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M. De Vos L. Che V. Huygelen S. Willemen J. Michiels S. Van Cruchten C. Van Ginneken 《Journal of animal physiology and animal nutrition》2014,98(4):609-619
Selection for hyperprolific sows, as a means of increasing litter size and profit, has resulted in an increased number of low‐birthweight (LBW) piglets. These LBW piglets might suffer from increased morbidity and mortality during the early neonatal period. In addition, they show reduced growth performance, meat and carcass quality, which leads to an important economic loss for the farmer in the post‐natal period. Therefore, nutritional interventions can be undertaken to prevent and rear LBW piglets. In the first part of this review, the preventive strategies at the sow level will be discussed. Approaches in preventing LBW piglets are to optimize the intrauterine environment via supplementing the sow during gestation. In the second part of this review, the interventions at the piglet level will be described. To increase the survival and growth rates of LBW piglets, one must focus on ensuring adequate colostrum and milk intake. Interventions include supplementing piglets, split nursing, split weaning and cross‐fostering. Additional interventions increasing the probability of optimal post‐natal food intake will be discussed. 相似文献
24.
Effect of intratesticular inoculation with Aujeszky's disease virus on genital organs of boars 总被引:1,自引:0,他引:1
Ten 8-10-month-old Belgian Landrace boars were intratesticularly inoculated with 500 TCID50 of a virulent Belgian Aujeszky's disease virus (ADV) isolate (75V19) in 0.1 ml volume. One control boar was similarly inoculated with phosphate-buffered saline solution. The genital organs of six inoculated boars were examined by virus isolation and immunofluorescence. In spite of high virus titers, the fluorescence in the testicles remained limited to a few small foci in the interstitial connective tissue and tunica albuginea at or close to the inoculation site. Neither virus replication, necrosis nor inflammatory lesions could be demonstrated in the epithelium of the seminiferous tubules. However, virus replication was regularly demonstrated in the serosa covering testicles, plexus pampiniformis, ductus deferens and tunica vaginalis. Virus was also isolated from the scrotal fluid. It is suggested that the serosa is the primary target tissue for ADV. The other four boars were inoculated to study the effect of ADV on semen. Severe morphologic alteration and lowered sperm cell concentrations were observed during several weeks after inoculation or until slaughter at 47, 53 and 58 days post inoculation. Virus was isolated from semen of only two out of four boars examined at 9 and 10 days post inoculation. 相似文献
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In vitro simulations of the gastric and small intestinal fermentation with varying doses of carvacrol, thymol, eugenol and trans-cinnamaldehyde and binary combinations thereof were carried out to calculate dose–response equations for the antimicrobial effect against the main pig gut flora components. Interaction effects were evaluated following the isobole method. In gastric simulations eugenol and trans-cinnamaldehyde showed clearly less inhibitory activity towards lactobacilli than carvacrol and thymol, which could also be observed in the small intestinal simulations. The minimum concentration for carvacrol, thymol, eugenol and trans-cinnamaldehyde in small intestinal simulations to reduce the number of total anaerobic bacteria compared to control with a probability of 99.7% was 255, 258, 223 and 56 mg/l respectively. This strong activity of trans-cinnamaldehyde was due to its effect against coliform bacteria; a dose of 104 mg/l gave a reduction of 1 log CFU/ml vs. 371, 400 and 565 mg/l for carvacrol, thymol and eugenol respectively. Few combinations demonstrated synergism; most mixtures showed zero interaction or antagonism. Only carvacrol + thymol was slightly synergistic. 相似文献
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The SALTIRSOIL model predicts soil salinity, sodicity and alkalinity in irrigated land using basic information on soil, climate, crop, irrigation management and water quality. It extends the concept of the WATSUIT model to include irrigation and crop management practices, advances in the calculation of evapotranspiration and new algorithms for the water stress coefficient and calculation of electrical conductivity. SALTIRSOIL calculates the soil water balance and soil solution concentration over the year. A second module, SALSOLCHEM, calculates the inorganic ion composition of the soil solution at equilibrium with soil calcite and gypsum at the soil’s CO2 partial pressure. Results from comparing predicted and experimentally determined concentrations, observations and predictions of pH, alkalinity and calcium concentration in calcite‐saturated solutions agree to the second significant figure; in gypsum‐saturated solutions the standard difference between observations and predictions is <3% in absolute values. The algorithms in SALTIRSOIL have been verified and SALSOLCHEM validated for the reliable calculation of soil salinity, sodicity and alkalinity at water saturation in well‐drained irrigated lands. In simulations for horticultural crops in southeast Spain, soil solution concentration factors at water saturation, quotients of electrical conductivity (EC25) at saturation to electrical conductivity in the irrigation water, and quotients of sodium adsorption ratio (SAR) are very similar to average measured values for the area. 相似文献
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Thomas R. De Ridder Justine E. Campbell Cheryl Burke‐Schwarz David Clegg Emily L. Elliot Samuel Geller Wendy Kozak Stephen T. Pittenger Jennifer B. Pruitt Jocelyn Riehl Julie White Melissa L. Wiest Chad M. Johannes John Morton Pamela D. Jones Peter F. Schmidt Victoria Gordon Paul Reddell 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2021,35(1):415-429
29.
Bianca Ferreira Olivieri Camila Urbano Braz Fernando Brito Lopes Elisa Peripolli Rafael Medeiros de Oliveira Silva Rosana Ruegger Pereira da Silva Corte Lucia Galvo de Albuquerque Anglica Simone Cravo Pereira Nedenia Bonvino Stafuzza Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2021,138(1):80-90
The aim of this study was to identify differentially expressed genes (DEG) in the Longissimus thoracis muscle of Nelore cattle related to fatty acid (FA) profile through RNA sequencing and principal component analysis (PCA). Two groups of 10 animals each were selected containing PC1 and PC2 extreme DEG values (HIGH × LOW) for each FA group. The intramuscular fat (IMF) was compared between cluster groups by ANOVA, and only the sum of monounsaturated FA (MUFA) and ω3 showed significant differences (p < .05). Interestingly, the highest percentage (95%) of phenotypic variation explained by the sum of the first two PC was observed for ω3, which also displayed the lowest number of DEG (n = 1). The lowest percentage (59%) was observed for MUFA, which also revealed the largest number of DEG (n = 66). Since only MUFA and ω3 exhibited significant differences between cluster groups, we can conclude that the differences observed for the remaining groups are not due to the percentage of IMF. Several genes that have been previously associated with meat quality and FA traits were identified as DEG in this study. The functional analysis revealed one KEGG pathway and eight GO terms as significant (p < .05), in which we highlighted the purine metabolism, glycolytic process, adenosine triphosphate binding and bone development. These results strongly contribute to the knowledge of the biological mechanisms involved in meat FA profile of Nelore cattle. 相似文献
30.
Pantu Kumar Roy Ahmad Yar Qamar Xun Fang Ghangyong Kim Seonggyu Bang Mahanama De Zoysa Sang Tae Shin Jongki Cho 《Reproduction in domestic animals》2021,56(2):342-350
Oxidative stress is inevitable as it is derived from the handling, culturing, inherent metabolic activities and medium supplementation of embryos. This study was performed to investigate the protective effect of chitosan nanoparticles (CNPs) on oxidative damage in porcine oocytes. For this purpose, cumulus–oocyte complexes (COCs) derived from porcine slaughterhouse ovaries were exposed to different concentrations of CNPs (0, 10, 25 and 50 µg/ml) during in vitro maturation (IVM). Oocytes treated with 25 µg/ml CNPs showed significantly higher levels of GSH, along with a significant reduction in ROS levels compared to control, CNPs10 and CNPs50 groups. In parthenogenetic embryo production, the maturation rate was significantly higher in the CNPs25 group than that in the control and all other treated groups. In addition, when compared to the CNPs50 and control groups, CNPs25-treated oocytes showed significantly higher cleavage and blastocyst development rates. The highest concentration of CNPs reduced the total cell number and ratio of ICM: TE cells in parthenogenetic embryos, suggesting that there is a threshold where benefits are lost if exceeded. In cloned embryos, the CNPs25 group, as compared to all other treated groups, showed significantly higher maturation and cleavage rates. Furthermore, the blastocyst development rate in the CNPs25-treated group was significantly higher than that in the CNPs50-treated group, as was the total cell number. Moreover, we found that cloned embryos derived from the CNPs25-treated group showed significantly higher expression levels of Pou5f1, Dppa2, and Ndp52il genes, compared with those of the control and other treated groups. Our results demonstrated that 25 µg/ml CNPs treatment during IVM improves the developmental competence of porcine oocytes by reducing oxidative stress. 相似文献