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991.
992.
Ziaei N Guy JH Edwards SA Blanchard PJ Ward J Feuerstein D 《British poultry science》2008,49(2):195-201
1. The objective of this study was to investigate whether it is possible to reduce phosphorus (P) excretion by feeding a lower level of dietary P than that currently recommended, without compromising welfare, and whether this is sensitive to the level of dietary calcium (Ca). 2. A randomised complete block design was used with a total of 224 1-d-old male chicks of a commercial genotype in two batches. Chicks had a 10-d adaptation period. After this, they were moved to cages and allocated to one of 4 dietary treatments (4 and 3 birds per cage in batch 1 and 2, respectively). A standard level of Ca and P (8.3 and 6.6 g/kg, respectively) was compared with three lower levels of Ca (7.3, 6.3 and 5.3 g/kg) all at the same reduced level of P (5.5 g/kg). Records were made of live weight of birds on an individual basis and feed and water consumption on a cage basis. Every 7 d, the dry matter (DM) content of a sample of mixed excreta from each cage was measured. Birds were slaughtered and samples taken for analysis of plasma mineral content, retention of N, Ca and P and tibia bone strength. 3. The initial reduction in dietary mineral level did not adversely affect performance or bone strength. However, decreasing dietary Ca level below 7.3 g/kg, at constant P, led to reduced feed consumption and bone strength. Dietary treatment had no significant overall effect on water intake, water : feed ratio, excreta DM content, Ca and P retention or metabolisability of DM. There was no significant correlation between mean plasma Ca or P level and DM content of rectal digesta. 4. In conclusion, reducing dietary P from 6.6 to 5.5 g/kg to reduce potential environmental impact of broiler production had an adverse effect on bird welfare when the level of Ca was reduced below 7.3 g/kg, as a result of decreased feed intake in the early growth period and reduced skeletal strength. 相似文献
993.
The objective of this study was to investigate the effect of infusing whole dead semen (WDS) after AI with diluted commercial semen on uterine inflammatory reaction and embryonic survival rate in gilts. Sixty Yorkshire-Landrace gilts were assigned at their second estrus to one of the following AI treatments: 1) commercial semen adjusted to 1 x 10(9) sperm cells (S1) per dose, followed by an infusion of 80 mL of WDS (S1-WDS); 2) S1 followed by an infusion of 80 mL of Beltsville Thawing Solution (S1-BTS); 3) commercial semen adjusted to 3 x 10(9) sperm cells (S3) per dose, followed by an infusion of 80 mL of BTS (S3-BTS); and 4) a negative control group, in which gilts received two infusions of 80 mL of BTS (BTS). Two days after the first AI, eight gilts from Groups 1, 2, and 4 were slaughtered and reproductive tracts were collected. One horn was cut open longitudinally along the antimesometrial aspect and endometrial samples were taken and immediately frozen for analysis of messenger RNA (mRNA) abundance for inflammatory cytokines and growth factors. The other horn was flushed with 20 mL of PBS, and the contents of interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta1 (TGF-beta1) were determined by ELISA. On d 25 after AI, gilts from Groups 1, 2, and 3 were slaughtered and their reproductive tracts were collected to evaluate the number of fetuses and corpora lutea. On d 2 after the first AI, only TGF-beta1 was detected in the flush of all gilts, and no difference was observed between S1-WDS, S1-BTS, and BTS gilts. Endometrial levels of IFN-gamma and interleukin (IL)-6 mRNA were marked in all gilts, but they were not affected by the AI treatments, whereas the mRNA abundances for IL-1 and IL-2 were negligible. Infusions of WDS or BTS after a fertile AI did not affect IGF-I, IGF-I receptor, or IGF-II mRNA levels compared with gilts infused with BTS only, whereas the mRNA abundance for the IGF-II receptor was decreased (P < 0.05) in WDS-infused gilts. In gilts inseminated with S1 doses, infusion of WDS did not affect the number of live embryos. Although infusions of WDS did not affect the mRNA level and secretion of the cytokines measured and did not improve embryonic survival rates, further studies are needed to better understand the influence of semen composition on the uterine response after mating. 相似文献
994.
995.
S Avgeris C D Lothrop T P McDonald 《Journal of the American Veterinary Medical Association》1990,196(6):921-924
Plasma von Willebrand factor antigen concentration was determined in 15 dogs with suspected hypothyroidism, in 1 dog with hyperthyroidism, and in 14 euthyroid dogs. The mean +/- SEM von Willebrand factor:antigen concentration in hypothyroid dogs (47.1% +/- 12.6%) was significantly decreased (P less than 0.0005), compared with that in euthyroid dogs (94.7 +/- 5.6%). Four hypothyroid dogs were given thyroxine for 1 month and all 4 had an increase in von Willebrand factor:antigen concentration. The plasma von Willebrand factor:antigen concentration was 200% in the hyperthyroid dog. Seemingly, reduced concentrations of plasma von Willebrand factor:antigen can be found in dogs in association with congenital von Willebrand disease or with von Willebrand disease acquired through hypothyroidism. 相似文献
996.
Genetic analysis of human and swine influenza A viruses isolated in Northern Italy during 2010–2015 下载免费PDF全文
C. Chiapponi E. Ebranati E. Pariani S. Faccini A. Luppi L. Baioni R. Manfredi V. Carta M. Merenda P. Affanni M. E. Colucci L. Veronesi G. Zehender E. Foni 《Zoonoses and public health》2018,65(1):114-123
Influenza A virus (IAV) infection in swine plays an important role in the ecology of influenza viruses. The emergence of new IAVs comes through different mechanisms, with the genetic reassortment of genes between influenza viruses, also originating from different species, being common. We performed a genetic analysis on 179 IAV isolates from humans (n. 75) and pigs (n. 104) collected in Northern Italy between 2010 and 2015, to monitor the genetic exchange between human and swine IAVs. No cases of human infection with swine strains were noticed, but direct infections of swine with H1N1pdm09 strains were detected. Moreover, we pointed out a continuous circulation of H1N1pdm09 strains in swine populations evidenced by the introduction of internal genes of this subtype. These events contribute to generating new viral variants—possibly endowed with pandemic potential—and emphasize the importance of continuous surveillance at both animal and human level. 相似文献
997.
The objective of this study was to determine the effect of feeding Ascophyllum nodosum (ANOD) to lambs at 0 (control), 0.5, 1, or 2% of DMI/d for 2 wk on lamb physiology in response to forced walking and transport during hot weather. Forty-four lambs (26 kg +/- 4.3) were used, and each lamb swallowed 3 gelatin capsules filled with ANOD or their normal 16% CP, pelleted grain ration twice daily, with the amount of ANOD dependent on the treatment. The amount of ANOD did not affect ear canal temperature or cortisol concentrations during 60 min of forced walking. The range between the minimum and maximum ear canal temperature for each lamb during 12 h of transport was narrower in lambs receiving the 2% ANOD than the control group (P = 0.05), and the 2% ANOD group also had lower (P = 0.05) ear canal temperatures than the control group during hot periods of transport. After 4 (P = 0.09) and 8 h (P = 0.05) of transport, the control group tended to have greater cortisol concentrations than the 2% ANOD group. Many differences among treatments were found in plasma protein, albumin, calcium, phosphorus, glucose, blood urea nitrogen, aspartate aminotransferase, magnesium, sodium, potassium, and chloride concentrations posttransport; mainly, the control and 0.5% ANOD groups had greater (P < 0.05) concentrations than the other 2 treatments. Aldosterone concentrations were greater in the control and 0.5% ANOD group than in the 1 and 2% ANOD groups before transport, whereas the concentrations were not different after transport, suggesting pretransport concentrations were lowered by supplementation. The 1 and 2% ANOD groups lost more BW than the control group as a result of transport (P = 0.04). After transport, no differences were observed in the latency for lambs to drink, eat, or lay. There was a suppression of the IgG and IgM antibody responses at 4 and 7 d after administration of ovalbumin, with greater ANOD supplementation rates suppressing antibody response the greatest. Although ANOD decreased ear canal temperature in hot periods of transport, stabilized electrolyte concentrations, and decreased cortisol throughout transport, it also suppressed the antibody response indicating that the effect of ANOD on immune function merits further investigation. 相似文献
998.
Elizabeth H. Yorke Carter E. Judy Travis C. Saveraid Conor P. McGowan Fred J. Caldwell 《Veterinary radiology & ultrasound》2014,55(1):35-44
Distal border fragments of the navicular bone are increasingly being detected due to the improved capabilities of magnetic resonance imaging (MRI), but their clinical significance remains unclear. The purpose of this retrospective study was to describe the location, size, and frequency of fragments in a cohort of horses presented for MRI of the foot and to compare MRI findings with severity of lameness. Archived MRI studies and medical records were searched from March 2006 to June 2008. Horses were included if a distal border fragment of the navicular bone was visible in MRI scans. Confidence interval comparisons and linear regression analyses were used to test hypotheses that fragments were associated with lameness and lameness severity was positively correlated with fragment volume and biaxial location. A total of 453 horses (874 limbs) were included. Fragments were identified in 60 horses (13.25%) and 90 limbs (10.3%). Fifty percent of the horses had unilateral fragments and 50% had bilateral fragments. Fragments were located at the lateral (62.2%), medial (8.89%), or medial and lateral (28.9%) angles of the distal border of the navicular bone. There was no increased probability of being categorized as lame if a fragment was present. There was no significant difference in fragment volume across lameness severity categorizations. Confidence intervals indicated a slightly increased probability of being classified as lame if both medial and lateral fragments were present. Findings indicated that distal border fragments of the navicular bone in equine MRI studies are unlikely to be related to existing lameness. 相似文献
999.
1000.
Influence of Disease Process and Duration on Acute Phase Proteins in Serum and Peritoneal Fluid of Horses with Colic 下载免费PDF全文
T.H. Pihl E. Scheepers M. Sanz A. Goddard P. Page N. Toft P.H. Andersen S. Jacobsen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(2):651-658