、氮消化和血液生化指标的影响

旨在研究饲粮不同粗蛋白质(CP)水平对中国荷斯坦奶牛乳尿素氮(MUN)、氮(N)消化及血液尿素氮(BUN)的影响。采用4×4拉丁方设计,16头经产中国荷斯坦奶牛随机分为4个处理。4个处理的饲粮能量相近,CP水平分别为12. 72%、13. 52%、14. 43%和15. 37%。试验分为4个周期,每个周期15 d,后5 d为样品收集期。奶样收集3 d,同时收集粪便,每期最后1 d晨饲前空腹采集血样。每天测量产奶量和干物质摄入量。结果:不同蛋白水平日粮奶牛干物质采食量(DMI)和产奶量组间差异不明显(P>0. 05),除了MUN随着饲粮CP水平的增加呈现增加趋势以外,其他乳成分影响不显著(P>0. 05),高蛋白质水平组MUN明显高于低蛋白组(P<0. 05)。随着饲粮CP水平的提高,氮的摄入量明显增加(P<0. 05),同时N的排泄量和消化率也不断增加,但组间无显著差异(P>0. 05)。BUN和MUN变化趋势基本一致,高蛋白质组的BUN明显高于低蛋白质组(P<0. 05),而对其他血液指标的影响不显著(P>0. 05)。在本试验条件下,不同蛋白质水平日粮能够影响中国荷斯坦奶牛MUN、BUN的变化,且两者变化趋势一致,而对产奶量、N消化率影响不明显,MUN可以代替BUN成为检测奶牛蛋白质营养状况的指标之一。     

青贮紫花苜蓿对奶牛生产性能、尿素氮和血液生化指标的影响

在苜蓿（Medicago sativa）中添加5%的糖蜜,并进行苜蓿大窖青贮和饲喂试验,研究以青贮苜蓿（试验组）替代相同干物质量（DM）的苜蓿干草（对照组）对奶牛生产性能、尿素氮及血液生化指标的影响。结果表明,给奶牛饲喂苜蓿青贮饲料有利于提高奶牛干物质采食量（Dry Matter Intake,DMI）、日产奶量和乳脂率,试验后期乳蛋白含量有所下降,但差异均不显著（P0.05）;乳尿素氮（Milk Urea Nitrogen,MUN）及尿液尿素氮（Urinary Urea Nitrogen,UUN）含量均呈现下降趋势,血浆尿素氮（Plasma Urea Nitrogen,BUN）先下降后上升,其中试验组MUN和BUN低于对照组（P0.05）,UUN则高于对照组,在试验后期,试验组和对照组UUN分别为48.35和27.52 mmolL-1,差异显著（P0.05）;谷丙转氨酶（Alanine Aminotransferase,ALT）、谷草转氨酶（Aspartate Transaminase,AST）和碱性磷酸酶（Alkaline Phosphatase,ALP）含量均为试验组高于对照组,差异不显著（P0.05）;血浆中总蛋白（Albumin,ALB）和葡萄糖（Glucose,GLU）含量试验组逐渐降低,且低于对照组,但差异不显著（P0.05）;胆固醇（Chinese Hamster Ovary,CHO）的含量试验组逐渐升高,对照组逐渐降低,在试验后期分别为3.64和2.82 mmolL-1（P=0.059）,差异最大。总之,饲喂苜蓿青贮饲料有利于改善奶牛的生产性能和机体代谢能力,由于美拉德反应的发生,试验后期降低了苜蓿青贮饲料营养物质在奶牛体内的代谢利用效果。     

Digestibility of common reed (Pharagmites communis Trin.) silage as ruminant feed and effects of inclusion levels in the diet of breeding cows on feed intake,ruminal fermentation and blood metabolites

To examine the digestibility of common reed (Pharagmites communis Trin.) silage and effects of inclusion levels in the diet of breeding cows on nutrient intakes, ruminal fermentation and nutrient status, two digestion trials using four sheep and cows, respectively, at the maintenance stage were conducted. In the trial using sheep, common reed silage contained 20% crude protein (CP) and 50% total digestible nutrients (TDN) on a dry matter basis. In the trial using cows, treatments were the control (92.4% Sudangrass hay and 7.6% soybean meal) and CS25, CS50 and CS80 (replacing 25%, 50%, and 80% of the control with silage, respectively). The intake and sufficiency rate of CP increased by increasing the silage level in the diet (P < 0.05), and the CP requirements of cows at maintenance was satisfied in CS80. In contrast, the sufficiency rate of TDN decreased in CS80, although it was 99.8%. Ruminal pH and NH₃‐N concentration changed among the treatments (P < 0.05); however, the blood metabolites were not affected by silage. The results indicated that including common reed silage of up to 80% in the diet of breeding cows was possible and did not have adverse effects on the blood metabolites.     

Effects of inclusion levels of pelleted silvergrass (Miscanthus sinensis Andress.) in the diet on digestibility,chewing activity,ruminal fermentation and blood metabolites in breeding Japanese Black cows

To examine the effects of inclusion levels of pelleted silvergrass (PS) in the diet on digestibility, ruminal fermentation and nutrient status of breeding Japanese Black cows, four cows were allotted to a 4 × 4 Latin square design experiment. Treatments were control fed a diet consisting of 89.4% Sudangrass hay and 10.6% soybean meal on a dry matter (DM) basis, and PS18, PS27 and PS45 fed the diet replaced with 18%, 27% and 45% of control with PS, respectively. The total digestible nutrients (TDN) content of PS was 45.6% on a DM basis. The TDN intakes were significantly decreased by increasing PS level in the diet (P < 0.05), but were higher than the TDN requirement of maintenance cows in all treatments. The total chewing time was decreased significantly by increasing PS level in the diets (P < 0.05). However, the pH and concentration of volatile fatty acid in the ruminal fluid and serum metabolite concentrations were not significantly different among the treatments. The results suggested that including PS up to 45% in the diet did not have adverse effects on the ruminal fermentation and nutrient status in breeding Japanese Black cows at the maintenance stage.     

Effect of probiotics on blood fatty acid metabolism during the late middle stage of fattening period in Japanese Black cattle

This study was conducted to investigate the effects of probiotics administration on fatty acid metabolism in Japanese Black cattle as per changes in blood fatty acid concentrations and blood biochemical tests. Eighteen clinically healthy Japanese Black female fattening cattle bred on the same fattening farm were randomly classified into the probiotics administration group (n=9) or the control group (n=9). In the probiotics administration group, 50 g of probiotics were started per animal per day at the age of 18 months, and the administration period was 2 months from the start date of the study. Blood was collected twice before starting the probiotics administration and at 2 months after starting the probiotics administration. In the probiotics administration group, palmitic, linoleic, arachidonic and α-linolenic acid tended to be higher at the end of the administration compared with those before probiotics administration. Additionally, as a result of multiple comparison test, monounsaturated fatty acids at Post was significantly higher, and the ω6 / ω3 ratio was significantly lower than in the control group. Vitamin A, E and albumin were significantly higher at the end of the administration than in the control group. In this study that administering probiotics to Japanese Black cattle in the late middle stage of fattening period did not have a significant effect on fatty acid metabolism during feed digestion and absorption, but suggested that may alter some blood fatty acids concentrations.     

日粮粗纤维水平对鹅生产性能、代谢激素和生化指标的影响

以500只29日龄生长鹅为试验动物,以砻糠和玉米秸秆为主要纤维源,进行28 d的饲养试验,研究日粮在等能量等蛋白水平下,不同粗纤维(crude fiber,CF)水平(3%、5%、7%、9%和11%)对鹅生产性能、代谢激素和血清生化指标的影响。结果表明:随着日粮粗纤维水平的增加,生长鹅的日采食量呈增加的趋势,但各处理组间差异不显著(P>0.05),饲料转化率和日增重呈先增加后减少的趋势(P<0.05);5?组与7?组生长鹅的生产性能最佳,与11?组相比,日增重分别提高了22.60%与24.25%(P<0.05),饲料转化率分别改善了22.65%与21.74%(P<0.05);日粮粗纤维水平对生长鹅血清中血糖(GLU)、碱性磷酸酶(ALP)、生长激素(GH)和IGF-I有显著影响(P<0.05),而对尿酸(UA)、总蛋白(TP)、谷丙转氨酶(ALT)、谷草转氨酶(AST)、胰高血糖素(GLU)、胰岛素(INS)、促甲状腺素(TSH)、三碘甲状腺原氨酸(T3)和甲状腺素(T4)均无显著影响(P>0.05)。     

Effect of feeding wood kraft pulp on the growth performance,feed digestibility,blood components,and rumen fermentation in Japanese Black fattening steers

This study aimed to examine the effects of feeding kraft pulp (KP) on the growth performance, feed digestibility, and rumen fermentation of Japanese Black fattening steers. Ten Japanese Black fattening steers (aged 26 months) were randomly divided into control and KP groups. The control group (n = 5) was fed concentrate feed without KP, and the KP group (n = 5) was fed concentrate feed containing 10% KP. Both the groups were provided rice straw as roughage. The experiment was conducted over a period of 12 weeks. There was no significant difference in dry matter intake, daily body weight gain, and nutrient digestibility between both groups. No difference was observed in the ruminal concentrations of volatile fatty acids among the groups. At weeks 8 and 12 after the onset of the experiment, the acetate‐to‐propionate ratio in the ruminal fluid of the KP group was significantly higher than that of the control group. The average daily pH of ruminal fluid and activity of ruminal lipopolysaccharide did not differ between the groups. Our results suggested that the growth performance and feed digestibility in the Japanese Black fattening steers were not influenced by replacing concentrate feed with KP.     

赖氨酸水平对仔猪生长表现、血清尿素氮及游离赖氨酸浓度的影响

试验选用90头体重为7.8±1.0kg的三元(大白×长白×北京黑)杂种仔猪,通过研究不同饲粮赖氨酸水平(1.0%、1.1%、1.2%、1.4%和1.5%)对仔猪生长表现、血清尿素氮及游离赖氨酸浓度的影响,确定仔猪适宜的赖氨酸需要量。结果表明,在中国实际生产条件下,8～20kg仔猪的赖氨酸建议需要量为1.1%～1.2%;且随饲粮赖氨酸水平提高,仔猪料重比呈线性降低(P<0.0004),每克赖氨酸增重量也呈线性降低(P<0.001),血清游离赖氨酸浓度呈线性升高(P<0.006)。     

Influence of organic phosphorus on reproductive performance and metabolic profiles of anoestrous Farafra ewes in subtropics at the end of breeding season

The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n  = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p  < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p  < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p  < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p  < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p  < .05) and monocytes (2.93 ± 0.13; p  < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer.     

Effects of reducing dietary crude protein on growth performance, odor gas emission from manure and blood urea nitrogen and IGF-1 concentrations of serum in nursery pigs

Two experiments were conducted to investigate the effects of reducing dietary crude protein on growth performance, odor gas emission from manure and blood urea nitrogen and IGF-1 concentrations of serum in nursery pigs. In experiment 1, the dietary treatments were (i) CON (CP 19.5%) and (ii) T1 (CP 16.0%). In feces samples, NH₃, H₂S, acetic acid and butyric acid emissions during the T1 treatment were lower than during the CON treatment ( P  < 0.05). In feces-urine samples, NH₃ emission during the T1 treatment was lower than during the CON treatment ( P  < 0.05). In experiment 2, 28 crossbred (Landrace × Yorkshire × Duroc) pigs (13.58 ± 0.10 kg) were used for a 42-day growth trial. Throughout the entire experimental period, ADG and ADFI of the CON treatment were higher than the T1 treatment ( P  < 0.05). On day 14, N digestibility in pigs fed the CON diet was higher than that of pigs fed the T1 diet ( P  < 0.05). On days 28 and 42, DM digestibility of the CON diet was greater than the T1 treatment ( P  < 0.05). On dat 42, serum BUN concentration of pigs fed the CON diet was higher than that of pigs fed the T1 diet ( P  < 0.05). In conclusion, these results indicate that reduction in dietary CP concentration decreased NH₃, H₂S and VFA emissions in feces and growth performance in nursery pigs.