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31.
32.
C.M. Westermann L. Dorland M.G.M. de Sain-van der Velden A. Barneveld H.A. Keizer 《Research in veterinary science》2011,91(1):144-149
The objective of this study is to assess the influence of acute exercise, training and intensified training on the plasma amino acid profile.In a 32-week longitudinal study using 10 Standardbred horses, training was divided into four phases, including a phase of intensified training for five horses. At the end of each phase, a standardized exercise test, SET, was performed. Plasma amino acid concentrations before and after each SET were measured.Training significantly reduced mean plasma aspartic acid concentration, whereas exercise significantly increased the plasma concentrations of alanine, taurine, methionine, leucine, tyrosine and phenylalanine and reduced the plasma concentrations of glycine, ornithine, glutamine, citrulline and serine. Normally and intensified trained horses differed not significantly. It is concluded that amino acids should not be regarded as limiting training performance in Standardbreds except for aspartic acid which is the most likely candidate for supplementation. 相似文献
33.
S. Gde J. Bennewitz K. Kirchner H. Looft P.W. Knap G. Thaller E. Kalm 《Livestock Science》2008,114(1):31-41
Data from 32 nucleus and multiplier herds in Germany was used to estimate variance components and breeding values for five maternal behaviour traits in sows. The estimation was performed univariately using an animal threshold model. About 31,000 farrowings recorded from December 2003 until July 2005 were included. The heritability coefficients were 0.07 (0.06) for group behaviour, 0.06 (0.03) for attitude to people, 0.05 (0.01) for maternal ability, 0.03 (0.01) for crushing of piglets and 0.02 (0.02) for savaging of piglets. Additionally, genetic correlations between the behaviour traits and between the behaviour traits and litter size, respectively, were estimated multivariately by REML with a linear model. Low heritability and weak genetic correlation to litter size at birth indicate that it may be difficult to genetically improve the maternal behaviour, and that selection for better mothering ability is not necessarily accompanied by reduced litter size at birth. 相似文献
34.
Peters JW de Boer B Broeze-ten Voorde G Broeze J Wiemer P Sterk T Spoormakers T 《Tijdschrift voor diergeneeskunde》2008,133(7):272-278
Prevalence of dental disorders in 483 horses and ponies Five equine veterinarians working at three equine referral hospitals examined the oral cavity of 483 horses and ponies prior to surgery, to gain information about the prevalence of common dental disorders in the horse. A thorough examination, using hands/fingers, a full-mouth speculum, a dental mirror and a good light source, is essential to detect such disorders. Many horses examined needed dental attention even though there were no problems with mastication or riding. The most detected abnormalities were sharp enamel points on the buccal side of the upper arcade and the lingual side of the lower arcade, and hooks at 106/206 and 311/411. Regular dental care would improve the condition and welfare of horses. 相似文献
35.
Derossi R Medeiros U de Almeida RG Righetto FR Frazílio FO 《Veterinary journal (London, England : 1997)》2008,178(2):294-297
The aim of the study was to evaluate and compare the effects of caudal epidural administration of meperidine (MP), lidocaine (LD), and a combination of the two (MPLD) in six mature saddle horses. Horses were randomly assigned to receive three treatments (MP 0.3 mg/kg; LD 0.2 mg/kg; and MPLD: MP 0.3 mg/kg and LD 0.2 mg/kg), with at least 1 week between treatments. Drugs were injected into the epidural space between the first and second coccygeal areas in conscious standing horses. Analgesia, ataxia, sedation, cardiovascular and respiratory effects, and rectal temperature were recorded at different intervals before (baseline) and after administration. Epidural administration of MPLD resulted in a longer duration of analgesia of the tail, perineum, and upper hind limb regions than did administration of MP or LD alone. 相似文献
36.
Summary A standardized test was developed to compare the efficacy of Aujeszky's disease virus (ADV) vaccines under laboratory conditions. Per test 3 groups of 6 to 8 sero‐negative pigs were used. The first vaccination was done at 10 weeks of age. One group was vaccinated once, another was vaccinated twice and the 3rd served as control. Pigs were challenge exposed to the virulent NIA‐3 strain of ADV 12 weeks after the first vaccination. Apart from mortality, average periods of growth arrest, fever and virus shedding after challenge were used as parameters to evaluate vaccine efficacy. Two inactivated and 4 attenuated vaccines were tested. Two attenuated vaccine viruses were excreted after vaccination. Despite maximal standardization, a considerable variation still existed between the experiments in mortality and growth arrest periods of control pigs after challenge. However, the controls were always more severely affected than the vaccinated pigs. All vaccines except one were effective in preventing death after challenge, but none conferred complete protection. Most vaccinated pigs still lost weight, developed fever and shed virus after challenge. Revaccination after 3 or 4 weeks had little effect, particularly with the attenuated vaccines. The results of the present study indicate that 2 of the attenuated vaccines conferred the best protection, I attenuated vaccine appeared to be as effective as the 2 inactivated ones, and the 4th attenuated vaccine was least effective. 相似文献
37.
38.
Ribbens S Dewulf J Koenen F Mintiens K de Kruif A Maes D 《Preventive veterinary medicine》2009,88(1):57-66
Knowledge of the frequency of direct and indirect contacts between pig herds is a requirement for understanding the potential between-herd transmission of pathogens. Our aim was to investigate the different contacts between Belgian pig herds. We obtained data by conducting a postal survey on 421 pig herds in August 2005 and by analysis of available information on livestock movements in the national identification-and-registration database (18-months period in 2004-2006). Direct contacts included transports of pigs by onto-farm, off-farm and between-farm movements. Indirect contacts included vehicles entering the herd and visitors entering the stables. The median number of direct contacts per herd made by onto-farm movements was 0.2/month (Q1: 0; Q3: 0.5). About 1.2% of herds had > or = 3 onto-farm movements/month. We used a zero-inflated negative-binomial regression model to describe differences in the number of onto-farm movements according to herd size and herd type. Piglet multipliers followed by finishing herds were predicted to have the most onto-farm movements. Farrow-to-finishing herds made less movements compared to breeding herds. A median of 3997 between-farm movements/month was made in Belgium; these mainly concerned piglets. The median number of origin herds during an 8-month period for between-farm movements was 4 (Q1: 2; Q3: 8). For a typical 1-month period, we constructed directed graphs of between-farm piglet and replacement stock movements, illustrating potential receivers and distributors of infection. Of these between-farm movements, many were made over a short distance (median straight-line distance 19 km (Q1: 8; Q3: 36)). The median number of vehicles entering a herd and visitors entering the stables was 8/month (Q1: 6; Q3: 13) and 3/month (Q1: 2; Q3: 6) respectively. The number of indirect contacts by vehicles and persons were associated with herd size (Spearman's r: 0.7 and 0.2), herd type and other factors. Skewness of both direct and indirect contacts, illustrated that there was a wide variety in contact structure between pig herds in Belgium. Infection control might benefit by accounting for this variation in contacts and by targeting 'high-risk' herds in case of animal-disease emergencies. 相似文献
39.
Kovalik M Thoday KL Handel IG Bronsvoort BM Evans H van den Broek AH Mellanby RJ 《Veterinary dermatology》2011,22(2):173-180
The effect of ciclosporin A (CsA) on glucose homeostasis was investigated in 16 dogs with atopic dermatitis by determining plasma glucose, serum fructosamine and insulin concentrations, and serial insulin and glucose concentrations following a glucagon stimulation test, before and 6 weeks after CsA therapy at 5 mg/kg once daily. All dogs completed the study. Following CsA treatment, the median serum fructosamine concentrations were significantly higher (pretreatment 227.5 μmol/L; post-treatment 246.5 μmol/L; P = 0.001; reference range 162-310 μmol/L). Based on analyses of the areas under concentration-time curves (AUC) pre- and post-CsA treatment, plasma glucose concentrations were significantly higher (AUC without baseline correction 31.0 mmol/L/min greater; P = 0.021) and serum insulin concentrations were significantly lower (AUC without baseline correction 217.1 μIU/mL/min lower; P = 0.044) following CsA treatment. Peak glucose concentrations after glucagon stimulation test were significantly higher following CsA treatment (10.75 versus 12.05 mmol/L; P = 0.021), but there was no significant difference in peak serum insulin (52.0 versus 35.0 μIU/mL; P = 0.052). There was a negative correlation between baseline uncorrected insulin AUC and trough serum log CsA concentrations (r = -0.70, P = 0.005). The administration of CsA to dogs with atopic dermatitis leads to disturbances in glucose homeostasis. The clinical significance of this is unclear, but it should be taken into account when considering CsA treatment in dogs that already have such impairments. 相似文献
40.