A conventional hatchery vs "on-farm" hatching of broiler chickens in terms of microbiological and microclimatic conditions.

"On-farm hatching" is one of the proposed alternatives to conventional hatchery-hatching. This solution reduces distress and improves the welfare of the chicks around the hatching period. Therefore, it seemed interesting to compare conventional hatchery and "on-farm" hatching in terms of microbiological and microclimatic conditions. Hatching eggs (Ross 308) were incubated in a commercial hatchery. The control group (HH, 683 eggs) hatched in a conventional hatcher, while the other eggs were transported into the experimental chicken-hall for on-farm hatching, and set in pens directly on litter (OL, 667 eggs) or plastic trays (OT, 678 eggs). One-day-old chicks were also placed in the experimental hall. Microclimatic parameters were controlled every 12 h. The microbiological status of the surface of the eggshells and the litter was assessed based on the total number of aerobic mesophilic microorganisms and also the selected individual genus/species of bacteria. The hatchability of HH was 96.4% in comparison to 93.9% and 95.8% for OL and OT, respectively (P > 0.05). On the other hand, 2.1% of the HH chicks were found injured/dead, while only 0.2-0.3% of the on-farm groups were. The total number of aerobic mesophilic microflora on the surface of as-hatched shells was 4.93 ± 0.629 log CFU/g in HH, while only 1.14 ± 0.995 and 1.93 ± 1.709 log CFU/g in OL and OT, respectively (P < 0.001). Similarly, the total count of bacteria in the litter in the on-farm hatched pens was 1.9-fold lower than in pens set with HH chicks (P < 0.001). In summary, on-farm hatching results in hatchability that is no worse than in a conventional hatcher, while the microbiological status of as-hatched eggshells and litter is significantly better. Therefore, on-farm hatching seems to provide appropriate environmental conditions for newly hatched chicks and poses no epizootic risk.

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.