Effect of age of Japanese quail on physical and biochemical characteristics of eggs

The aim of the study was to investigate the effects of age of birds on egg quality in Japanese quail. The eggs were randomly selected from among all eggs laid on the same day when the birds were 15, 23 and 31 weeks old. At each time point, 90 fresh eggs were evaluated for their physical and biochemical characteristics. Egg weights were similar over time. At 23 and 31 weeks, the eggs had less shell than at 15 weeks. Crude fat and ash contents of the eggs increased with the age of the birds. Crude protein was also highest in eggs of the oldest quail. At 31 weeks old, the eggs were lowest in pH of yolk and white. Quail that were 23 and 31 weeks old laid eggs with significantly higher polyunsaturated fatty acid (PUFA) and lower saturated fatty acid (SFA) contents. The lowest cholesterol content was in egg yolks from 23-week-old quail. The oldest birds had the highest contents of sodium, potassium, zinc, selenium, copper, and manganese. The content and activity of lysozyme decreased with ageing of the birds. From the consumers’ point of view, eggs from older birds appeared to be the most valuable. At the same time, as the quail ages, the antibacterial properties of eggs deteriorate, which may indicate a shorter shelf life

Utilization of selected organic acids and their mixtures in feeding of broiler chickens

Celem przeprowadzonych badań było określenie wpływu dodatku średniołańcuchowych kwasów tłuszczowych (MCFA), maślanu wapnia, kwasu benzoesowego i ich mieszanin, jako potencjalnych stymulatorów wzrostu w żywieniu kurcząt rzeźnych. Doświadczenie przeprowadzono na 12 grupach ptaków żywionych dietami zawierającymi dodatek kwasu benzoesowego – B (0,1%), maślanu wapnia – MW (1%), średniołańcuchowych kwasów tłuszczowych (MCFA): kapronowego – K1 (0,85%), kaprylowego – K2 (0,85%), kaprynowego – K3 (0,85%), ich mieszaniny w stosunku 1:1:1 – MCFA (0,85%) oraz mieszaniny kwasu kaprynowego i kaprylowego w formie triglicerydowej (0,3%) w stosunku 1,4:1 – MCT. Grupa kontrolna pozytywna (PC) zawierała dodatek kokcydiostatyku – salinomycyny, w ilości 70 mg/kg. W grupie kontrolnej negatywnej (NC) nie zastosowano żadnych dodatków. We wszystkich okresach odchowu nie stwierdzono poprawienia wskaźników odchowu w stosunku do PC i NC (P<0,05). W okresie od 1. do 14. dnia życia najgorszym przyrostem charakteryzowały się grupy BK2 i BMCFA, natomiast najwyższy współczynnik zużycia paszy na 1 kg m.c. występował w grupie BMW (P<0,05). W okresie od 15. do 35. dnia życia najgorszym przyrostem i zużyciem paszy na 1 kg przyrostu charakteryzowały się ptaki z grupy MWMCFA (P<0,05). W przypadku grup BMCFA, BMCT i BMW również stwierdzono wzrost współczynnika zużycia paszy (P<0,05). W całym okresie doświadczenia (do 35. dnia życia) pogorszenie przyrostów masy ciała ptaków stwierdzono w grupie BMCFA, natomiast negatywny wpływ dodatków na współczynniki zużycia paszy występował w przypadku grup BMW, BMCT, BMCFA oraz MWMCFA (P<0,05).The aim of this study was to determine the effect of medium chain fatty acids (MCFA), calcium butyrate, benzoic acid and their mixtures as potential growth promoters in feed for broiler chickens. The experiment was conducted on 12 groups of birds fed with the diets containing the addition of benzoic acid – B (0.1%), calcium butyrate – MW (1%), medium-fatty acids (MCFA): caproic – K1 (0.85%), caprylic – K2 (0.85%), capric – K3, and their mixtures (0.85%) in the ratio 1:1:1 – MCFA and the mixture of capric and caprylic acid in a form of triglycerides (0.3%) in the ratio 1.4:1 – MCT. The positive control (PC) included addition of a coccidiostatic – salinomycin in the quantity of 70 mg/kg. The negative control (NC) did not contain any additives. In all periods of rearing, no improvement in performance results were observed in relation to PC and NC (P<0.05). In the period from 0 to 14 days, groups BK2 and BMCFA were characterized by the worst body weight gains, while the highest feed conversion ratio (FCR) was recorded in group BMW (P<0.05). In the period from 15 to 35 days, the birds from group MWMCFA were characterized by the worst growth and the worst FCR (P<0.05). In the case of BMCFA, BMCT and BMW groups, FCR was high (P<0.05). During the entire period of the experiment (1-35 days), the deterioration in body weight gains of the birds was observed in group BMCFA, while the birds from BMW , BMCT, BMCFA and MWMCFA groups were characterized by negative effects of experimental additives (P<0.05) on feed conversion ratio

Effect of medium chain fatty acids (MCFA) on growth performance and nutrient utilization in broiler chickens

Celem przeprowadzonych badań było określenie wpływu dodatku średniołańcuchowych kwasów tłuszczowych jako potencjalnych stymulatorów wzrostu w żywieniu kurcząt rzeźnych. Doświadczenie przeprowadzono na 6 grupach ptaków, żywionych dietami z takim samym udziałem (0,85%) kwasu kapronowego, kaprylowego i kaprynowego oraz ich mieszaniny (33:33:33%). Pozostałe dwie grupy były kontrolne (negatywa, pozytywna). W grupie kontrolnej pozytywnej dieta zawierała dodatek kokcydiostatyku – salinomycyny, w ilości 70 mg/kg. W okresie od 1. do 35. dnia odchowu kwas kaprynowy wpłynął na zmniejszenie pobrania paszy przy jednoczesnym pogorszeniu przyrostów masy ciała kurcząt, w porównaniu do grupy kontrolnej pozytywnej, oraz polepszenie współczynnika konwersji paszy w okresie od 15. do 35. dnia i od 1. do 35. dnia w porównaniu do grupy kontrolnej negatywnej (P≤0,05). W przypadku kwasu kaprylowego i mieszaniny trzech kwasów organicznych stwierdzono identyczne statystyczne zależności odpowiadające grupie z dodatkiem salinomycyny we wszystkich okresach trwania doświadczenia (P≤0,05). Natomiast u kurcząt żywionych mieszanką z dodatkiem kwasu kapronowego stwierdzono pogorszenie współczynnika konwersji paszy, zarówno w okresie od 15. do 35. dnia, jak i od 1. do 35. dnia (P≤0,05). W przypadku innych parametrów nie stwierdzono statystycznie istotnych zależności (P≤0,05).The aim of this study was to determine the effect of medium chain fatty acids as potential growth promoters in feeding of broiler chickens. The experiment was conducted on 6 groups of birds fed the diets with the same proportions (0.85%) of caproic, caprylic and capric acids and their mixture (33:33:33%). The remaining two groups were controls (negative, positive). The positive control included an addition of coccidiostatic – salinomycin in the amount of 70 mg/kg. In the period from 1 to 35 days, capric acid resulted in reduction of feed intake and lower weight gain of chickens in comparison with the positive control and the improvement of feed conversion ratio in the periods from 15 to 35 and from 1 to 35 days of life in comparison with the negative control (P≤0.05). In the case of the caprylic acid and a mixture of three organic acids, identical statistical relations were observed in all periods of the experiment in the group supplemented with salinomycin (P≤0.05). In chickens fed the diets with caproic acid, deterioration of the feed conversion ratio in the period from 15 to 35 days and from 0 to 35 days of life was recorded (P≤0.05). No statistically significant correlations were found for other experimental parameters (P≤0.05)

Effect of weight and storage time of broiler breeders’ eggs on morphology and biochemical features of eggs, embryogenesis, hatchability, and chick quality

The transfer of hatchability results obtained under experimental conditions to the commercial ground with a positive financial effect proves the value and usefulness of these data. On the other hand, finding results on commercial processes of broiler breeders’ egg incubation in the literature is challenging. The presented study aimed to determine the effects of egg weight and storage time on the physical, biochemical characteristics of hatching eggs, embryogenesis and hatchability in Ross 308 broiler breeders. On the laying day, the eggs were divided into four weight groups: S – small eggs (57–61 g), M – medium eggs (62–66 g), L – large eggs (67–71 g), and XL – extra-large eggs (72–76 g). The eggs were then stored for 3, 7, 14, and 21 days under controlled conditions. As the egg storage time increased, a decrease in the yolk quality (lower index) was observed. The highest Haugh units were found in eggs from the S and M groups. The cholesterol content of the M, L, and XL groups was lower on days 7, 14, and 21 as compared to that of eggs only stored for 3 days. Egg weight loss during incubation decreased with an increase in the egg weight. An extension of the egg storage time caused an increase in the loss of egg weight. On the 14th and 18th days of hatching, an increase in the eggshell temperature was noted with an increase in the weight of the egg. The eggs stored for 7 days were characterised by the highest shell temperature on each day. The highest hatchability percentage was recorded for the M group. The hatchability rate decreased with the prolongation of the storage time, while the number of crippled chicks after hatching increased. The results confirmed that the increased weight of the eggs and prolonged storage time (14 and 21 days) increased the weight and decreased the length of the newly hatched chicks, respectively. Chicks from the heaviest eggs and those stored for 14 and 21 days showed poor results on the Pasgar score® test. The observations indicate the need to adopt various (of those available) methods to assess the quality of newly hatched chicks in hatcheries in order to produce high-quality broiler chickens. The results also indicate that prolonged egg storing beyond 14 days may affect the thyroid hormone economy during the hatching of chicks, especially in the XL group