A model for long-term sampling of lymph from the jejunal lymphatic trunk in pigs and sheep

Eine Methode zur langfristigen Lymphsammlung aus der jejunalen Lymphbahn bei Schweinen und Schafen Es wird eine Methode zur langfristigen Lymphsammlung im Dünndarmbereich von Schweinen und Schafen vorgestellt. Mit Hilfe eines chirurgischen Eingriffs wurde ein Silikon-Katheder im truncus lymphaticus jejunalis implantiert. Zusätzlich wurde ein zweiter Katheter in die hintere vena cava in Richtung Herz eingesetzt. Beide Katheter wurden sofort miteinander verbunden, um die Wiedereinführung der jejunalen Lymphe in den Blutkreislauf zu gewährleisten. Der negative Druck in der hinteren vena cava im Thoraxteil förderte den Lymphfluß durch das Katheter im truncus lymphaticus jejunalis. Der preprandiale Lymphfluß des Jéjunums betrug bei Schweinen 0,3 ml/h/kg Körpergewicht und stieg postprandial auf 0,78 ml/h/kg an. Beim Schaf betrug der Basiswert 0,75 ml/h/kg. Er stieg nach intraduodenaler Infusion von Rapsöl auf 4,75 ml/h/kg. Eine mechanische Stimulation der intestinalen Receptoren durch 0,9% NaCl-Lösung stimulierte ebenfalls den Lymphfluß.     

Managing the lactating sow for optimal weaning and rebreeding performance.

Management of the lactating sow influences milk production and subsequent reproduction through changes in nutrient intake. The management goal during lactation is to maximize feed intake. Decreasing the effective environmental temperature, increasing the nutrient density of the lactation diet, maintaining fresh adequate supplies of feed and water, and preventing excess weight gain during the prior gestation period will increase nutrient intake during lactation. Effective environmental temperature of the lactating sow can be maintained in the thermoneutral zone by using drip cooling, increased ventilation rates and flooring materials with superior conductive properties. Sow parity, genetics, litter size, and disease level will also influence feed intake. Management practices must account for these factors and, thus, should be tailored to individual farm situations to ensure adequate nutrient intake and prevent aberrations in subsequent reproductive performance.     

Cortisol and corticosterone plasma levels in different Psittaciformes]

Plasma cortisol and corticosterone levels were measured in macaws, African Grey Parrots, Amazon Parrots and budgerigars using a RIA after preliminary cleaning. As in other avian species, the plasma contains predominantly corticosterone.     

Estradiol-17beta in the blood of boars with disorders of sexual potency

The levels of oestradiol-17 beta (E2) in the blood plasma were evaluated in 15 boars exhibiting signs of sexual potency disorders and in 20 boars with no such disorders before and after i. v. administration of chorion gonadotropin (HCG). No significant difference (P greater than 0.05) was found in the E2 levels in the blood plasma of the boars of the two groups before HCG administration. Two hours after the i. v. injection of 500 I. U. of HCG, an insignificant increase in the basal levels of E2 was recorded, reaching on the average 28.9% in the boars with potency disorders and 38.8% in those with no potency changes. Neither were there any significant differences in the E2 levels determined after HCG treatment between the boars with and without sexual potency disorders. It is inferred from the results that deviations in E2 concentration in the blood obviously do not contribute significantly to disorders in the sexual potency of boars.     

Differences in Wheat Cultivar Response to N Supply. I: Differences in Grain Yield Formation

Two-year field trials with winter wheat cultivars Batis and Toronto were conducted in Southern Bavaria, Germany, to investigate the possible causes of cultivar differences in response to N supply varying in total amount and time of application. Cultivar-related differences in grain yields were observed in treatments with low and medium N supply. High doses of N supply resulted in grain yield adjustment or grain yield advantage for cv. Toronto. The results of this study revealed a consistent, genotypic pattern in response to N fertilization in spite of strong seasonal effects. Systematic modifications in canopy growth rates in response to N supply were of particular relevance and a main factor for differences in tillering intensity resulting in modified stand densities. In the present study, cultivar differences in spike development and interactions with N supply related more to abortion than to initiation processes for number of spikelets and number of flowers per spikelet. High grain density (grains per m²) of cv. Toronto was evident during reproduction stages even under conditions of medium N supply. However, decreased growth rates during the later part of grain filling in combination with low 1000 grain weight, which was barely modified by N fertilization, allowed only partial utilization of this potential. It is assumed that sink limitations were of particular relevance for grain yield development in cv. Toronto, while cv. Batis combined a less intense response to N supply with more stability in the development of grain yield components.     

Relationship between blood iron parameters and trichinellosis in swine

Reduced levels of total iron binding capacity and unsaturated iron binding capacity were observed in the blood of trichinous and iron-injected trichinous pigs. No change was observed in their serum iron and saturation concentration levels. Also, reduced iron concentration levels were observed in the livers of trichinous pigs, while increased iron concentration levels were observed in the spleens of trichinous pigs and the livers and spleens of iron-injected pigs. No difference was found with regard to weight gains, number of larvae per gram of tissues, or histologic characteristics of 'nurse cells'.     

Effects of Carbon Dioxide Exposure on Intensively Cultured Rainbow Trout Oncorhynchus mykiss: Physiological Responses and Fillet Attributes

Rainbow trout Oncorhynchus mykiss (261.6 × 24.7 g initial weight, mean × SEM) at 13.1 × 0.2 C were exposed for 94 d to one of three CO₂ treatments: control (22.1 × 2.8 mg/L), medium (34.5 × 3.8 mg/L), or high (48.7 × 4.4 mg/L). Trout were checked daily for survival, and fish were sampled at 0, 28, 56, and 84 d for physiological responses, growth, and fillet quality assessments. Trout were also challenged to a 15-min crowding stress at 93 d to assess their ability to initiate a stress response during hypercapnia. Chronically exposed trout showed nearly 100% survival through 84 d exposure (1 of 1,500 fish died). Growth and physiological results showed that increasing elevated CO₂, concentrations result in corresponding decreased growth rates and CO₂specific physiological parameters: The medium and high CO₂ treatments had significantly slower growth and subsequently smaller fish by 84 d. Exposed trout also showed significantly ( P < 0.05) decreased plasma chloride for medium and high CO₂ treatments compared to the control from 28 through 84 d. Decreased growth and smaller fish in the medium and high CO₂ treatments resulted in correspondingly smaller fresh and smoked fillet weights. Chronic CO₂ exposure did not result in notable changes in ultimate muscle pH. Exposure to 15-min crowding stress at 93 d resulted in significant changes in hematocrit, plasma cortisoI, glucose, and chloride for all treatment groups. CO₂-specific changes were detected in hematocrit, plasma cortisoI, and plasma chloride responses following the 15-min crowding stress.     

Patterns of silver eel (Anguilla anguilla L.) sex ratio in a catchment

Abstract –  Changes in the numbers and size-class structure of European silver eels, Anguilla anguilla , in the River Frémur (France) were examined over a 9-year period after installation of downstream eel passes. The number of silver eels migrating downstream peaked in 1999, then decreased strongly and steadily after 2000, reaching relatively low levels. At the same time, a gradual shift in the silver eel sex ratio from a dominance of males (size from 270 to 442 mm, age from 3 to 6 years) to females (size from 366 to 1112 mm, age from 4 to 9 years) was recorded. Possible explanations for the escapement patterns observed are environmental sex determination and the installation of eel passes on the main hydraulic engineering structures in 1992 and 1996.     

A blind test of the serological response of dogs to infection with Taenia ovis

Fifty six dogs of mixed age and sex were acquired from farms in the Otago/Southland region, and maintained at the Hydatid Research Unit, Taieri, where 43 were each fed two Tueniu ovis cysts. All were bled fortnightly for six or 12 weeks. Coded sera were sent to Wallaceville Animal Research Centre for testing using ELISA, with antigen from T. ovis scoleces. Dog treatments were identified after all tests were complete. A discriminant level was derived from the mean absorbance value plus three standard deviations of 56 sera taken at time zero and 78 sera from serially bled uninfected dogs. None of these 134 sera registered as a false positive using this discriminant level. The data showed no significant deviation from normality, and the expected frequency of the occurrence of false positives is therefore less than 0.14%. Four weeks after infection 63% of dogs proved to be infected were serologically positive, rising to 78% after 6 weeks. When worms were removed by anthelmintic treatment, ELISA absorbance levels decreased. Four weeks after removal 70% of previously infected dogs remained positive, decreasing to 30% after 6 weeks. Six weeks after infection the sensitivity of the test was 78%, and the specificity 63%. However, if dogs with positive ELISA absorbance levels, but which did not purge worms, were regarded as having had worms, the respective figures would be 82% and 100%. The latter figures are similar to our previously published laboratory results. The test is of comparable efficiency to arecoline purgation for surveillance, and has the additional advantage of detecting infection in the majority of those dogs that have been infected for three weeks or more but fail to pass worms on purgation, and a substantial proportion of those infected dogs that were treated by their owners prior to presenting them for purgation in order to avoid detection of infection.