A trial was conducted to evaluate the effect of in ovo injection of prebiotic and synbiotics on growth performance, meat quality traits (cholesterol content, intramuscular collagen properties, fiber measurements), and the presence of histopathological changes in the pectoral muscle (PS) of broiler chickens. On d 12 of incubation, 480 eggs were randomly divided into 5 experimental groups treated with different bioactives, in ovo injected: C, control with physiological saline; T1 with 1.9 mg of raffinose family oligosaccharides; T2 and T3 with 1.9 mg of raffinose family oligosaccharides enriched with different probiotic bacteria, specifically 1,000 cfu of Lactococcus lactis ssp. lactis SL1 and Lactococcus lactis ssp. cremoris IBB SC1, respectively; T4 with commercially available synbiotic Duolac, containing 500 cfu of both Lactobacillus acidophilus and Streptococcus faecium with the addition of lactose (0.001 mg/embryo). Among the hatched chickens, 60 males were randomly chosen (12 birds for each group) and were grown to 42 d in collective cages (n = 3 birds in each 4 cages: replications for experimental groups). Broilers were fed ad libitum commercial diets according to age. In ovo prebiotic and synbiotic administration had a low effect on investigated traits, but depend on the kind of bioactives administered. Commercial synbiotic treatment (T4) reduced carcass yield percentage, and the feed conversion ratio was higher in T3 and T4 groups compared with other groups. The abdominal fat, the ultimate pH, and cholesterol of the PS were not affected by treatment. Broiler chickens of the treated groups with both slightly greater PS and fiber diameter had a significantly lower amount of collagen. The greater thickness of muscle fibers (not significant) and the lower fiber density (statistically significant), observed in treated birds in comparison with those of the C group, are not associated with histopathological changes in the PS of broilers. The incidence of histopathological changes in broiler chickens from examined groups was low, which did not affect the deterioration of meat quality obtained from these birds.

BackgroundAmong various feed additives currently used in poultry nutrition, an important role is played by bioactive substances, including prebiotics. The beneficial effect of these bioactive substances on the gastrointestinal tract and immune system give rise to improvements in broiler health and performance nutrition, thus increasing the productivity of these birds. An innovative method for introducing bioactive substances into chickens is the in ovo injection into eggs intended for hatching. The aim of the study was to evaluate the development of histomorphological parameters of the duodenum and productivity in chickens injected in ovo with the prebiotic DiNovo® (extract of Laminaria species of seaweed, BioAtlantis Ltd., Ireland) on d 12 of incubation, under large - scale, high density poultry production conditions.ResultsThere was no significant impact of the injection of DiNovo® prebiotic on the production parameters of broiler chickens (body weight, FCR, EBI and mortality) obtained on d 42 of rearing. No significant impact of the DiNovo® injection on the duodenum weight and length was observed, as well as on the CSA, diameter and muscular layer thickness of the duodenum. The in ovo injection of DiNovo® significantly increased the width of the duodenal villi (P < 0.05) and crypt depth (P < 0.01) of chickens on d 21 of rearing. Other histomorphological parameters of duodenal villi at d 42 of chickens rearing such as: the height, width, and cross section area of villi were significantly greater in chickens from the control group compared to those from the DiNovo® group (P < 0.05 and P < 0.01).ConclusionsIn conclusion, this study demonstrates that injection of DiNovo® prebiotic into the air chamber of egg significantly influences the histomorphological parameters on d 21 of rearing without negatively affecting productivity in chickens at the end of rearing.

Due to selection for increased body weight modern broilers are 3-4 times heavier as compared with chickens of the laying type. The muscle mass is mainly determined by the total number of muscle fibres (hyperplasia), their thickness (hypertrophy) and different fibre types. Hyperplasia occurs during either embryogenesis or the early posthatching period. Skeletal muscles originate from the dermatomyotome, which differentiates into four myogenic cell populations: myotomal cells, embryonic myoblasts, fetal myoblasts and satellite cells; the latter are the adult myoblasts, present within adult skeletal muscles to serve as a cell source for both muscle regeneration and self-renewal. Pax3 keeps migrated precursor cells non-differentiated, thereby controlling transcription of the MyoD gene, whereas Pax7 is a significant regulator of the satellite cell population. Manipulation of temperature and light quality and quantity have been proposed as methods of both pre-and postnatal myogenesis stimulation. Being thermogenic stimulants, both thyroid and adrenal hormones substantially stimulate metabolism. Shortterm exposure of embryos to increased temperature between days 16 and 18 of incubation directly influences the proliferation and differentiation of muscle fibres, which manifest themselves in increased hyperplasia. Ultraviolet radiation is an effective means for disinfection of hatching eggs, resulting in a change of embryonic mortality rate during breeding. Especially, green light influences both body weight and the satellite cell number in the first days posthatch, thereby enhancing the growth of embryos, and causing a significant increase in both muscle and body weight. In ovo green stimulation probably enhances the proliferation and differentiation of myoblasts, subsequently causing an increase in muscle weight. The present paper highlights the possibilities of enhancing growth and development of skeletal muscles in birds by manipulation of many aspects of their regulation, thereby contributing to a further increase in production efficiency.

Effects of prebiotics and synbiotics delivered in ovo on broiler small intestine histomorphology during the first days after hatching. Folia Biologica (Kraków) 64: 131-143. The objective of the study was to determine the effect of prebiotics and synbiotics administered in ovo on the 12 th day of incubation, on the development of the intestinal villi and the number of goblet cells in the small intestine of broiler chickens on the 1 st and the 4 th days of life of chicks. Two prebiotics: inulin (PI) or Bi 2 tos (PB) and two synbiotics: inulin + L. lactis subsp. lactis (SI) or Bi 2 tos + L. lactis subsp. cremoris (SB) were injected in ovo on the 12 th day of embryonic development. The control group of the embryos was injected with physiological saline (C). On the 1 st day of life, an increase in the height of the villi in the jejunum was reported as a result of the injection of pre-and synbiotics, moreover an increase in the surface area of the villi in the jejunum and the duodenum in chicks from the SB group was also observed. A stimulatory effect of synbiotics on the morphology of the duodenum and the jejunum was also observed on the 4 th day after hatching. Conversely, in the ileum, in the SB group, a reduction in the height of villi was found both on the 1 st and the 4 th days of life. In contrast, injection of inulin and synbiotic with the addition of inulin resulted in an increase in the number of goblet cells in the duodenum and the jejunum on the 1 st day of life, and caused a significant decrease on the 4 th day after hatching.