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991.
van der Peet-Schwering CM Kemp B Binnendijk GP den Hartog LA Spoolder HA Verstegen MW 《Journal of animal science》2003,81(9):2247-2258
The effect of feeding sows a starch diet or a diet with a high level of nonstarch polysaccharides (NSP) during gestation, lactation, or both gestation and lactation during the first three parities on reproductive performance, body weight, and backfat was studied. Four-hundred and forty-four postpuberal gilts were allotted to a 2 x 2 x 2 factorial experiment. Treatments were diet composition during gestation (including the weaning-to-estrus interval; G-Starch: 274 g/kg of starch and 123 g/kg of fermentable NSP or G-NSP: 86 g/kg of starch and 300 g/kg of fermentable NSP), diet composition during lactation (L-Starch: 293 g/kg of starch and 113 g/kg of fermentable NSP or L-NSP: 189 g/kg of starch and 216 g/kg of fermentable NSP) and group-housing system during gestation (free access stalls or electronic feeding). Both gestation diets were formulated to be isoenergetic. During lactation, sows were given free access to the lactation diets from d 6 after parturition onwards. Body weight and backfat gains during gestation were lower in sows fed the G-NSP diet than in those fed the G-starch diet (P < 0.001). The effects were more pronounced in the electronic feeding system than in the free access stalls. These results indicate an overestimation of the energy value of fermentable NSP. Body weight and backfat losses during lactation were less in sows fed the G-NSP diet during gestation than in those fed the G-starch diet (P < 0.05),which can be explained by a 0.4 kg/d higher (P < 0.001) feed intake during lactation of the sows fed the G-NSP diet. Sows fed the L-NSP diet lost more backfat during lactation than sows fed the L-starch diet (P < 0.05). The number of total piglets born and live-born piglets was 0.5 piglet higher in sows fed the G-NSP diet than in those fed the G-starch diet (P < 0.05). Lactation diet did not affect the number of total piglets born or live-born piglets. This study shows that, although high NSP diets negatively influence body weight and backfat thickness of the sows, it is possible to feed sows a diet with a high level of fermentable NSP diet during both gestation and lactation without negative effects on reproductive performance. Under the conditions of this study, feeding sows a diet with a high level of fermentable NSP during gestation and a high level of starch during lactation seems the most favorable feeding strategy. 相似文献
992.
In a 2 X 2 factorial study, a broiler starter ration was amended for vitamin A (control, C; deficient, A) and probiotic status (-, P) to investigate their modulatory effects onthe host immune system. Birds were inoculated orally with Eimeria acervulina (EA) oocysts, and disease susceptibility was evaluated by assessment of fecal oocyst shedding. Humoral and local cellular mediated immunity were assessed by evaluation of antibody and cytokine (interferon-gamma [IFN-gamma] and interleukin-2 [IL-2]) levels in sera and intestinal secretions on a 3-day interval after inoculation. Fecal oocyst shedding was highest (P < 0.05) in A- birds, followed by AP, C-, and CP birds. Feeding the probiotic reduced shed oocysts by 20% in A fed birds and by 26% in C fed birds. Intestinal IFN-gamma was relatively constant in all treatment groups except for A-, where it declined steadily and was lower (P < 0.05) from day 6 on. Serum IFN-gamma levels fluctuated within each treatment and over time were not revealing. Intestinal IL-2 was highest in CP birds at 3 and 9 days postinfection (DPI) and lowest in A- birds at 3, 9, and 12 DPI (P < 0.05); no difference between treatments was found at 6 DPI (P > 0.05). Eimeria-specific intestinal antibody (Ab) level was constant (P > 0.05) in C- birds but increased with time (P < 0.05) in A-, AP, and CP birds. Serum Ab levels were also constant in A- and CP birds but increased (P < 0.05) in C- and AP birds after 6 DPI. The data demonstrate for the first time a probiotic-enhanced immunity in vitamin A deficient birds. This study is also the first to demonstrate the probiotic effect on local cell-mediated immunity of chickens, best manifested by apparent lower intestinal invasion and development by EA, on the basis of higher IL-2 secretion and lower EA oocyst production. 相似文献
993.
994.
Alonso-Villalobos P Martinez-Grueiro MM 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2000,47(1):1-8
The secretion of acetylcholinesterase (AChE) by female and male Heligmosomoides polygyrus was studied in different in vitro culture media. AChE secretion was increased in the presence of fetal calf serum or bovine serum albumin (BSA). In the absence of crowding effects, specific AChE activity in excretion/secretion products was higher for male (2.41 +/- 0.07 mumol min-1 l-1 mg-1) than for female (0.56 +/- 0.04 mumol min-1 mg-1) worms but on a per nematode basis both sexes showed comparable rates of secretion. Acetylthiocholine iodide was the favoured substrate of the enzyme. When the nematodes were incubated in vitro with albendazole (ABZ), ricobendazole (RBZ), mebendazole (MBZ), levamisole (LVM), morantel (MRT) or ivermectin (IVM), at concentrations from 1 mM to 10 nM, in RPMI medium for 2 or 6 h and then transferred to a drug-free medium (RPMI medium supplemented with 0.5% BSA) for 24 h or continuously exposed to the drugs in supplement-free medium (24 h), the concentration- and time-dependent inhibitory effects on AChE secretion were observed. The continued exposure to the drugs for all incubation periods (with a single exception for LVM 1 mM) produced the highest levels of inhibition. Under these conditions, the concentrations inhibiting the secretion of AChE by 50% (IC50) relative to drug-free controls were estimated. The IC50 values ranged from 0.012 microM (IVM) to 2.96 microM (MRT). The potential of this bioassay for the selective primary evaluation of new compounds with broad-spectrum anti-nematodal activity is discussed. 相似文献
995.
996.
An Abyssinian cat examined because of hypoproteinemia and weight loss was found to have epitheliotropic T-cell lymphosarcoma of the gastrointestinal tract. Neoplastic lymphocytes infiltrated the epithelium and lamina propria of the stomach, small intestine, and large intestine. Metastatic foci were found in the lungs and the musculature of the right hind limb. Chemotherapy resulted in transient shrinkage of the lung and limb masses; however, these masses grew to approximately their original size within 2 weeks after initiation of treatment, and the cat was euthanatized. 相似文献
997.
998.
A. Pratelli A. Cavalli G. Normanno M.G. De Palma G. Pastorelli V. Martella C. Buonavoglia 《Zoonoses and public health》2000,47(4):273-276
The results of vaccination trials carried out on pups with maternally derived antibodies (MDA) to canine parvovirus (CPV), using a modified‐live CPV‐2b variant vaccine (29‐97/40 strain), are reported. The vaccine was able to overcome the obstacle of MDA, and to elicit protective immunity in 100% of the pups whose antibody titres were 1:10–1:40, 83% of the pups with titres of 1:80, 57% of the pups with titres of 1:160, and even in 60% of the pups with antibody titres of 1:320. 相似文献
999.
Sánchez Ramos O González Pose A Gómez-Puerta S Noda Gomez J Vega Redondo A Águila Benites JC Suárez Amarán L Parra NC Toledo Alonso JR 《Comparative immunology, microbiology and infectious diseases》2011,34(3):259-265
Recombinant adenoviral vectors have emerged as an attractive system for veterinary vaccines development. However, for poultry vaccination a very important criterion for an ideal vaccine is its low cost. The objective of this study was to test the ability of chicken CD154 to enhance the immunogenicity of an adenoviral vector-based vaccine against avian influenza virus in order to reduce the amount of antigen required to induce an effective immune response in avian. Chickens were vaccinated with three different doses of adenoviral vectors encoding either HA (AdHA), or HA fused to extracellular domain chicken's CD154 (AdHACD). Hemagglutination inhibition (HI) assay and relative quantification of IFN-γ showed that the adenoviral vector encoding for the chimeric antigen is able to elicit an improved humoral and cellular immune response, which demonstrated that CD154 can be used as a molecular adjuvant allowing to reduce in about 50-fold the amount of adenoviral vector vaccine required to induce an effective immune response. 相似文献
1000.
A.L. Soraci D.S. Perez G. Martinez S. Dieguez M.O. Tapia F. Amanto R. Harkes O. Romano 《Research in veterinary science》2011,90(3):498-502
Disodium-fosfomycin pharmacokinetics has been studied in different species after oral, intravenous, intramuscular and subcutaneous administration. At present there are neither documented clinical experiences of the use of fosfomycin in pigs nor any published studies in weaning piglets, although it is a period of high incidence of infectious diseases. The pharmacokinetics and the bioavailability of sodium fosfomycin were studied in post weaning piglets after intravenous and intramuscular administration of 15 mg/kg of body weight. Plasma concentrations were measured by a high-performance liquid ms/ms. After IV administration the area under the fosfomycin concentration:time curve in plasma was AUC(0–12) of 120.00 ± 23.12 μg h/ml and the volume of distribution (Vd) of 273.00 ± 40.70 ml/kg. The elimination was rapid with a plasma clearance of 131.50 ± 30.07 ml/kg/h and a T1/2 of 1.54 ± 0.40 h. Peak serum concentration (Cmax), Tmax, AUC(0–12) and bioavailability for the IM administration were 43.00 ± 4.10 μg/ml, 0.75 ± 0.00 h, 99.00 ± 0.70 μg h/ml and 85.5 ± 9.90% respectively. Different authors have determined a minimum inhibitory concentration (MIC90) ranging from 0.25 μg/ml for Streptococcus sp. and 0.5 μg/ml for Escherichia coli. Considering the above, and according to the values of plasma concentration vs time profiles observed in this study, effective plasma concentrations of fosfomycin for sensitive bacteria can be obtained following IV and IM administration of 15 mg/kg in piglets. 相似文献