Wyniki wyszukiwania - AGRO

1

Preliminary observations on milk yield of improved white goats from the Podlasie Region

100%

Pieniak-Lendzion K., Szeliga W., Nowogrodzka T.

Natural Sciences

|

1999

|

tom 02

2

Development of the mammary glands in female mink from weaning through first lactation

100%

Moller S. H.

Zeszyty Naukowe. Przegląd Hodowlany

|

1996

|

tom 27

3

Development of the mammary glands during gestation and lactation in mink in relation to feeding intensity

100%

Brzozowski M., Moller S. H.

Zeszyty Naukowe. Przegląd Hodowlany

|

1996

|

tom 27

4

Effect of automatic and conventional milking on somatic cell count and lactation traits in primiparous cows

86%

Nogalski Z., Czerpak K., Pogorzelska P.

Annals of Animal Science

|

2011

|

tom 11

|

nr 3

5

A comparison of adrenal gland function in lactating dairy cows with or without ovarian follicular cysts

86%

Silvia W. J., McGinnis A. S., Hatler T. B.

Reproductive Biology

|

2005

|

tom 05

|

nr 1

6

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

The effect of age and heat term and duration on magnesium content in mares' milk

86%

Pieszka M., Kulisa M.

Journal of Elementology

|

2006

|

tom 11

|

nr 1

Skład mleka klaczy zmienia się podczas laktacji. Od tych zmian zależą tempo wzrostu i rozwoju źrebiąt, natomiast na zmiany te wpływa wiele czynników, m.in. stan fizjologiczny klaczy. Celem pracy było zbadanie wpływu wieku oraz terminu wystąpienia i długości rui na zawartość magnezu w mleku klaczy. Badania prowadzono na 30 klaczach czystej krwi arabskiej. Stwierdzono, że poziom magnezu obniżał się w ciągu 30-dniowej laktacji, szczególnie w okresie od 4. do 12. dnia po oźrebieniu. W mleku klaczy starszych była istotnie wyższa koncentracja magnezu. Także termin wystąpienia rui oddziaływał na poziom omawianego pierwiastka - klacze z rujami dawały mleko uboższe w magnez. Mleko najzasobniejsze w magnez produkowały klacze, u których ruja trwała średnio 4-7 dni.

7

Wpływ częstości doju na wydajność i skład mleka krów za pierwsze 100 dni laktacji

86%

Weglarzy K., Bereza M., Szarek J.

Prace i Materiały Zootechniczne

|

2009

|

tom 67

8

Expression of PC, PCK1, PCK2, LDHB, FBP1 and G6PC genes in the liver of cows in the transition from pregnancy to lactation

86%

Ostrowska M., Gorka P., Zelazowska B., Sloniewski K., Kowalski Z. M., Zwierzchowski L.

Animal Science Papers and Reports

|

2013

|

tom 31

|

nr 4

The effect of the transition of dairy cows from pregnancy to lactation on the expression of genes encoding enzymes involved in hepatic glucose metabolism was studied. Six Holstein-Friesian heifers were used for this study. Liver samples were collected by biopsy on day 7 before expected parturition (-7) and days 3 and 21 after parturition (+3 and +21, respectively). The mRNA levels of pyruvate carboxylase(PC),phosphoenolpyruvate carboxykinase 1 (PCK1), phosphoenolpyruvate carboxykinase 2 (PCK2), lactate dehydrogenase B (LDHB),fructose-1,6-bisphosphatase 1 (FBP1) and glucose-6-phosphatase (G6PC) were measured using quantitative real-time PCR. The expression of PC and PCK2 mRNA on day 3 of lactation was significantly higher than that on day 7 before parturition (P<0.05) and slightly higher than on day 21 postpartum. The LDHB gene showed the highest expression level on day 3 of lactation, as compared with day 7 prepartum (P<0.001) and day 21 postpartum (P<0.001). No differences were shown in PCK1, FBP1 and G6PC expression levels between pregnancy and early lactation.

9

Analysis of changes in selected hematological parameters in blood from primiparous dairy cows during last trimester of pregnancy and first two months of lactation

86%

Skrzypczak W., Kurpinska A., Baziuk M.

Acta Scientiarum Polonorum. Zootechnica

|

2022

|

tom 21

|

nr 3

10

Effect of age and heat term and length on magnesium content in mares' milk

86%

Pieszka M., Kulisa M.

Journal of Elementology

|

2005

|

tom 10

|

nr 4 Suppl.1

80

11

The influence of pregnancy and lactation on the magnesium and calcium concentration in goats' blood serum

86%

Brzezinska M., Krawczyk M.

Journal of Elementology

|

2010

|

tom 15

|

nr 1

31-37

The aim of this work was to trace differences in magnesium and calcium concentrations (both total and ionic form) between goats which were in late pregnancy and lactating goats. The study involved 30 goats. Blood samples were taken three times from each goat. Total concentrations of magnesium and calcium were determined with the colorimetric method and (A — 1.581 mmol dm-3; B — 2.052 mmol dm-3; C — 2.112 mmol dm-3). Ionic form of calcium based on using ion—selective analysis (A — 1.219 mmol dm-3; B — 1.126 mmol dm-3; C — 1.123 mmol dm-3). The study showed that mean value of both the total of calcium from each goat did not reach the reference level for this species. Ionic form of calcium was within the lever limit of the physiological norm. The content of magnesium in all the groups was within the range of reference concentrations (A — 1.051 mmol dm-3; B — 1.165 mmol dm-3; C — 1.117 mmol dm-3).

12

Relationship between milk yield of cows and their 24-hour walking activity

86%

Adamczyk K., Gil Z., Felenczak A., Skrzynski G., Zapletal P., Choroszy Z.

Animal Science Papers and Reports

|

2011

|

tom 29

|

nr 3

Despite many genetic and environmental factors, the level of physical activity may be a very good indicator of the physiological (e.g. estrus, approaching parturition) or health status of cows. The aim of this study was to analyse the 24-hour walking activity of lactating cows as related to the milk yielded in particular milkings over two stages of lactation. Used were 41 cows in early lactation (group G1) and 54 cows in late lactation undergoing a gradual decline in milk production (group G2). Activity of animals was measured with activity meters and expressed in Alpro units (AU), version 6.5 by DeLaval. The cows were kept in a loose system in one common building and milked three times a day in a milking parlour. Two hours before morning and evening milking the G2 cows occurred more active than cows G1 (43 and 45 vs. 26 and 31 AU, respectively). From morning to noon milking the G1 cows showed significantly lower activity (33 AU) than G2 cows (40 AU). The highest positive significant correlation coefficients (r) were estimated for G1 cows between milk yield at noon and mean 24-hour activity, mean activity between morning and noon milking, and mean activity associated with partial mixed rations (PMR) intake between evening milking and first (morning) PMR feeding (r = 0.47-0.48). The r coefficients between investigated indicators were generally lower in G2 than in G1 cows.

13

The record of the reproductive cycle in the incisor dentine of spotted souslik Spermophilus suslicus

86%

Trunova Y. E., Lobkov V. A., Klevezal G. A.

Acta Theriologica

|

1999

|

tom 44

|

nr 2

To examine the changes in dentine microstructure in spotted souslik Spermophilus suslicus (Giildenstaedt, 1770) during pregnancy, parturition and lactation, we investigated 39 females from the Odessa region. Thirty females were dead-trapped in March-July, 1987-1997, nine females (lactating or pregnant) were caught in April, 1996, injected with tetracycline as a time marker and kept in captivity during 14-47 days. Their litters survived from 1 to 29 days. We analyzed cross stained sections as well as cross ground sections of upper incisors. In the lactating sousliks both in nature and in captivity the daily layers formed in the course of pregnancy were followed by formation of a specific dentine pattern. The pattern consisted of alternating contrastive hypo- chromatic and hyperchromatic bands of about 30-50 n wide. The beginning of the pattern formation coincided approximately with parturition and the formation continued during lactation. Therefore, the parturition-lactation zone could be the correct name for the pattern. In captured females no correlation between the duration of the pattern formation and the lifespan of their litters was found. The pattern was absent in immature and barren females. We found no changes in the dentine formation during pregnancy.

14

Estimates of genetic parameters for protein yield of Polish Black-and-White cattle with multiple-lactation rendom regression test-day model

86%

Strabel T., Ptak E., Szyda J., Jamrozik J.

Animal Science Papers and Reports. Supplement

|

2004

|

tom 22

|

nr 2

15

Estimates of heritability for first and second lactation test-day milk production in Polish Black-and-White cattle

86%

Ptak E., Jagusiak W., Jamrozik J.

Animal Science Papers and Reports. Supplement

|

2004

|

tom 22

|

nr 2

16

Brugia malayi in Mastomys natalensis: exposure during pregnancy and lactation

86%

Tyagi K., Murthy P. K., Chatterjee R. K.

Acta Parasitologica

|

1994

|

tom 39

|

nr 3

17

The impact of rapeseed oil used in sow feeding on reproductive performance results

86%

Michalska G., Nowachowicz J., Zuraw J., Wasilewski P. D.

Annals of Animal Science. Supplement

|

2003

|

nr 1

18

Joint genetic evaluation of Nordic dairy cattle

86%

Stranden I., Lidauer M., Poso J., Mantysaari E. A.

Animal Science Papers and Reports. Supplement

|

2004

|

tom 22

|

nr 2

19

Heritabilities and genetic correlations between the dairy traits in goats estimated in first vs later lactations

86%

Bagnicka E., Distl O., Hamann H., Lukaszewicz M.

Animal Science Papers and Reports

|

2004

|

tom 22

|

nr 2

The purpose of the study was to evaluate the multiple-trait model, as opposite to repeatability model approach, at an early stage of developing the breeding value estimation system for dairy goats in Poland. Milk, fat, and protein yields and fat and protein contents in first (4,443 records) and following parities (9,115 records of 5,244 goats) were analysed as two separate traits within a trait.Variance components were estimated with REML method. Classification of dairy traits in lactation I contained random effects of animal’s additive genetic background, herd-sire interaction, and fixe effects of herd-year-season, breed, year of birth, litter size, and linear regression on days-in-milk. Traits recorded in later lactations were considered to be the same within a trait, yet of repeated measurements.Hence, statistical model additionally accounted for fixed effect of parity and random effect of permanent environment. Heritability of milk yield ranged from 0.214 to 0.247 in later lactations, and from 0.190 to 0.324 in lactation I depending on set of traits which were estimated simultaneously. For lactation I the h2 for fat yield ranged from 0.208 to 0.224 and for later lactations from 0.204 to 0.216. Heritability for protein yield ranged from 0.130 to 0.208 for lactation I, and from 0.180 to 0.201 for later lactations. Heritabilities for fat content ranged from 0.278 to 0.318 in lactation I and from 0.214 to 0.243 in later lactations. Those for protein content were between 0.397 to 0.448 and 0.276 to 0.310 for lactation I and later lactations, respectively. Repeatability coefficients for all the dairy traits In the later lactations were between 0.247 to 0.355. Phenotypic correlations between lactations for each trait exceeded 0.50 while genetic correlations ranged from 0.880 to 0.996. Correlations between yields within lactation were high and positive while those between milk yield and milk constituents contents were moderate and negative. Presented correlations follow the general pattern found In other dairy goat as well as in dairy cattle populations. It is concluded that repeatability model should better suit Polish conditions.

20

Correlations between genetic variants of milk proteins and milk yield and composition in first full lactations of Black-and-White cows

86%

Pytlewski J., Antkowiak I., Dorynek Z.

Animal Science. Scientific Papers of Agricultural University of Poznan

|

2002

|

tom 04

Ograniczanie wyników