Cryopreservation ofTheileria-infected lymphoblastoid cells with functional assessment of viability

Summary Bovine lymphoblastoid cell cultures infected withTheileria annulata were frozen to −60°C in a programmable cooling apparatus using continuous cooling rates of 1°C/min, 10°C/min and 120°C/min and a two-step cooling rate with an equilibration period of 20 min at −30°C. The cryopreservative was DMSO at concentrations of 5, 10 and 15%. Aliquots of cryopreserved material were stored in the vapour phase of a liquid nitrogen refrigerator and resuscitated by rapid thawing in a 40°C water bath. The efficiency of the freezing methods was compared by assessing the viability and plating efficiency of cells after resuscitation, dilution and equilibration in cell culture medium. A significant correlation was recorded between the results obtained by these two methods which showed that the two-step method yielded cells with viability of 95 to 97% and a plating efficiency equal to that of unfrozen cells. It was concluded that such a freezing method would be ideal for the cryopreservation and storage of banks ofTheileria annulata-infected cells for vaccine purposes.

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Resumen Se congelaron a −60°C cultivos de células linfoblast bovinas infectadas conTheileria annulata. El proceso se llevó a cabo en un aparato enfriador programable, usando tasas de enfriamiento continuo de 1°C/min, 10°C/min y 120°C/min, y una tasa de enfriamiento de dos etapas, con un período de equilibración de 20 minutos a −30°C. El criopreservativo fue DMSO a concentraciones de 5, 10 y 15%. Se guardaron aliquotas del material criopreservado, et la fase vaporosa de un refrigerador de nitrógeno líquido, siendo resucitadas mediante el descongelamiento rápido en ba?o de maría a 40°C. La eficiencia de los métodos de congelamineto, se comparó evaluando la viabilidad y eficiencia de crecimiento en cultivos despues del descongelamiento, la equilibración y dilución en medios para el cultivo celular. Se obtuvo asi, una correlación significativa, entre los resultados provenientes de estos dos métodos, los cuales mostraron que el de dos etapas produjo células con una viabilidad de 95–98% y una eficiencia de crecimiento en cultivos, igual a las de las células sin congelar. Se concluyé, que este método de congelación sería ideal para la criopreservación y almacenamiento en bancos, de células linfoblastoides infectádas conTheileria annulata, para la producción de vacuua.

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Résumé Des cultures de cellules lymphoblasto?des bovines infectées parTheileria annulata ont été congelées à −60°C dans un appareil de congélation programmable, à des vitesses de 1°C/min, 10°C/min et 120°C/min et un rythme en deux temps avec une période d’équilibrage de 20 min à −30°C. Le cryopréservative était DMSO en concentrations de 5, 10 et 15%. Des échantillons aliquotes du matériel cryopréservé ont été conservés dans la phase gazeuse d’un congélateur à azote liquide et réanimés par décongélation rapide dans un bain-marié à 40°C. L’efficacité des méthodes de congélation a été jugée par l’estimation de la viabilité et de l’aptitude à coloniser des cellules après réanimation, dilution et équilibrage dans le milieu de culture cellulaire. On a obtenu une corrélation significative entre les résultats obtenus par les deux méthodes, le rythme en deux temps donnant des cellules dont la viabilité était de 95–97% et l’aptitude à coloniser égale à celle des cellules non congelées. Il a été conclu que cette méthode de congélation était idéale pour la cryopréservation et la conservation des banques de cellules infectées parT. annulata en vue de la préparation de vaccins.

     

Titrimetry as a method of assessment of rumen contents

Titration of rumen fluid reveals the prevailing buffer system: VFA salts and sometimes bicarbonates in the normal state, ammonium salts or lactate in pathological conditions. Titrimetry appears to be a convenient method to study digestion in the rumen.

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Resume La titration du liquide ruminal permet de mettre en évidence le système tampon prédominant: sels d'acides gras volatils, et quelquefois bicarbonates dans les conditions normales, sels d'ammonium ou lactate dans les conditions pathologiques. La titrimétrie paraît être une méthode convenable pour étudier la digestion dans le rumen.

     

Titrimetry as a method of assessment of rumen contents

Titration of rumen fluid reveals the prevailing buffer system: VFA salts and sometimes bicarbonates in the normal state, ammonium salts or lactate in pathological conditions. Titrimetry appears to be a convenient method to study digestion in the rumen.     

Pneumonia disease assessment using a slaughterhouse lung-scoring method

The aims of this study were the evaluation of a quantitative method for the assessment of pneumonia lesions applied to heavy-weight slaughtered pigs, the identification of risk factors connected with the increase in the prevalence and severity of the lesions and the evaluation of a possible correlation between the presence of pneumonia lesions and the decrease in the carcass quality. The lungs of 10 041 pigs (109 slaughtered batches) coming from 91 farms located in Northern Italy were examined. Lung lesions were scored using the method developed by Madec and Kobisch (Journ. Rech. Porc. Fr., 14, 1982, 405). Before the scoring, anamnestic information regarding the farm of origin of each batch were collected. For 41 batches (3603 pigs), information about carcass quality were also collected. Pneumonia lesions were found in 59.6% of the lungs (range 3-91%), and the average batch score was 2.11 (range 0.03-7.15). We identified as farm risk factors those related to an increase in the severity of the lung lesions, the presence of breeders within the herd, the starting of a growing cycle during the winter season and the lack of vaccination programmes to Mycoplasma hyopneumoniae. Moreover, we also found a statistically significant association between the increase in the mean lung score of the batch and the decrease of the carcass quality.     

Factors affecting productivity of Rambouillet ewes mated to ram lambs

Objectives of this study were to estimate the magnitude of the effects of various factors associated with ewes and their ram lamb mates on fertility, prolificacy, lamb survival, lamb weaning weight and ewe productivity and to estimate the heritability and repeatability of each trait. Records from 731 ewe-years, 75 ram lamb sires and 616 lambs born from the University of Illinois Rambouillet flock were used. Ewes mated to single-born ram lambs had higher fertility rates (P less than .01), gave birth to lambs with higher survival rates (P less than .01), weaned lighter (P less than .05) individual lambs but weaned more weight of lamb per ewe exposed (P less than .01) than ewes mated to multiple-born ram lambs. Ram lamb breeding weight, ram lamb scrotal circumference, ewe breeding weight and ewe age had relatively large and positive effects on the composite trait of weight of lamb weaned per ewe exposed and significant effects on a number of the component traits. Heritability and repeatability estimates were, respectively, as follows: fertility, 3%, 3%; prolificacy, 34%, 19%; lamb survival, 15%, 8%; lamb weaning weight, 7%, 36%; and ewe productivity, 27%, 10%.     

Use of a Giemsa stain to detect changes in acrosomes of frozen ram spermatozoa.

Acrosomal structures of ram spermatozoa were prominently stained when air dried smears of diluted semen were fixed for 15 minutes in buffered formal saline and stained for 90 minutes in a 6 per cent (v/v) buffered solution of Giemsa stain. Progressive disruption of the acrosomes was demonstrated during chilling and deep-freezing of the spermatozoa, and the degree of damage was systematically scored. A rapid and repeatable estimate of the state of the acrosomes in a sample could be made from the mean score of 20 spermatozoa examined per slide.     

Pregnancy diagnosis and assessment of fetal viability in the dog: A review

Abdominal palpation and radiography are the techniques generally used by the veterinary surgeon for pregnancy diagnosis in the dog. Diagnostic ultrasound is an imaging modality which has been widely used in human obstetrics for many years. It is now clear that ultrasound can provide useful information about the canine pregnancy, particularly with respect to fetal viability. The advantages and limitations of abdominal palpation, radiography and ultrasound for pregnancy diagnosis and assessment of fetal viability in the dog are discussed.     

农村规模猪场饲养管理的改善

规模养殖是传统畜牧业向现代畜牧业转变的必由之路,它可以集科学技术、现代管理、先进的生产工艺于一体,是转变畜牧业增长方式的有效途径.     

Genital infection of ram hoggets associated with a gram-negative pleomorphic organism

Abstract

Extract

An acute epididymitis affecting mainly young rams and associated with a gram-negative pleomorphic organism was first reported in New Zealand in 1955 (1) Dodd, D. C. and Hartley, W. J. 1955. A specific suppurative epididymitis of rams. N.Z. vet. J., 3: 105–110. [Taylor &; Francis Online] , [Google Scholar]. Subsequently a similar syndrome attributed to Actinobacillus seminis has been reported in Border Leicester and other rams in Australia (2) Baynes, I. D. and Simmons, G. C. 1960. Ovine epididymitis caused by Actinobacillus seminis. N.Sp. Aust. vet. J., 36: 454–459.  [Google Scholar] (3) Simmons, G. C., Baynes, I. D. and Ludford, C. G. 1966. Epidemiology of Actinobacillus seminis in a flock of Border Leicester sheep. Aust. vet. J., 42: 183–187.  [Google Scholar] (4) Baynes, I. D. and Simmons, G. C. 1968. Clinical and pathological studies of Border Leicester rams naturally infected with Actinobacillus seminis. Aust. vet. J., 44: 339–343.  [Google Scholar]. A like condition also described in Australia in a single crossbred ram was causally attributed to Histophilus ovis (5) Claxton, P. D. and Everett, R. E. 1966. Recovery of an organism resembling Histophilus ovis from a ram. Aust. vet. J., 42: 457–458.  [Google Scholar]. Actinobacillus seminis was isolated from an epididymal infection in a Rambouillet ram in America (6) Livingston, C. W. and Hardy, W. T. 1964. Isolation of Actinobacillus seminis from ovine epididymitis. Am. J. vet. Res., 25: 660–663.  [Google Scholar] and from a Dorper ram in South Africa(7) Worthingron, R. W. and Bosman, P. P. 1968. Isolation of Actinobacillus seminis in South Africa. J I. S. Aft. vet. med. Ass., 39: 81–85.  [Google Scholar].