Dynamic changes of fatty acids and minerals in sow milk during lactation

The objective of the present study was to explore the changes in fatty acids (FAs) and minerals composition in sow milk in order to improve the knowledge about FAs and mineral requirements for piglets. The FAs and minerals composition in the sow milk samples which were collected from ten sows during a period of 16 days of lactation was analysed. The proportion of FAs in sow milk has a significant increase in C8:0, C10:0, C12:0, C14:0, C16:0, C14:1 and C16:1 FAs and the sum of saturated fatty acids (SFAs) according to the lactation period (p < 0.05). The proportion of C18:2 cis‐9,12 FA and the sum of polyunsaturated fatty acids (PUFAs) significantly decreased with the advancing of lactation (p < 0.05). The concentrations of minerals, including potassium, copper, manganese and zinc, were higher on day 1 and day 2 than those on day 13 and day 16 (p < 0.05). On the contrary, the lowest concentrations of calcium, sodium, magnesium and iron and the lowest molar calcium: phosphorus ratio emerged in colostrum (p < 0.05). In summary, our results demonstrated FAs profile and minerals concentrations were changed with lactation period. Better understanding of the changes of FAs and minerals may be valuable to swine nutritionists in the commercial industry. In addition, those results provided some meaningful information for sow's diet formulation during lactation.     

二花脸母猪泌乳期乳中乳铁蛋白分泌规律的研究

应用我们已建立的酶联免疫吸附分析 (ELISA)方法 ,研究二花脸母猪泌乳期乳中乳铁蛋白 (Lactoferrin,Lf)的分泌规律。采集分娩后的4头二花脸母猪在泌乳起始 48h内的连续乳样 (每小时采样 1次 )进行测定。结果显示 :刚分娩时乳中Lf浓度最高 ,为 1 2 66 59μg/mL ;随后开始下降 ,前 2 0h内下降较快 ,2 0h之后下降变缓 ;至第 48h ,浓度降为第 1小时的 53 %。对处于泌乳期前 30d内的 4头二花脸母猪连续乳样 (每天采集 1次 )和 1 0 2头二花脸母猪散点乳样 (每天随机采样 )的测定结果表明两者Lf的分泌规律基本相似 :分娩第 1天 ,Lf浓度最高 ;1周内迅速下降 ,第 7天降至第 1天的 2 5 % ;1周后下降缓慢 ;2周后趋于平稳。     

复方中草药添加剂对哺乳母猪泌乳力的影响

选用18头经产约克母猪,随机分为药物组和对照组,每组9头,用蒲公英、王不留行、漏芦、续断组成复方中草药添加剂对哺乳母猪进行20d的饲养试验。结果表明:药物组比对照组窝重提高15.04%(P<0.01),成活率提高6.03%(P<0.05),平均日增重提高6.47%(P<0.05)。     

Skim milk progesterone in pregnant cows from insemination throughout lactation

The skim milk progesterone profile was assessed by radioimmunoassay, without extraction, from the day of insemination (day 0) until the cows were dried off on day 225 of gestation. A total of 418 samples were collected from 154 pregnant Holstein cows. The daily variation in skim milk progesterone was recorded from day 1 until day 45 of pregnancy to detect the commencement of progesterone secretion from the corpus luteum after insemination. Subsequent determinations were made every 2 weeks from day 46 until lactation ceased. On the day of artificial insemination and for the first 2 days after insemination, all the cows had a basal progesterone concentration <0.1 ng/ml. A rise in progesterone (0.2±0.1 ng/ml) was first detected on the third day after insemination. The progesterone values then increased significantly (p<0.001) until day 15.The values then remained nearly constant (2.5–3.5 ng/ml) until day 106 of pregnancy, when they began to decline. Between days 120 and 180 of gestation, progesterone was significantly decreased (2.2–2.9 ng/ml) before it rose again to the previous plateau (3.5–3.9 ng/ml) around day 180. The progesterone concentration then remained at the higher level until the animals were dried off.Abbreviations AI artificial insemination - RIA radioimmunoassay     

香味剂对高温应激条件下母猪泌乳性能的影响

试验旨在研究高温应激条件下,日粮添加香味剂对母猪泌乳和产仔性能及仔猪生长性能的影响。选择平均胎次为2.5、妊娠110 d的母猪300头,随机分为3组,每组100头猪。采用单因素试验设计,共3种日粮,处理1组饲喂玉米-豆粕型基础日粮,处理2组在基础日粮中添加250 g/kg香味剂,处理3组在基础日粮中添加500 g/kg香味剂,试验由分娩当天开始,到断奶再发情结束。各组对母猪的采食量有显著影响,其中处理3组较处理1组和处理2组显著提高了母猪采食量(P <0.05),处理2组显著高于对照组(P <0.05)。与处理2组相比,处理3组使母猪的采食量提高了9.6%(P <0.05)。处理3组较处理2组及处理2组较处理1组显著提高了断奶后仔猪头数(P <0.05)。与处理2和处理1组相比,处理3组显著提高了泌乳期间仔猪的平均日增重(P <0.05),同时也显著提高了仔猪的断奶重(P <0.05)。处理1组呼吸频率最低(P <0.05),香味剂对直肠温度也有显著影响,处理2组和处理3组直肠温度显著高于处理1组(P <0.05)。综上所述,高温应激条件下,日粮添加香味剂可以提高母猪的采食量和泌乳性能,同时采食量的提高可以促进仔猪生长性能,降低热应激对母猪的负面影响。     

现代泌乳母猪的能量营养研究新进展

现代泌乳母猪的特点使得其要求更精细而严格的饲养管理条件,以及各营养物质尤其是能量的适量满足。文中从母猪泌乳期能量需要及泌乳期能量对繁殖性能影响方面着手,提出从全繁殖周期考虑合理供给能量,针对现代育种目标而制定相应营养供给的策略。     

泌乳期母猪的饲喂频率对其体况、生产和繁殖性能的影响

文章评估了哺乳期间母猪的饲喂频率(2或3次/d)对母猪体况、繁殖性能及仔猪生长性能的影响。试验选择68头母猪,随机分为8组(每组8~10头母猪),哺乳期间其中4组母猪每天饲喂2次,另外4组每天饲喂3次,母猪分为青年母猪(<2胎次)和老龄母猪(≥3胎次),试验结束后记录母猪体况评分、肩部组织病变、发情率、母猪生产及仔猪生长性能。结果显示:每天饲喂3次的母猪比饲喂2次的母猪采食量高(P<0.05),肩部组织病变低(P<0.05)。在每天饲喂3次的母猪中,青年母猪返情率为0%,老龄母猪返情率为29%,而在每天饲喂2次的母猪中,青年母猪发情率为20%,老龄母猪为5%。综上所述,在哺乳期,母猪每天饲喂3次较每天饲喂2次提高了采食量,对母猪体况评分和肩部组织病变有改善作用,同时也降低了年轻母猪的返情率。     

Season-dependent effect of daily frequency of feed distribution on the rate of feed consumption and reproductive performance in sows during lactation

The effects of the daily frequency of feed distribution (once, One; twice, Two; and four times, Four,) on the rate of feed consumption (RFC) and reproductive performance were investigated in Large White sows farrowing in the hot season from June to September (H sows) and in the rest of the year (R sows). The RFC was greater in feeding treatment Four than Two (P < 0.01) in H sows; however, bodyweight loss during lactation was not affected by the feeding treatment. No difference in effects of frequency of feed distribution for sows was observed on piglet growth. The survival rate of the piglets was not different between feeding treatments. The number of sows that came into estrus within 7 days post‐weaning was smaller in the feeding treatment Four than One (P < 0.05) in H sows and those of Four than One (P < 0.01) and Two (P < 0.05) in R sows. These results suggest that in sows during lactation increasing the daily frequency of feed distribution may have a negative effect on reproductive performance.     

Genome-wide association for milk production and lactation curve parameters in Holstein dairy cows

The aim of this study was to identify genomic regions associated with 305-day milk yield and lactation curve parameters on primiparous (n = 9,910) and multiparous (n = 11,158) Holstein cows. The SNP solutions were estimated using a weighted single-step genomic BLUP approach and imputed high-density panel (777k) genotypes. The proportion of genetic variance explained by windows of 50 consecutive SNP (with an average of 165 Kb) was calculated, and regions that accounted for more than 0.50% of the variance were used to search for candidate genes. Estimated heritabilities were 0.37, 0.34, 0.17, 0.12, 0.30 and 0.19, respectively, for 305-day milk yield, peak yield, peak time, ramp, scale and decay for primiparous cows. Genetic correlations of 305-day milk yield with peak yield, peak time, ramp, scale and decay in primiparous cows were 0.99, 0.63, 0.20, 0.97 and −0.52, respectively. The results identified three windows on BTA14 associated with 305-day milk yield and the parameters of lactation curve in primi- and multiparous cows. Previously proposed candidate genes for milk yield supported by this work include GRINA, CYHR1, FOXH1, TONSL, PPP1R16A, ARHGAP39, MAF1, OPLAH and MROH1, whereas newly identified candidate genes are MIR2308, ZNF7, ZNF34, SLURP1, MAFA and KIFC2 (BTA14). The protein lipidation biological process term, which plays a key role in controlling protein localization and function, was identified as the most important term enriched by the identified genes.     

从饲喂策略考虑提高母猪泌乳期采食量

母猪泌乳期高自由采食量(VFI)是其繁殖性能正常发挥的保证。为了提高母猪泌乳期VFI,文中分析了母体因素如品种、基因、带仔数、体况等对VFI的影响,提出着重从全繁殖周期饲喂策略考虑,以提高母猪泌乳期VFI。     

Effect of Prolactin Suppression on the Ovarian Activity in the Lactating Sow

The effect of prolactin suppression during lactation was studied in 6 sows nursing 5–10 piglets. In order to inhibit prolactin secretion a dopamin agonist (bromocriptine, Parlodel® “Sandoz”) was given per os from about 4 weeks after parturition until weaning 9–17 days later. Plasma prolactin and plasma progesterone were determined by radioimmunoassays. In all animals plasma prolactin was suppressed during the bromocriptine treatment. Two sows resumed ovarian activity during treatment as indicated by elevated plasma progesterone, probably as a result of the low plasma prolactin levels. The results suggest that the elevated plasma prolactin levels during lactation is one of the factors responsible for lactational an oestrus in the sow.     

改善母猪繁殖性能的营养调控措施

本文介绍了改善母猪繁殖性能的营养措施,包括在母猪日粮中添加有机铬、大豆黄酮、L-肉碱等。     

影响母猪泌乳期采食量的主要因素

本文从泌乳母猪采食量与生产性能的关系出发,阐述了提高母猪泌乳期采食量的重要性及影响采食量的主要因素。     

两种饲喂方式对哺乳母猪生产性能的影响研究

选取年龄、胎次、品种基本一致的哺乳母猪20头,随机分成对照组和试验组,试验分两批进行,每批10头。在相同的环境条件下,母猪自由饮水,饲喂同一哺乳母猪料。母猪分娩后4d内,采用原场饲养制度,逐步增加哺乳母猪采食量,第5天开始,对照组采用不限量饲喂,试验组采用限量和添加哺乳母猪补充料的饲喂方式,仔猪21日龄断奶。结果显示:两组仔猪21日龄的断奶窝重、母猪断奶后再发情时间和母猪哺乳失重等差异均不显著(P>0.05)。     

Shotgun proteomics of homogenate milk reveals dynamic changes in protein abundances between colostrum,transitional, and mature milk of swine

Milk is an easily digestible source of nutrients and bioactive factors, its composition reflects the neonate’s needs, and changes from colostrum to transitional and mature milk. Our objective was to measure milk fat, lactose, total carbohydrate, and protein content in parallel with global proteome of homogenate milk samples to characterize changes across the three phases of swine lactation. Milk samples were collected from multiparous sows (n = 9) on postnatal day 0 (D0; colostrum), 3 (D3; early transitional), 7 (D7; late transitional), and 14 (D14; mature). On D3, percent fat (16 ± 2.1) and lactose (3.8 ± 0.3) were higher (P < 0.05) than on D0 (10 ± 3.9 and 1.5 ± 0.3, respectively). Levels of fat and lactose were not different between D3 and D14. Percent total protein decreased (P < 0.05) between D0 (11 ± 2.1) and D3 (5 ± 0.7), but there was no significant change in percent protein between D3 and D14. Total carbohydrates increased (P < 0.05) between D3 (944 ± 353 µg/mL) and D14 (1,150 ± 462 µg/mL). Quantitative proteomic analysis using liquid chromatography tandem mass spectrometry (LC-MS/MS) of homogenate D0, D3, and D14 milk samples (n = 6) identified 772 protein groups which corresponded to 501 individual protein-coding genes. A total of 207 high confidence proteins were detected in n = 3 sows/day. Of the high confidence proteins, 81 proteins were common among all 3 days of lactation. Among the proteins that decreased between the days (false discovery rate; FDR < 0.05) were multiple apolipoproteins and XDH which decreased between D0 to D3. Proteins that increased across the days (FDR < 0.05) were complement factors and 14-3-3 proteins (YWHAQ, YWHAE). Our data provide a good characterization of milk proteome changes that likely reflect mammary function as well as the neonate’s phase-specific developmental needs. This data may be useful in developing approaches to enhance the health and welfare of swine.     

Plasma Prolactin in the Sow with Emphasis on Variation in Resumption of Ovarian Activity after Weaning

Plasma prolactin in the sow was studied during pregnancy, lactation and during the post weaning period. The ovarian activity was monitored hy progesterone determinations. In the pregnant sows (2 sows) there was a distinct increase in prolactin values ahout a week before parturition, amounting to maximum levels around parturition. A moderate decrease in prolactin values during the lactation period (3 sows) was observed. After weaning the prolactin values dropped immediately to basal levels. Of the 91 sows studied in the post weaning period 72 sows resumed cyclic ovarian function within normal time (10 days) after weaning while 19 sows had delayed resumption of ovarian activity. The prolactin patterns in sows with prolonged periods of ovarian inactivity were similar to those seen in normal sows. None of our results indicate that post weaning anoestrus is caused by prolonged hyperprolactinaemia after weaning.     

羟甲基丁酸钙盐对妊娠后期-哺乳期母猪繁殖性能、乳成分及仔猪生长性能的影响

文章旨在评估日粮中添加羟甲基丁酸钙盐对妊娠后期到哺乳期母猪繁殖性能、乳成分及仔猪生长性能的影响.试验选择32头胎次接近的二元母猪,随机分为2组,每组4个重复,每个重复4头猪.对照组母猪在妊娠后期和哺乳期饲喂基础日粮,处理组母猪在妊娠和哺乳期饲喂基础日粮+8?mg/kg羟甲基丁酸钙,试验从分娩前6?d到仔猪21?d断奶....     

Untersuchungen über Rassenunterschiede in der Milchleistung beim Schwein I. Mitteilung: Methodik des maschinellen Milchentzuges und Milchmengenleistung

Inhalt: Die vorliegende Untersuchung stellt einen Beitrag zur Methodik des maschinellen Milchentzuges beim Schwein dar. Mittels einer eigens hierzu entwickelten Melkmaschine wurde die Milchleistung der in ihren Muttereigenschaften stark differierenden Rassen Pietráin (PI) und Deutsches Edelschwein (DE) ermittelt. Der Milchentzug erfolgte in 2-stündigen Kontrollabschnitten an den Laktationstagen 3, 7,14, 21 und 28. Bei DE kam es während der 4wöchigen Laktationsphase zu einer gleichmäβigen Steigerung der Milch-sekretion von 5,05 1 am 3. Tag auf 12,8 l am Tag 28. Die Sekretionsrate der Rasse PI folgte diesem Verlauf, quantitativ um 2 bis 3 l/d reduziert, bis zu einem Maximum am 14. Laktationstag. Danach sank sie wieder ab. Am Tag 28 betrug der Leistungsunterschied zwischen beiden Rassen über 5 l/Tag. Mit dieser überlegenen Milchsekretionsrate zogen die DE-Sauen 3 Ferkel/Wurf mehr aufals die PI. Auch nach der Standardisierung derFerkelzahl zu Untersuchungsbeginn auf n = 10 blieb die Direrenz zugunsten der Edelschweine signifikant erhalten. Über die Milchinhaltsstoffe und ihre Abhängigkeit von Rasse und Laktationstag sowie ihre Bedeutung für die Lebendmasseentwicklung der Ferkel wird in der II. Mitteilung berichtet. Contents: Investigations on breed differences in milk yield of swine. I. comittment: methodology of mechanical milking and milk yield. This paper deals with the methodology of mechanical milking of sows. By a milking machine, especially developed herefore, milk yields of the breeds Pietrain (PI) and German Large White (DE) which differ a lot in weaning performance, were investigated. Milk was taken in two-hourly control intervalls on the days 3,7,14,21 and 28 of lactation. During this period of 4 weeks, DE showed a continuous increase in milk yield from 5.05 l on day 3 to 12.8 l on day 28. Secretion rate of PI followed parallel with a quantitative decrease of 2 to 3 liters/day, till a maximum was reached on day 14. Then lactation rates decreased. The difference in yield performance between the two breeds was about 5 l on day 28. This superior milk performance of the DE-sows allowed them to wean 3 piglets per litter more than PI. The advantage of DE over PI stays even after standardization of the litter size on n = 10 piglets. Milk composition, its relation towards breed and lactation day and its meaning for the litter performance will be topic of the second comittment.     

丙酸钙对泌乳早期奶牛泌乳性能和代谢产物的影响

选用32头经产奶牛,根据泌乳期、上个泌乳期305 d产奶量和预产期,采用随机区组设计分为4组,对照组饲喂基础日粮,处理1、2、3组分别在基础日粮基础上添加丙酸钙100、200、300 g/d.结果显示,日粮添加丙酸钙对奶牛的采食量、乳脂率、乳蛋白率、乳糖率和乳干物质率无显著影响,200、300 g/d组产奶量和饲料转化效率显著高于对照组(P<0.05).200、300 g/d组血浆葡萄糖和胰岛素浓度显著高于对照组(P<0.05),而血浆游离脂肪酸和β-羟丁酸浓度显著低于对照组(P<0.05);200、300 g/d组尿酮浓度显著低于对照组和100 g/d组(P<0.05).试验结果表明,丙酸钙适宜添加量为200 g/d.