Influence of antibiotics on growth dynamics and movement ability of Salmonella rods

Variety of traits important in diagnostics and epidemiology of pathogenic microorganisms may change due to antibiotics. Movement ability, that is characteristic for every serovar except from Salmonella Gallinarum-Pullorum, is important to salmonellas. In own experiments using semi-fluid MSRV medium, it was found that a decrease in salmonella sensibility to selected antibiotics and chemiotherapeutics due to passage might lead to weakening of its movement ability. Movement ability of all strains (S. Enteritidis, S. Dublin, S. Typhimurium) after passage with amoxycillin, neomycin, colistin and enrofloxacin became weakened as compared to results achieved before passage. The strongest inhibition of movement ability was most often observed in strains after passage on medium with colistin. It seems to be associated with the action mechanism of the antibiotic. Colistin injuries cellular membranes, where flagella (active motoric organ of Salmonella) are anchored. Appearance of drug-resistance as a result of passage at the presence of antibiotics may cause variability of biochemical properties of Salmonella rods and leads to weakening of movement ability of ciliated Salmonella.     

The distribution and chemical coding of neurons in the celiac-superior mesenteric ganglion complex supplying the normal and inflamed ileum in the pig

The present study investigated the chemical coding of neurons in the celiac-superior mesenteric ganglion complex supplying the normal (n=4) and inflamed (n=4) ileum (chemically-induced inflammation) in juvenile pigs using retrograde tracing combined with immunohistochemistry. Ileum-projecting neurons (IPN) were predominantly distributed in the left and right superior mesenteric pools of the ganglion. The majority of them were adrenergic (tyrosine hydroxylase-positive) and also contained neuropeptide Y, somatostatin or galanin. No clear-cut differences in the distribution and chemical coding of IPN were found between normal and inflamed pigs. However, in the inflamed group, the density of peptidergic, IPN-associated nerve fibres was higher than that found in the control group.     

Behavioural analysis of the efficacy of treatments for injuries to the spinal cord in animals

There have been very few clinical trials evaluating therapies for naturally occurring spinal cord injury in dogs and cats. This review describes the methods suitable for evaluating the behavioural recovery of animals with spinal cord injuries, in either a clinical or a laboratory setting. A list of commonly used methods for evaluating behavioural recovery in animals is provided, both in the clinical and laboratory setting; the tests, their limitations and benefits and specific recommendations for their use are also discussed in more depth.     

Biomechanical aspects of the claw-floor interaction in dairy cattle: implications for locomotion and claw disorders

The prevalence of claw disorders is still high among cows housed on concrete floors. Concrete floors affect the locomotion of cattle, their natural behavior. Although many factors affect the development of claw disorders and locomotor problems, biomechanical aspects have hardly been analysed. In this thesis, mechanical (over)loading of the claw and its significance for claw disorders and lameness are discussed. The mechanical characteristics a floor needs to provide in order to enable unrestrained locomotory behavior. This biomechanical approach, which is a relatively new approach in cattle locomotion, has provided new insights. Despite preventive trimming, the weakest parts of the claw capsule are loaded relatively the most. Concrete floors provide too little friction to enable unrestricted cattle locomotion.     

家禽生产中应用喷雾干燥血浆粉

前言喷雾干燥动物血浆粉系从政府检验的屠宰场采集的牛血或猪血,经精心汇集、加工并喷雾干燥而得的产品。喷雾干燥血浆粉有粉状和颗粒状两种。由于采集和加工喷雾干燥血浆粉时所用的方法,其产品成为一种具有多种功能性成分的混合物,其中含有免疫球蛋白、白蛋白、纤维蛋白原、脂类、生长因子、生物活性肽(防卫素、转铁蛋白)、酶以及一些其它因子而这些因子在肠道内具有独立于其营养价值之外的生物活性。这些功能性蛋白质能够提高动物的存活率、健康水平和生产性能。已有人提出了喷雾干燥血浆粉的几种作用模式。总体说来,从提出的这些作用模式…     

Laryngeal collapse in seven brachycephalic puppies

OBJECTIVES: To document the histories, clinical findings, and management of seven puppies with laryngeal collapse occurring secondarily to brachycephalic airway syndrome. METHODS: Seven brachycephalic puppies aged between 4.5 and six months underwent surgery for management of brachycephalic airway syndrome following presentation for exercise intolerance and increased respiratory noise and effort. RESULTS: Stenotic nares of varying severity and an elongated soft palate were common to all dogs. All dogs had tracheal hypoplasia and this was severe in four dogs. Laryngeal collapse was present in all dogs. Two dogs had stage I, four dogs stage II, and one dog stage III laryngeal collapse. The dog with stage III laryngeal collapse and one dog with stage II laryngeal collapse died. There was no apparent association between the changes evident on thoracic radiographs or the degree of tracheal hypoplasia and postoperative outcome. CLINICAL SIGNIFICANCE: The development of severe secondary laryngeal changes in dogs aged six months or less supports the suggestion that immature brachycephalic dogs should undergo assessment and, if indicated, surgery as soon as any clinical signs of BAS are apparent.     

Effects of level of feed intake and Fusarium toxin-contaminated wheat on rumen fermentation as well as on blood and milk parameters in cows

The aims of this study were to examine the effects of and possible interactions between dry matter (DM) intake and feeding Fusarium toxin-contaminated wheat on ruminal fermentation, serum chemical parameters and milk yield of dairy cows. Fourteen dairy cows equipped with ruminal and duodenal cannulas were analysed. All animals were fed the same ration, the daily feed amounts being adjusted to current performance. On DM basis, the ration consisted of 60% concentrate including 55% wheat [Fusarium-contaminated wheat (mycotoxin period) or control wheat (control period)] and was completed with 40% maize and grass silage. Each cow was fed the contaminated wheat [deoxynivalenol (DON), 8.21 mg/kg DM and zearalenone (ZON), 0.09 mg/kg DM] and the control wheat (0.25 mg DON/kg DM and 51 microg ZON/kg DM). As expected, a higher organic matter (OM) intake decreased the amounts of fermented crude nutrients related to the respective intakes. An increased amount of crude protein degraded (p < 0.05) and a lower molar percentage of propionate in the rumen fluid were observed when feeding the Fusarium toxin-contaminated wheat at increased OM intakes in comparison with the control wheat. The activities of serum aspartate aminotransferase (ASAT; p < 0.001), glutamate dehydrogenase (GLDH; p < 0.01) and gamma glutamyl transferase (gamma-GT; p < 0.01) increased with increasing OM intake and were not related to the mycotoxin contamination of the wheat.     

Immunohistochemical localization of distinct angiotensin II AT1 receptor isoforms in the kidneys of the Sprague-Dawley rat and the desert rodent Meriones crassus

Employing a purified lgG fraction of a polyclonal anti-AT1 receptor anti-body, raised against a synthetic octapeptide encompassing residues 14-21 of the first extracellular domain of the AT1 polypeptide, selective AT1 receptor expression was immunohistochemically demonstrable within renal structures in Sprague-Dawley (SD) rats and the desert rodent Meriones crassus. In both animal models, prominent AT1 receptor labelling was evident in renal vascular elements, particularly cortical inter-lobular arteries (IA) as well as vasa recta bundles in the inner stripe of the outer medulla. Less intense labelling was observed among peritubular capillary endothelia within the deep cortex, and at both the outer stripe and the inter-bundle regions of the inner stripe of the outer medulla. The binding of the anti-peptide anti-body was, however, lacking among glomeruli and, except for the intense labelling confined to basement membranes of Bowman's capsule of deep nephrons, was virtually absent in all renal tubular structures of both animal models. Structural assessment of the expressed AT1 receptors by two-dimensional Western blotting revealed that a spectrum of structurally distinct AT1 receptor isoforms is expressed in the renal tissues of both animal models. This spectrum was constituted by isoforms of equal size (70 kDa) but distinct pls in SD rats, and of both different sizes (67-73 kDa) and isoelectric points in M. crassus. In either species, the charge and/or size heterogeneity of AT1 receptor isoforms may be attributed in part to differential post-translational glycosylation mechanisms of the AT1 receptor polypeptide backbone. The potential for the differential glycosylation state of AT1 receptors to alter recognition properties may add another level of complexity to tissue-specific and/or species-specific mechanisms underlying angiotensin II interactions in the kidney.     

Journey length and high temperatures: effects on rabbit welfare and meat quality

The transport of domestic animals by road can increase levels of stress and decrease meat quality, especially in unfavourable climates. The purpose of this study was to investigate the effect of journey duration and vertical position on the transport truck on some physiological indicators of stress and on instrumental meat quality parameters in commercial rabbits. In the summer months (June and July, 2003), 78 rabbits were subjected to either long (7 h) (LJ) or short (1 h) (SJ) journeys (3 replicates each, n = 6) between the farm and an abattoir in northern Spain. The position (top, middle, or bottom) occupied by the rabbits on the Multi-Floor cage Rolling Stand (MFRS) of the transport truck was recorded. Blood samples were collected at sticking and meat pH was measured at 24 h post-mortem (pH24). At 48 h post-mortem, samples of the M. longissimus dorsi were used to determine water-holding capacity (WHC) and instrumental tenderness using an INSTRON machine. The levels of corticosterone, glucose, lactate, and creatine kinase were slightly higher in LJ than in SJ samples, but the difference was not statistically significant (p < or = 0.10). Independent of journey length, rabbits in the middle and bottom of the MFRS showed higher levels (p < or = 0.05) of glucose and creatine kinase (middle), and corticosterone (bottom) than the rabbits located at the top floor. The pH 24 and WHC values of the SJ and LJ rabbits did not differ significantly. Journey length had a significant effect (p < or = 0.01) on meat tenderness. The meat from rabbits subjected to LJ had higher values of maximum stress and total toughness than did the SJ rabbits (p < or = 0.05). There were similar differences (p < or = 0.05) between LJ and SJ rabbits in their stress values of compression at 20% and 40% (measures of the tenderness of raw meat). In hot weather, the position on the transport truck appeared to have a greater effect on rabbit welfare than the duration of the journey.