Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 4

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: glikoproteiny ciazowe

Sortuj według:

Ogranicz wyniki do:

Charakterystyka rodziny glikoprotein ciazowych PAG [Pregnancy-Associated Glycoprotein]: genow oraz produktow ich ekspresji u swini domowej [Sus scrofa]

100%

Szafranska B.

tom 55

1-96

Nowsze możliwości diagnozy ciąży u przeżuwaczy - ograniczenia, zalety, wykorzystanie

67%

Jaskowski J. M. , Herudzinska M. , Kmiecik J. , Kierbic A. , Jaskowski B. M. , Gehrke M.

nr 06

Early pregnancy diagnosis in ruminants, especially in high production herds, is one of the most important components of reproduction management. Reducing the time between insemination and the exclusion or confirmation of pregnancy is of major economic importance. That is why the traditional method of pregnancy examination by transrectal palpation is increasingly complemented by additional tests, such as ultrasonography. An alternative to these methods of pregnancy diagnosis are also simple field tests. The best known are tests for progesterone and estrone sulphate concentrations. Over the last few years, the measuring of pregnancyassociated glycoproteins (PAGs) has also been gaining popularity. In cattle, this method can be used as early as the 28th day of pregnancy, when the plasma concentration of PAGs exceeds 1ng/ml. Maximum values of pregnancy-associated glycoproteins are observed about day 240 after fertilization. After calving, their level quickly decreases. In sheep, the concentration of PAGs increases significantly in the 3rd and 4th weeks of gestation and reaches its maximum level around the 9th week. In goats, the concentration of PAGs differs between races, but its measurement can be quite a reliable indirect method of pregnancy diagnosis. The PAGs value in this species grows until about the 8th week after insemination and, depending on the breed, reaches a maximum value of 50 to 69 ng/ml. One limitation for the use of PAGs field tests may be false positives which occur after the death of the embryo. Similarly, an increased PAGs concentration can persists for up to about 70 days after calving. Moreover, the PAGs concentration is also affected by the health, age and milk production of the female. The advantages of field tests are the simplicity of performance, the ease of reading and interpreting the results and the short time needed to complete the entire procedure. Field tests based on the commonly used ELISA method are characterized by low invasiveness (blood, milk), combined with high sensitivity and specificity. Their rapid application under field conditions makes them an excellent extension of diagnostic capabilities, especially in large herds of cows.

Wczesna diagnostyka ciazy u krow oparta o wspolczesne metody

59%

Ptaszynska M.

Magazyn Weterynaryjny

2009

tom 18

nr 10

1100

Współczesne metody wczesnej diagnozy ciąży u krów

59%

Racewicz P. , Jaskowski J. M.

Medycyna Weterynaryjna

2013

tom 69

nr 11

Contemporary methods used in early pregnancy diagnosis (ePD) in cows have been presented. Despite many new diagnostic tests, the choice methods still remain per rectum palpation and ultrasound examinations (US). The clinical examination is performed about 35 days post insemination, US at about 28 days. When compared to per rectum examination, early ultrasound pregnancy diagnosis (eUSPD) in cows enables an earlier diagnosis or exclusion of pregnancy, confirming of viability and/or evaluation of fetus growth. Ultrasound imaging is a relatively simple and safe noninvasive technique. Accuracy (ACC), sensitivity and negative predictive value for pregnancy diagnosis using miniature, portable ultrasounds equipped with sector or linear probes assessed in 30th day after insemination is 83, 83.2 and 79.6% or 89.4, 95.2 and 91.9% respectively. Relatively low accuracy of ultrasound examination depends of both false negative and positive results. Accuracy is also influenced by such factors as: operator’s experience, technical parameters of the apparatus, individual traits of animals, and environmental conditions. Accuracy of eUSPD could be lowered in the case of pregnancy loss. Included in indirect methods of pregnancy diagnosis is examination consisting in qualitative and quantitative detection of specific substances in systemic fluids (blood, plasma and cot) produced during pregnancy. These are: early pregnancy factor ECF detection, progesterone concentration, PAG, IGF-1 and estrogen, test of specific protein B (PBSP) in blood plasma concentration. On the other hand, highly useful in the evaluation of embryo mortality in early pregnancy is the estimation of pregnancy protein DG29. However, due to their low efficiency (time consuming and low accuracy) these tests are not widely applied in practice. All methods of pregnancy diagnosis in cows should be characterized by high accuracy. Most of them have those features, but none of them combine all of them. It would seem that in the future early pregnancy diagnosis should be directed toward diagnosing based on quick, sensitive and inexpensive qualitative tests as well as completing ultrasound examinations.