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The investigation was carried out on 6627 boars ejaculates collected from the following breeds: Polish Large White, Polish Landrace, Pietrain, Duroc × Pietrain. Ejaculates were obtained in 2003–2008 in Breeding Centre for Animal Reproduction in Łowicz. The aim of this study was to assess the impact of boars breed and season on some characteristics of ejaculates: volume, sperm concentration, % of live sperm in the ejaculate. Among the four studied breeds, the largest volume of ejaculate was found in Pietrain, when the smallest one in Duroc × Pietrain. The concentration of spermatozoa in ejaculates was the highest in Durock × Pietrain and the lowest in Pietrain breed. The lowest % of live spermatozoa in the ejaculate was observed for PL. The parameters of ejaculates was also infl uenced by the month of collection. The largest volume of ejaculate was found at autumn-winter season. In these months the concentration of spermatozoa was the lowest. The highest concentration of sperm and a high % of live spermatozoa were noticed in ejaculates collected during the late winter and spring time. It was prooved that the season and breed has an effect on the volume, sperm concentration and the ratio of live sperm in ejaculates obtained from AI boars.
The influence of farmers creating an environment for domestic animals and its impact on their behaviour and welfare are recently a major area of research. The animal reaction to human presence depends on the previous experience and their genetic characteristics. Easily handled animals are much more desirable than nervous ones. Temperament is one of the natural traits of an animal influencing, among others, daily body weight gains up to weaning, as well as meat quality when slaughtered. Some of the results based on temperament tests are summarized in the presented paper.
Calving course of 100 cows of Limousine breed covered by bulls of the same breed as well as 100 cows of Polish Holstein-Friesian breed inseminated with Limousine bull's semen was investigated. In purebred population the material was taken from the beef cattle recording scheme provided by the Polish Association of Beef Cattle Breeders and Producers. In case of commercial crossing the material was taken from the questionnaires collected by the technicians representing Mazovian Centre of Animal Breeding and Reproduction in Łowicz. The data base covered calving course degree and calf body weight at birth degree. It was proved, that the significantly higher ratio of deliveries when human help was needed was stated in the purebred Limousine population (14%), in comparison to crossbreeding where the above mentioned ratio was only 7%. The most difficult calvings were observed for the calves of the highest birth weight. The high ratio of assisted calvings in commercial crossing as well as in purebred population of Limousines suggest that all of the deliveries should be monitored by the breeders. It should be also stated that the ratio of difficult calvings in the commercial crossing is significantly lower than that observed in purebred PHF population. Because of so low ratio of assisted calvings in commercial crossing with Limousine bulls it should be recommended to use the semen of bulls which pedigree show high body weight at birth and muscularity.
As a consequence of the untypical characteristics associated with the reproductive physiology of dogs the research on the IVP in this species has not been effective. The whole IVP procedure is preceded by a stage of oocytes collection, the quantity and quality of which may in the future affect the number and ability of the development of embryos. In the presented paper methodologies used in the collection, evaluation and selection of oocytes in dogs are summarised.
Out of numerous reproductive biotechniques applied in domestic animals, as far as dogs are concerned, it was only possible to obtain in vitro embryos, and to clone a dog, though the results are still unsatisfactory. Until now, transferring in vitro embryos to bitches has produced no offspring. Paradoxically, it has been possible to obtain puppies by cloning. In contrast to farm animals and primates, the problem with obtaining in vitro dog embryos results from the enormous role of the bitch’s oviduct especially during oocyte maturation as well as fertilisation and early embryo development. For this reason, it is very difficult to optimise in vitro conditions, and the adoption of in vitro procedures used in others species is ineffective. Therefore, it is necessary to undertake detailed studies of the dog’s procreation physiology and the functions of different elements of the environment of maturing oocytes, and developing embryos, as well as the factors affecting these processes.
The efficiency of the in vitro maturation of canine oocytes is still relatively small. The periovulation period in dogs is different from that in other animal species. This study presents the results of research on the use of various media and substances, such as serum and serum albumin, hormones, energy substrates, antioxidants, antibiotics, antimycotics, and other compounds supporting the maturation of oocytes in vitro. It also describes the methods of culturing oocytes (incubation in a drop, incubation with somatic cells, incubation in the isolated oviduct and in isolated follicles). If the research on conditions simulating the oviduct environment is continued, it may become possible to obtain a higher number of oocytes capable of fertilization than at the present time.
Celem badań było określenie wpływu poziomu żywienia loch w ciąży niskiej (41.-70. dzień) na ich kondycję i wskaźniki biochemiczne oraz hormonalne krwi w okresie ciąży i przy odsadzeniu prosiąt. Obserwacjami objęto 16 loch F1 (pbz x wbp), przydzielonych losowo do grupy kontrolnej (K) lub doświadczalnej (D), żywionych indywidualnie mieszankami pełnoporcjowymi o zalecanej wartości pokarmowej dla loch prośnych i karmiących. Lochy z grupy D od 41. do 70. dnia ciąży otrzymywały o 30% większą dawkę paszy (0,7 kg/szt./dzień) niż lochy z grupy K żywione standardowo. Od wszystkich loch pobrano trzykrotnie krew (v. cava cranialis): przy kryciu, w 70. dniu ciąży i przy odsadzeniu prosiąt (35. dzień), i oznaczono wskaźniki biochemiczne: ALB, TP, ALP, GLU, CHOL, TG, CREA, UREA, hormony – GH i INS oraz Fe. Okresowe, trwające 30 dni żywienie loch prośnych podwyższoną o 30% dawką paszy miało pozytywny wpływ na przyrost masy ciała i zasoby tłuszczu oraz białka w organizmie loch. Samice żywione obficiej w okresie ciąży były w lepszej kondycji hodowlanej po odchowaniu potomstwa niż lochy żywione umiarkowanie. Podwyższona dawka paszy spowodowała wystąpienie wzrostu kompensacyjnego, co świadczy o zasadności stosowania obfitszego żywienia samic w tym okresie fizjologicznym. Zastosowany czynnik badawczy wpłynął na zmiany poziomu hormonu wzrostu i fosfatazy alkalicznej w 70. dniu ciąży, w porównaniu z okresem krycia. Stwierdzono obniżenie stężenia GH (o 20%) oraz ALP u loch z grupy D, w porównaniu do K, przy zachowaniu stabilności różnic między grupami dla pozostałych badanych wskaźników biochemicznych i insuliny. Między grupami nie stwierdzono różnic potwierdzonych statystycznie dla badanych wskaźników biochemicznych, hormonów i Fe, co wskazuje, że zastosowana zmiana poziomu żywienia umożliwiała zachowanie homeostazy organizmu.
A 3-year study was conducted under the programme ‘Healthy Cow’, initiated by the SPOMLEK Dairy Cooperative, focusing on milk production and economics. Despite diverse and not always favourable cyclical conditions, the economic efficiency of the farms analysed has improved, as relative profitability increased from 107% to 116% over the last 3 years. The improved economic efficiency of the farms is linked to progressive trends in the cows’ milk yield and in the price of milk. Milk prices at these farms were significantly higher than the national averages. The average price of milk during the period analysed ranged from 1.22 to 1.42 PLN per L, while unit costs ranged from 1.18 to 1.27 PLN per L of milk. The results indicate improved use of farm assets. In 2012 income fully covered total costs.
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