[Effect of the type of restraint of sheep during artificial insemination on their fertility]. / Vliianie na vida na fiksirane na ovtsete pri izkustveno osemeniavane vurkhu tiakhnata zaplodiaemost.

Studies were carried out to establish the effect of the various methods of restraining the sheep at their artificial insemination on the rate of conception. It was found that as a result of the fixing technique practiced up to then with sheep stress conditions developed that varied in number and effect, which led to a lower conception rate. The use of a new technique and technology of fixing and inseminating the sheep, with which all unfavourable stress factors were fully avoided, raised the conception rate by 7 to 14 per cent. A new equipment was used that made unnecessary the driving, seising; and lifting the animals as they themselves passed onto the platform for fixing and insemination. With the employment of the new method the enhanced vaginal contractions, which stood in the way of proper insemination, were lowered from 26 to 8.2 per cent as against the old technology. The new equipment further made it possible to shorten the time of inseminating each animal twice to three times and thus shorten the time for the semen to stay out of the animal body. This, in turn, also produced a favourable effect on the impregnation of sheep.

[Sperm foreward movement in the female genital tract of sheep]. / Izsledvane vurkhu pridvizhvaneto na spermatozoidite v zhenskiia polov aparat pri ovtse.

Investigations were carried out to establish the effect of deep freezing, extent of dilution, and site of applying the spermatozoa as well as the functional state of the female genital apparatus of sheep on the forward movement of spermatozoa. It was found that at the insemination of ewes with freshly obtained undiluted semen at the 30th min following insemination there were single live spermatozoa, in the oviducts their number gradually increased up to the fourth hour, reaching several thousand. The highly diluted semen was found to produce an unfavourable effect on the movement of spermatozoa. Following deep freezing spermatozoa manifested a sharp decrease in their movement capacity. Deep cervical application led to an increased number of spermatozoa reaching the oviducts, however, this number was essentially lower than with freshly obtained semen. The movement of spermatozoa depended also on the functional status of the female sexual apparatus. There were considerably more spermatozoa in that of the oviducts on the side of which ovulation took place.

[Role of rams in the epizootiology of salmonellal abortion in sheep]. / Roliata na kochovete v epizootologiiata na salmonelozniia abort po ovtsete.

Studied was the susceptibility of rams to a Salmonella abortus ovis infection. It was found that the animals could resist the oral experimental infection when the causative agent was introduced in the form of 20 ml broth culture or when the environment was contaminated with it. The Salmonella abortus ovis infection was found to be transmitted from infected rams to normal ewes and vice versa, chiefly through sexual route.

[Penetrating capacity of bull spermatozoa in vitro]. / Prouchvaniia vurkhu pronikvatelnata sposobnost na spermatozoidi ot bik in vitro.

Studies were carried out on the penetrating capacity of bull spermatozoa in an estrous secretion, a modification of Kremer's method being employed by the authors. The new method seemed to be more readily applicable in the practice. It was found that the penetrating capacity was highest following thawing of semen at 39 degrees C, the pH value of the secretion being 6.8-6.9. The adding of the cytochrome C enzyme to the spermatozoa at the rate of 1 mg/cm3 of such semen increased the penetrating capacity by 22 per cent. When the thawed semen was allowed to stay for fifteen minutes the penetrating capacity of spermatozoa in the estrous++ secretion dropped by 33 per cent.

[Salmonella abortus ovis carrier state in dogs and rats]. / Prouchvaniia vurkhu nositelstvoto na Salmonella abortus ovis pri kucheta i plukhove.

Serologic and bacteriologic investigations were carried out with 10 dogs, guarding sheep flocks with and without Salmonella abortions, and 17 grey rats. It was found that both species of animals could harbour Salmonella abortus ovis provided they swallowed infective material (aborted fetuses and fetal membranes). It was shown that although lasting but 2 to 3 months only the carrier state could play a definite part in the epizootiology of Salmonella abortions in sheep.

[Protein fractions in diluted bull seminal fluid with various biological indices after thermal treatment]. / Izsledvaniia vurkhu beltuchnite fraktsii na razredena semenna technost ot bik s razlichni biologichni pokazateli sled termichna obrabotka.

Studied were electrophoretically the protein fractions of bull semen after heat treatment of the GH22L extender. Studied were also the changes in the protein fractions of diluted semen of various biologic indices. It was found that after heat treatment of the extender at 70 degrees C for 60 min. most stable proved the fractions that were at the front and the start. Negligible changes underwent the proteins of the 3rd and 4th fraction. The changes in the percent distribution of the protein fractions of diluted qualitative and unqualitative bull semen at 1+2 degree with thermically untreated GH22L extender were best manifested with the semen of lower quality. Weaker were the changes taking place with dilution of qualitative and unqualitative semen at 1+6 degree. These changes were observed also with dilution at 1+2 with thermically treated extender (70 degrees C for 60 min.). Dilution of qualitative semen with thermically treated (at 1+6) extender most strongly changed the proteins of the 1st, 2nd, and 3rd fraction. The proteins of the start showed high stability. Nonsignificant were the changes with unqualitative semen with which all fractions showed great heat stability.

[Survivability and penetration capacity of bull spermatozoa frozen by 3 technics]. / Prezhiviaemost i penetratsionna sposobnost na spermatozoidite ot bik, zamrazeni po tri razlichni tekhnologii.

Studied was the survival and penetration capacity of bull spermatozoa frozen after the following technologies--pellet, straw, and minitube--and the results obtained were compared via biologic experiments. The minitube technology of freezing the semen led to higher thermal resistance of the spermatozoa as against freezing in the form of straws and pallets (363.5 +/- 8.02 min, 356.25 +/- 7.79 min, and 339.00 +/- 8.44 min, respectively). The differences established were statistically highly significant (P less than 0.001). The penetration capacity of spermatozoa in an estral secretion of cows was highest at freezing in the form of minitubes (1.70 +/- 0.54 mm/min). The same was lower with straws (1.53 +/- 0.02 mm/min), and lowest--with pellets (1.52 +/- 0.04 mm/min). The differences were statistically significant (P less than 0.01). The fertilization capacity of spermatozoa frozen with the employment of the three technologies was best with the use of minitubes and straws--50.20, resp., 49.67 per cent, and lowest with the use of pellets--45.22 per cent.

[Zinc and manganese transport in ram sex cells]. / Vurkhu tsinkoviia i manganoviia transport pri polovi kletki ot koch.

The atomic absorption spectrophotometer AAS1 was used to determine the concentration of Zn and Mn in the spermatozoa and ejaculate plasma of rams, having different percent of motile spermatozoa. A reverse correlation was found between the Zn and Mn content of spermatozoa and the percent of their motility. Seminal fluid with a higher percent of motile cells had plasma with a higher Zn and Mn content as compared with ejaculates having plasma with a lower percent of motile spermatozoa.

[Cryobiological characteristics of bull sperm]. / Niakoi kriobiologichni osobenosti na sperma ot bik.

Investigations were carried out on the concentration of live spermatozoa and their viability in various layers of the pellets of frozen bull semen. Studied were also the 'nests' of dry snow for the presence of organisms and spermatozoa and the likeliness of their transmitting into the pellets of frozen semen. It was found that the concentration of live spermatozoa and their viability were highest in the central part (core) of the pellets, and lowest--in the peripheral layers. At freezing the semen following the pellet technology of Nagaze Niva there was the hazard of contaminating the pellets with organisms that remained from the preceding frozen ejaculates in the nests of dry snow. During the process of pelleting the semen the nests might enable the transference and mixing of spermatozoa of various breeds of animals, as live spermatozoa were found on their walls.

[Case of a leiomyoma in the uterus and cervix of a sheep]. / Sluchai na leiomiom v matkata i tserviksa na ovtsa.

Morphologic studies were carried out on the genital organs (uterus, cervix, oviducts, and ovaries) of a 3-year-old sterile sheep. A gross lesion was found in the region of the uterine bifurcation, consisting of a tumor-like formation of a 3 cm dia, pale gray cross-section surface, and elastic to hard consistence. Histologically, proliferation was seen of the smooth-muscle cells in various directions within the uterus and cervix. It was demonstrated to be a primary leiomyoma, originating from the myometrium. Its gross and microscopic appearance resembled the leiomyomas found in the remaining parts of the body of other mammals and man. The endometrium presented desquamation of the protective epithelium, necrobiosis of the uterine glands, activation of the local cell elements, and oedema of the stroma. There were persisting corpora lutea, atretic follicles, and sclerotic changes in the ovaries. No changes were found in the oviducts.

[Effect of biologically active substances on the alkaline phosphatase activity, viability and fertility of bull spermatozoa]. / Vliianie na niakoi biologichno aktivni veshtestva vurkhu aktivnostta na alkalnata fosfataza, zhiznesposobnostta i oploditelnata sposobnost na spermatozoidi ot bik.

Studied was the effect of beta-glucuronidase, hydrocortisone, and mercaptoethanol in bull semen on the activity of the alkaline phosphatase and the viability and fertilizing capacity of spermatozoa. It was found that the beta-glucuronidase enzyme in conc. of 270 UI per cu. cm of semen enhanced the activity of one of the forms of AP in agar electrophoresis (AP-1) with the simultaneous enhancement of the thermal resistance of spermatozoa at 46 degrees C and their fertilizing capacity by 9.6 per cent at first insemination. At minimum concentration hydrocortisone (1 X 10(-6) M) lowered the heat resistance of spermatozoa at 39 degrees C. Mercaptoethanol was found to lower by 3 per cent the activity of semen alkaline phosphatase. It is suggested to use the beta-glucuronidase enzyme in the practice of artificial insemination out of all other biologically active agents studied.