Wyniki wyszukiwania - Biblioteka Nauki

1

Egg quality of dual-purpose hens intended for small-scale farming

100%

Dudek M. , Rabsztyn A.

Acta Scientiarum Polonorum. Zootechnica

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2011

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tom 10

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nr 1

EN

The objective of the experiment was evaluation of some physical traits of egg quality in hens originating from Polish egg-type pedigree farms and destined for small-scale farming as well as in a breed of preserved chickens. 30 eggs from each of the three genetic groups (parental P55 Barred Rock strain, VH43 parental cross of V44 Rhode Island Red and H33 Leghorn strains, and the preserved Z11 Partridge Greenleg strain) were taken to analysis. The layers were maintained in the same environmental conditions and were under the same feeding regime.Analyses of egg quality were accomplished in 26th and 50th weeks of age, with an electronic EQM device. Egg weight in VH43 cross in the beginning of laying was 61.5 g and it was significantly bigger than in P55 hens (50.2 g) and Z11 hens (42 g). No statistical differences between experimental groups were found in shell thickness, shell density. Egg shell colour in P55 hens differed significantly from that in the other groups. The highest Haugh unit score (99.9) and albumen height (9.7 mm) were noted in the eggs of P55 hens in 26th weeks of age. These parameters lowered with age in all experimental groups. The highest proportion of yolk was found in the eggs of Z11 (29.5%) in 50 weeks of age. Yolk percentage increased with age in all genetic groups. Yolk colour index (La Roche) diminished with age of layers.

PL

Celem badań była ocena wybranych cech jakości jaj pochodzących od kur z polskich ferm zarodowych przeznaczonych do chowu drobnotowarowego oraz od rasy kur objętej programem ochrony zasobów genetycznych drobiu. Materiał do badań stanowiły jaja kur Barred Plymouth Rock (P55), mieszańców VH43 oraz jaja Zielononóżki kuropatwianej (Z-11). Masa jaja kur mieszańców VH43 na początku nieśności wynosiła 61,5 g i była istotnie większa niż masa jaj kur P55 (50,2 g) i kur Z-11 (42 g). Nie stwierdzono istotnych różnic w grubości i gęstości skorupy. Zanotowano statystycznie istotną różnicę w barwie skorupy jaj między kurami P55 a dwiema pozostałymi grupami. Największą wartość jednostek Haugha (99,9) oraz wysokości białka (9,7 mm) stwierdzono w jajach kur P55 w 26. tygodniu życia. Wartości te obniżały się wraz z przebiegiem nieśności w jajach wszystkich grup genetycznych. Największy procentowy udział żółtka stwierdzono w jajach kur Z-11 (29,5). Udział żółtka wzrastał wraz z wiekiem u wszystkich badanych grup, natomiast wskaźnik barwy żółtka (La Roche) zmniejszał się.

2

Effect of diverse feeding regimes on rearing performance of Holstein-Friesian Red heifer calves

100%

Weglarzy K. , Bilik K.

Annals of Animal Science

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2008

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tom 08

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nr 2

145-154

3

ENSO affects sex ratio progeny in captive Iberian red deer despite a steady feeding regime

84%

Estevez J. A. , Landete-Castillejos T. , Garcia A. J. , Gaspar-Lopez E. , Ceacero F. , Gallego L.

Acta Theriologica

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2011

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tom 56

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nr 4

EN

Climate variability greatly affects animals through direct and indirect effects. Animals with slow reproductive adaptation to ecological changes such as large mammals are likely to have evolved mechanisms to anticipate early such impacts of climate variability on the environment. One of the adaptive mechanisms between reproductive costs and benefits in mammals affects parental investment through biases in sex ratio. Deer might be likely to show an early detection of climate variability because conception takes place in early autumn, but the main raising cost in deer concerns lactation, which takes place at the end of the following spring. The aim of this paper is to assess whether there is a relationship between global indices of climate variability such as El Niño-Southern Oscillation (ENSO) and sex ratio of a captive population of deer. Results showed that there was a negative correlation (r=−0.65) between sex ratio and ENSO indices between 1996 and 2008. El Niño enhances drier conditions during the summer in the Iberia Peninsula, which in turn favours a female bias. Results also suggest that the mechanism of early detection of climate variability exerts a strong effect on female reproductive physiology because the long-term stability of food resources in our setting has not markedly reduced it.

4

Effect of feeding regimes on growth, within-group weight variability, and chemical composition of the juvenile zander, Sander lucioperca [L.], body

84%

Zakes Z. , Szkudlarek M. , Wozniak M. , Demska-Zakes K. , Czerniak S.

Electronic Journal of Polish Agricultural Universities. Series Fisheries

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2003

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tom 06

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nr 1

EN

The study was aimed at determining effects of feed ration on growth, within-group variability, and chemical composition of the body of juvenile zander (c. 25 g initial individual weight) grown out in a recirculation system for 42 days. The fish were fed a commercial pelleted trout feed offered at three rations (Group L: 1.2% of stock biomass; Group M: 1.6% of stock biomass; and Group H: 2.0% of stock biomass). Each experimental treatment involved two replicates. The feed rations used were found to significantly (p < 0.01) affect fish growth: the mean body weight on termination of the experiment was 47.9, 60.3, and 69.4 g in Group L, M, and H, respectively. Statistically significant differences were revealed also in SGR and fish condition. The most favourable food conversion ratio (FCR) and protein efficiency ratio (PER) were found in Group M, the between-group differences being significant as well (p < 0.05).

5

Fur animal health - current status

84%

Henriksen P.

Zeszyty Naukowe. Przegląd Hodowlany

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1996

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tom 27