The development and integrity of equine pre‐antral follicles cultured in vitro with follicle‐stimulating hormone (FSH) supplementation

This study investigated the effects of different concentrations of FSH (10, 50, 100 and 200 ng/ml) in supplemented MEM+ on the development of equine pre‐antral follicles that were cultured in vitro for 2 or 6 days. The ovaries (n = 5) from mares in seasonal anoestrus were collected from a local abattoir. Ten ovarian tissue fragments of approximately 3 × 3 × 1 mm were obtained from each animal. The fragments were cultured in situ for 2 days (D2) or 6 days (D6) in MEM+ or MEM+ supplemented with FSH at four different concentrations, establishing the following 11 groups: control (D0); MEM + (D2); MEM + (D6); MEM + 10 ng/ml of FSH (D2); MEM + 10 ng/ml of FSH (D6); MEM + 50 ng/ml of FSH (D2); MEM + 50 ng/ml of FSH (D6); MEM + 100 ng/ml of FSH (D2); MEM + 100 ng/ml of FSH (D6); MEM + 200 ng/ml of FSH (D2); and MEM + 200 ng/ml of FSH (D6). Follicles were observed in only 9.65% (388 of 4,018) of the histological sections. Of the 861 follicles evaluated, 488 were in the primordial stage, and 373 were in various developmental stages; 59.7% were morphologically normal. Regarding the integrity of the pre‐antral follicles, the groups with 100 ng/ml FSH of 2‐days culture as well as 50, 100 and 200 ng/ml FSH of 6‐days culture provided the best results. In conclusion, the in vitro culture of abattoir‐derived equine ovarian fragments presented better morphological integrity when supplemented with FSH for 6 days, in comparison with the MEM culture group. However, no clear effects were observed with FSH regarding the promotion of activation from a primordial to a developing follicle.     

A phenomenological model of dry matter partitioning among plant organs for simulation of potato growth

A mathematical model of the process of dry matter partitioning among plant organs during the autotrophic period of potato development is presented. The model consists of a system of differential equations based on the concept of a sink. The sink strength is proportional to the dry matter (DM) biomass, subject to total photosynthesis production. The ageing process is taken into account. The equations contain a set of parameters which are estimated by fitting the numerical solution to the empirical data recorded from growth analysis in field experiments.     

Epizootiological investigation if strangles in the equine stables in tehran

Strangles is an acute disease of horses caused by infec- tion with Streptococcus equi. It is characterized by inflamma- tion of the upper respiratory tract and abscessation in the adjacent lymph nodes. The distribution of strangles is world- wide. When an outbreak does occur in a large group of horses, it is usually restricted to the younger age groups, under adverse climatic conditions, and when shelter is inadequate. When the group is made up of predominantly young horses, up to 100% may be affected. Such a high incidence is encountered soon after large numbers of susceptible horses, which may have come from many localities, are stabled to get her. The source of infection is the nasal discharge from infected animals, which contaminates the pasture and feed and water troughs. Infection occurs by ingestion or by inhalation o f droplets. During April (1990), two cases of strangles were diag- nosed at Veterinary Faculty Teaching Hospital in Tehran. An epizootiological survey commenced immediately and showed 89-100% of horses were affected. The clinical symp- toms were severe in young horses and the mortality rate was zero. All of the infected horses responded to treatment with intramuscular injection of penicillin/streptomycin.     

A model for simulation of potato growth on the plant community level

A model for the main processes in potato growth is developed and used for the simulation of crop production under different meteorological conditions. The main control factors considered in the model are irrigation, fertilization and timing of harvest. The model is constructed on the level of the plant community. The time interval for the simulation of general dynamic processes is one day. To describe some important physiological processes during a day, the simulation is performed by subroutines with hourly time steps.     

Brain edema: induction in cortical slices by polyunsaturated fatty acids

The presence of polyunsaturated and saturated fatty acids in leukocytic membranes prompted study of their possible role in the induction of brain edema. Polyunsaturated fatty acids including sodium arachidonate, sodium linoleate, sodium linolenate, and docasahexaenoic acids induced edma in slices of rat brain cortex. This cellular edema was specific, since neither saturated fatty acids nor a fatty acid containing a single double bond had such effect.