Effects of Turnout to Pasture and Dietary Fat Supplementation on Milk Fat Composition and Conjugated Linoleic Acid in Dairy Cows     

Sigrid Agenäs  Kjell Holtenius  Mikko Griinari  Erling Burstedt 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):25-33

Turnout to pasture involves considerable changes in the feed intake and metabolism of dairy cows. The aim of this study was to investigate how these changes affect milk production and milk fat composition, in cows selected for high (HFI) or low (LFI) milk fat content producing the same yield of 4% fat-corrected milk. Furthermore, two different concentrates, with high or low inclusion of soya oil, were studied. The experiment was conducted with 44 multiparous mid-lactating cows over a 4 week period. Samples of milk and blood were obtained before turnout to pasture, during transition to pasture and when cows were adapted to pasture. Milk yield decreased with 3.6 kg energy-corrected milk (ECM) on average during the first 5 days after turnout to pasture. This decrease, together with a drop in plasma insulin and increased plasma non-esterified fatty acids (NEFA), indicated nutritional insufficiency at turnout to pasture. Milk fat composition changed towards more long-chain fatty acids (LCFA) and fewer de novo synthesized fatty acids. This was probably caused by an increased supply of LCFA of feed and body origin to the udder. LFI cows showed higher levels of conjugated linoleic acid at pasture than HFI cows.  相似文献   

Genetic Parameters for the Piglet Mortality Traits Crushing,Stillbirth and Total Mortality,and their Relation to Birth Weight     

Katja Grandinson  Mogens Sandø Lund  Lotta Rydhmer  Erling Strandberg 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(4):167-173

The aim of this study was to estimate genetic and phenotypic parameters for the three mortality traits crushing, stillbirth and total mortality in piglets, and their respective correlations with birth weight. Records were available from 11 016 Yorkshire piglets from 1046 first parity litters in a Swedish experimental herd. Each mortality trait was analysed jointly with birth weight, using bivariate models. Both mixed linear models and threshold models were used. The threshold models took environmental and maternal genetic effects into account, whereas the linear models also included a direct genetic effect of the piglet on its birth weight. The estimated heritabilities were low for all mortality traits (0.01-0.15), with the lowest estimate for crushing and the highest for stillbirth. The estimated environmental correlations between the different mortality traits and birth weight were negative. The estimated genetic correlations between crushing and birth weight (both direct and maternal effect) were also negative in both models, indicating that sows with low-weight piglets are more likely to crush piglets. However, the genetic correlations between stillbirth and birth weight (both direct and maternal effect) were positive. These results suggest that stillbirth and crushing are traits with different genetic backgrounds, and that genetically increasing the birth weight of the piglets may result in more stillborn piglets.  相似文献   

Genetic Relations between Reproduction,Chick Weight and Maternal Egg Composition in a White Leghorn Line     

Camilla Hartmann  Erling Strandberg  Lotta Rydhmer  Kjell Johansson 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(2):91-101

Selection is a viable way to increase egg dry matter, an important trait for the egg processing industry, but simultaneously a change in the embryonic environment takes place. The main purpose of this study was to estimate genetic parameters for the percentage of fertile eggs of eggs set (FERT), percentage of eggs hatched of fertile eggs (HATCH), percentage of live chicks 2 weeks post-hatch of hatched eggs (SURV/h) and of fertile eggs (SURV), and their genetic correlations with egg weight, albumen weight, yolk weight, yolk proportion, albumen dry matter and mean chick weight in a White Leghorn selection line. Direct and maternal heritabilities were low for FERT, HATCH and SURV, and non-existent for SURV/h. All direct-direct genetic correlations between reproduction traits and egg composition traits were not significant. Maternal-direct genetic correlations between HATCH and egg weight, albumen weight, yolk weight, yolk proportion and albumen dry matter were - 0.22, - 0.30, 0.28, 0.52 and 0.26, respectively. Similar correlations were found between SURV and egg composition traits. No significant genetic relationship was found between chick weight and post-hatch survival. In conclusion, within the range of values for egg composition in this study, selection for an increased egg dry matter should not impair reproduction.  相似文献   

Plasma lactate concentrations in free-ranging moose (Alces alces) immobilized with etorphine     

Henning A Haga DVM  PhD    Sandra Wenger† DVM  MScWAH  Diplomate ECVAA    Silje Hvarnes‡ DVM    Øystein Os‡ DVM    Christer M Rolandsen§¶ MSc  & Erling J Solberg§ PhD 《Veterinary anaesthesia and analgesia》2009,36(6):555-561

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Fall frost resistance in willows used for biomass production. II. Predictive relationships with sugar concentration and dry matter content     

Ogren E 《Tree physiology》1999,19(11):755-760

The accumulation of sugars and dry matter in stems in fall was examined in relation to frost hardening in eight willow clones (six clones of Salix viminalis L. and one clone each of S. viminalis x S. schwerenii E. Wolf and S. dasyclados Wimm.). Evidence is presented that three sources of variation in fall frost resistance among the eight clones could be assessed from an analysis of stem composition. First, the pre-hardening value of frost resistance could be assessed from the total sugar concentration. Second, the start of induction of apical growth cessation and hence frost hardening could be distinguished by a stepwise increase in sucrose-to-glucose ratio. Third, the progress of frost hardening during its first phase could be followed from a proportional rise in total sugar concentration and, even more accurately, from a proportional rise in dry-to-fresh weight ratio. In contrast, the second phase of frost hardening was largely uncoupled from sugar and dry matter accumulation. Raffinose and sucrose accumulation seemed to be under differential environmental controls. Sucrose accumulation started with the initiation of growth cessation controlled by photoperiod, whereas raffinose accumulation started with falling temperatures later on. Starch reserves that built up in stems in early fall were partially mobilized later on to support sugar accumulation. In contrast to stems, leaves did not exhibit a preferential accumulation of sucrose in fall.  相似文献   

Reproductive performance of Ankole cattle and its crossbreds in Rwanda     

Manzi  Maximillian  Rydhmer  Lotta  Ntawubizi  Martin  Karege  Callixte  Strandberg  Erling 《Tropical animal health and production》2019,51(1):49-54

Tropical Animal Health and Production - The aim of this study was to assess the reproductive performance of Ankole cattle and its crossbreds with Friesian (F), Jersey (J), and Sahiwal (S). The...  相似文献   

Melanized focal changes in skeletal muscle in farmed Atlantic salmon after natural infection with Piscine orthoreovirus (PRV)     

Hvard Bjrgen  Randi Haldorsen   yvind Oaland  Agnar Kvellestad  Dhamotharan Kannimuthu  Espen Rimstad  Erling Olaf Koppang 《Journal of fish diseases》2019,42(6):935-945

Melanized focal changes in skeletal muscle of farmed Atlantic salmon (Salmo salar) are a major quality problem. The aetiology is unknown, but infection with Piscine orthoreovirus (PRV) has been associated with the condition. Here, we addressed the pathogenesis of red and melanized focal changes and their association with PRV. First, a population of farmed fish (PRV‐negative prior to sea transfer) was sequentially investigated throughout the seawater period. The fish were autopsied and tested for PRV infection. Muscular changes were described by macroscopy and histology, and a classification system was established. Second, in an experimental infection trial, PRV was injected intramuscularly to induce changes. The farmed fish was gradually infected with PRV. Red focal changes occurred throughout the observation period with a low prevalence regardless of PRV status. Melanized changes were highly diverse and their prevalence increased during the trial. Changes of low macroscopic grade and histological category were more prevalent in PRV‐negative fish. Diffuse granulomatous melanized changes only occurred after PRV infection. No muscular changes were observed in the experimentally challenged fish. Our studies do not indicate that PRV infection causes red focal changes, but seems important in the development of granulomatous melanized changes.  相似文献   

Isolation and characterization of Indian betanodavirus strain from infected farm‐reared Asian seabass Lates calcarifer (Bloch, 1790) juveniles     

Kollanoor Riji John  Mulloorpeedikayil Rosalind George  Bridget Jeyatha  Rengarajan Saravanakumar  Pitchaimani Sundar  Karingalakkandy Poochirian Jithendran  Erling Olaf Koppang 《Aquaculture Research》2014,45(9):1481-1488

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油脂天然抗氧化剂研究——Ⅰ、茶叶提取物抗油脂氧化的效果     

胡慰望  谢笔钧  杨尔宁  钱春华  孙智达 《华中农业大学学报》1987,(4)

用茶叶中提取的多酚类物质(TPE)加入油脂中,用烘箱静置法观察油脂过氧化值(POV)的变化。结果表明,茶叶多酚类提取物添加量为0.03-0.04%(按油脂重量计),对猪油、精炼菜油、色拉油和精炼豆油的抗氧化效果相当于0.02%BHT的1.3-2倍和0.02%DL,α-生育酚的4倍,且具有良好的抗氧化稳定性。在有0.02-0.04%柠檬酸增效剂存在下,TPE的抗氧化效果可提高1.6-3倍。红外光谱分析证明,TPE中多酚类组分和柠檬酸产生氢键缔台,形成大的氢给予体,因而增强了抗油脂氧化的稳定性。柱层析分离TPE总共得到六个部分,其中二个部分抗油脂氧化效果最佳。  相似文献   

Piscine orthoreovirus (PRV) in red and melanised foci in white muscle of Atlantic salmon (Salmo salar)     

H?vard Bj?rgen  ?ystein Wessel  Per Gunnar Fjelldal  Tom Hansen  Harald Sveier  H?kon Rydland S?b?  Katrine Bones Enger  Eirik Monsen  Agnar Kvellestad  Espen Rimstad  Erling Olaf Koppang 《Veterinary research》2015,46(1)

Melanised focal changes (black spots) are common findings in the white skeletal muscle of seawater-farmed Atlantic salmon (Salmo salar). Fillets with melanised focal changes are considered as lower quality and cause large economic losses. It has been suggested that red focal changes (red spots) precede the melanised focal changes. In the present work, we examined different populations of captive and wild salmon for the occurrence of both types of changes, which were investigated for the presence of different viruses by immunohistochemistry and RT-qPCR. The occurrence of red or melanised foci varied significantly between the populations, from none in wild fish control group, low prevalence of small foci in fish kept in in-house tanks, to high prevalence of large foci in farm-raised salmon. Large amounts of Piscine orthoreovirus (PRV) antigen were detected in all foci. No other viruses were detected. Red focal changes contained significantly higher levels of PRV RNA than apparently non-affected areas in white muscle of the same individuals. Some changes displayed a transient form between a red and melanised pathotype, indicating a progression from an acute to a chronic manifestation. We conclude that PRV is associated with the focal pathological changes in the white muscle of farmed Atlantic salmon and is a premise for the development of focal melanised changes.  相似文献