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Interaction of bovine chorioallantoic membrane explants with three strains of Brucella abortus
1992
Samartino, L.E. | Enright, F.M.
Chorioallantoic membranae (CAM) explants were used to determine the in vitro growth and cytotoxic potential of 3 strains of Brucella abortus. Bovine CAM explants were inoculated with 2 X 10(7) colony-forming units of the pathonic strain 2308, attenuated strain 19, or the rough strain RB51 of B abortus. After inoculation, the explants were harvested and examined at 2 or 4 hours, 12 or 14 hours, and 24 or 26 hours of incubation. Bacterial growth associated with each explant was determined by counting colony-forming units. The degree of cellular damage in each explant associated with bacterial growth or bacterial toxins were evaluated by morphometric analysis after trypan blue staining. Significant differences were not detected in the numbers of bacteria of any strain of B abortus in the CAM explants at comparable time intervals. The rate of growth of the bacteria in CAM explants was higher between 2 and 12 hours after inoculation than between 12 and 24 hours after inoculation. Cytotoxic effects associated with strain 2308 were significantly (P < 0.05) greater than that caused by other strains. Cytotoxic effects associated with strain 19 and rough strain RB51 were similar, and both were significantly (P < 0.05) greater than the phosphate buffer solution control. Chorioallantoic membrane explants inoculated with a filtrate of heat-killed strain 2308 induced minimal cellular damage, compared with that caused by the viable bacteria. These results indicated that the number of B abortus in trophoblasts was independent of the degree of cellular damage.
Показать больше [+] Меньше [-]Growth hormone concentrations in plasma of healthy pigs and pigs with atrophic rhinitis
1991
Ghoshal, N.G. | Niyo, Y. | Trenkle, A.H.
Plasma concentrations of porcine growth hormone (PGH) were similar in healthy pigs and those with atrophic rhinitis (AR), therefore, observed reduced growth rates and feed efficiency in naturally infected pigs with AR were not attributed to low concentrations of plasma PGH. Also, pituitary glands in both groups of pigs were responsive to growth hormone-releasing hormone (GHRH) challenge by increasing PGH secretion. Administration of clonidine hydrochloride to pigs naturally infected with AR failed to elicit any significant change (5.3 +/- 1.4 ng/ml) in the plasma concentration of PGH within a 45-minute bleeding interval. The pretreatment concentrations of PGH were similar in specific-pathogen-free toxin-treated and specific-pathogen-free control groups, but they increased significantly in toxin-treated pigs (20.7 +/- 8.2 ng/ml) within 15 minutes after GHRH injection. Porcine growth hormone release in toxin-treated pigs was variable; however, all pigs did not respond to GHRH administration: 3 responded with an increase in PGH release (35.6 +/- 10.6 ng/ml), 2 did not respond (6.7 +/- 0.5 ng/ml), and 1 had a decrease in PGH release (3.9 ng/ml). Therefore, the observed reduced growth rates reported in the literature may be attributed to factors at the target level of PGH action, such as insufficient or down-regulation of PGH receptors, changes or impaired ability in the PGH receptor-binding characteristics, and inability of PGH receptor complex to transduce signal. Toxins are known to modulate signal transduction pathways. It has been speculated that serotype-D Pasteurella multocida toxin may influence growth by its effect on signal transduction from PGH receptor complex on the cell membrane to the interior of the cell. This would account for the presence of high concentrations of PGH in the plasma and a functionally competent hypophysis cerebri, which responded to GHRH injection that have retarded growth in pigs affected with AR.
Показать больше [+] Меньше [-]SPATIO-TEMPORAL ANALYSIS OF BUFFALO POPULATION AND MILK PRODUCTION IN TAMIL NADU
2023
S. Vignesh | P. Devendran | T. Sivakumar | G. Senthilkumar
Growth dynamics of buffalo population and milk production and productivity in Tamil Nadu was analysed. Point to point annual compound growth rate (ACGR) was calculated to assess the trend in buffalo population and continuous annual compound growth rate (ACGR) for milk production and productivity. The share of Tamil Nadu to National buffalo population decreased from 5.29 to 0.72 % (1951 to 2012) and the buffalo milk production reduced from 4.01 to 0.46% (2001-02 to 2015-16). The ACGR of buffalo population in Tamil Nadu was -17.23% during the last inter-census period (2007-12). North Eastern and Cauvery Delta agro-climatic zones of Tamil Nadu registered high negative growth. The annual compound growth rate of buffalo milk production during 2011-12 to 2015-16 in Southern zone was -27.37% and it was - 21.72% in North Eastern and -20.93 % in Cauvery Delta zone with overall ACGR of -16.85%. The ACGR of buffalo milk productivity was 0.61% (2001-02 to 2015-16) in Tamil Nadu, while the rate was 1.58% in India. Hence, rigorous implementation of buffalo development programmes is a prime requisite and need of the hour for improving buffalo population and milk production in Tamil Nadu.
Показать больше [+] Меньше [-]Use of primary quail embryo fibroblast cells for propagation and assay of avian viruses
2015
Hasoon, Mayada F. | Mohammed, Majed H. | Jubrael, Jaladet M. S.
A primary fibroblast cells from embryos of brown quail Coturnixypsilophora has been established and partially characterized. The cells were maintained in Modified Eagle’s medium (MEM) supplemented with 10% fetal bovine serum. The cells were able to grow at temperatures between 35°C and 38°C with optimum temperature of 37°C. The growth rate of primary quail fibroblast cells increased as the FBS proportion increased from 5% to 20% at 37°C with optimum growth at the concentrations of 10% or 15% FBS. The cells showed no microbial contamination throughout the period of experiment and the total chromosome number of a diploid cell was 78, according to karyotyping and chromosome analysis. The susceptibility of quail primary cells for avian viruses was investigated in this study after inoculation with ND and IB viruses. Both viruses showed a satisfactory CPE development and the infectivity were assayed by virus titration (TCID50). This suggests that the quail primary cells can be used for isolation of various avian viruses with further steps of infectivity confirmation in the future.
Показать больше [+] Меньше [-]A genetic improvement program for Kedah-Kelantan cattle
2012
Raymond A. K. | Abu-Hassan M. A.
Kedah-Kelantan cattle (KK) being an indigenous breed are highly adapted to the hot-humid Malaysian climate and can survive in harsh, marginal environments. This makes the KK a valuable genetic resource, given the challenges of climate change and the changing demands of the livestock sector. Hitherto there is no comprehensive programme to genetically improve the purebred KK. Genetic improvement of the KK would be to fulfill the breeding objectives of increasing lean meat growth rate, enhancing meat quality, raising feed efficiency, improving fertility and maintaining adaptability. The breeding structure proposed is a 2-tier breeding structure, with a nucleus tier followed by a commercial tier below it. The nucleus tier would comprise of a number of pedigree farms run as a community
breeding project. A sire reference scheme is proposed, where progeny of reference sires are used as genetic links between pedigree herds and between years. Some guidelines are offered on the establishment
and implementation of the scheme. Modern breeding technology such as BLUP using an Animal Model, artificial insemination, embryo transfer, tissue scanning, MAS and MAI could be used as tools to support the KK genetic improvement programme. To address the problem of genetic erosion, emphasis should be given to the conservation and sustainable utilization of the KK. The programme is expected to have a high impact on the livestock sector. Substantial investments are needed to develop infrastructure and human capital associated with the KK breeding programme. The establishment of a KK breed society will improve awareness concerning the KK and protect the interests
of the KK breeding community.
Показать больше [+] Меньше [-]Continuous disinfection as a means to control infectious diseases in poultry. Evaluation of a continuous disinfection programme for broilers
2003
Bragg, R.R. (Free State Univ., Bloemfontein (South Africa). Microbial, Biochemical and Food Biotechnology Dept.) | Plumstead, P.
Влияние сроков передачи ремонтных свинок из племпродуктора в товарную часть комплекса на их продуктивные качества
2008
Perashvili, I.I., National Academy of Sciences. Scientific and Practical Center of Animal Breeding (Belarus)
The growth and development of replacement gilts of different precocity and age depending on the terms of transition from herd-producer to the market area of a complex was studied in the conditions of the Republic of Belarus. Animal transfer into new housing conditions affected the early maturing and super early maturing breed pigs of experimental groups. It was determined that moving of replacement pigs into the market area of the complex at the age of 115 days made it possible to obtain higher indices of swine productivity. Fertilization rate of sows of the first experimental group after the first insemination made up 77,6%, that was higher on 6,2% and 9,5% in comparison with the control and the second experimental groups, respectively. The advantage of the first and second experimental groups over the control one was stated in a higher multiple fetation on 0,4 heads and heightened heavy litter indices on 0,1 kg; the quantity of weanling was higher on 0,6 and 0,5 heads, on litter weight at weaning was higher on 7,1 and 3,8 kg, respectively
Показать больше [+] Меньше [-]Влияние улучшенного качества воды на организм поросят в условиях промышленного комплекса
2010
Medvedskij, V.A. | Karas, A.V. | Apenkina, L.V. | Gasanov, F.A., Vitebsk State Academy of Veterinary Medicine (Belarus)
In the conditions of the Republic of Belarus there was realized an ecological monitoring of sources of water supply in the conditions of a swine breeding complex and adjoining settlements. There was studied the influence of a large swine breeding complex on water quality of closed type water sources. There was marked a microbial contamination of water depending on remoteness of animal breeding object and season of a year. There were determined the seasonal changes of physical properties, chemical and bacteriological composition of water used for swine breeding. There were noted changes in water quality in the process of its flow from the point of water inlet up to the place of its consumption. Results of influence of improved water on piglets were presented. There was studied the possibility of improvement of water quality by means of its treatment with solution of potassium hypermanganate (0,01%) which made it possible to increase average daily live weight gain of piglets. In course of the study there was realized the analysis of protein spectrum of blood serum of piglets; dynamics of body weight and average daily weight gain of experimental piglets.
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