THE INFLUENCE OF BOAR AGE ON EJACULATE QUALITY

. Semen was harvested in two stages from boars aged 3, 4 and 7 years. In the first stage semen was collected at 2 and 3 day intervals and in the second stage after 7 days. The quality of ejaculates collected twice a week increases with boar age from 3 to 4 years. After 4 years ejaculate quality is reduced. Semen collected once a week has a higher concentration and the spermatozoa an increased motility. Sperm motility is remarkable especially in boars aged 5 and 7 years. A decrease in collection frequency does not alter the dynamic of ejaculate volume and the 4 years old boars are still the most valuable, independent of frequency. The boars’ usage for semen collection can be prolonged if the animals maintain their reproductive ability

INFLUENCE OF HARVEST FREQUENCY ON THE QUALITY OF BOAR SEMEN

Semen was harvested from 4 boars at intervals of 3, 4, 5 and 7 days. The following parameters were assessed: volume, concentration, motility, the number of doses per ejaculate and the sexual behaviour of the animals. Results indicate that reducing the interval between successive harvests induces a decrease in volume, concentration and number of doses per ejaculate. Motility and sexual behaviour of males were not significantly changed. If semen is harvested daily the volume and concentration decrease further and from the third or fourth day onward boars refuse to jump on the dummy

THE ENERGY SUBSTRATE REQUIREMENTS CONCERNING IN VITRO DEVELOPMENT OF EARLY CLEAVAGE-STAGE SWINE EMBRYOS

Differences between the results of in vitro swine embryo development are due to little knowledge of the culture influence factors like provenience of biologic material. culture system involved or the composition of media that differ from one study to another. Considering this. there is a need for more studies in order to optimize culture conditions as well as for elucidating the specific of preimplantation embryo`s metabolism. This is the main goal of this study. where after in vitro production of swine embryos. these were cultured in glucose. lactate and pyruvate supplemented media under different combinations. The results allowed us to elucidate at least the early preimplantation embryo`s preferences for energetic substrate

THE EFFECT OF SEVERAL α-TOCOPHEROL CONCENTRATIONS ON SWINE OOCYTE MATURATION

Free radicals play significant roles in the physiological processes happening in the ovary such as steroidogenesis, folliculogenesis, corpus luteum progesterone release and degeneration, and follicle rupture during ovulation. As defence, living systems employ antioxidants that they either produce or take up from the environment. Among these are ascorbic acid and α-topherol that have been shown to improve swine oocyte maturation and the development of bovine and swine embryos. The goal of this study was to establish the influence of several ascorbic acid and α-tocopherol concentrations on swine oocyte maturation in order to improve oocyte maturation media. Pig oocytes were cultured for 48 hours at 37°C in 5% CO2 atmosphere, in M199 containing several α-tocopherol (5, 10, 20, 40 and 80 mM) concentrations. 48 hours after incubation cumulus expansion was assessed. The addition of 20 mM α-tocopherol to the maturation medium lead to a significant (

EGGS WEIGHT INFLUENCE ON THE INCUBATION OF LIGHT HEN BREEDS EGGS

The experiment amterial was represented by a lot of reproduction hens, Rosso SL 2000 parents for egg consumption. During the period of the flat level of egg laying curbe (35 – 49 weeks) from these hens weekly were harvested eggs which were after that grouped related to their weight in the small (50 – 57 g), medium (58 – 62 g) and big (63 – 68 g) eggs categories and then were incubated. Incubation indexes followed were the fecundity, dead embrios and hatching percent. The highest level of fecundity was realised earlier in the big eggs category and then decrease gradual. Dead embryos percent has higher values during the first week of incubation. In the next two weeks decreases, but as a fact of a bad incubation regime. For the big and small eggs the dead embryos percent is highe

RESEARCH CONCERNING REFRIGERATION OF RAM SEMEN IN EXTRA SEASON OF REPRODUCTION

The research was made at SCDP Jucu, between 17 of April and 23 of June 2006, as regarding the study of the ram semen quality, obtained in extra season and processing by refrigeration. For the refrigeration, there were processed ten semen samples obtained from two Laitiere Belge rams and one Suffolk ram, for refrigeration there were used three types of protocols, being distinct depending on the initial temperature and the rhythm in which the latter was lowered to the preservation value. The quality parameters of the raw ram semen (mobility, concentration and sperm abnormalities) were included in normal limits, essential differences didn’t exist in comparison with those obtained in the reproduction season. The interval of keeping the sperm mobility in the period of storage at 4ºC is major influenced by the dilution degree and by the ram(individual)