69 research outputs found
Nutritional strategies and management practices to improve poultry meat quality
No full textThe estimated growth in world population is increasing global food demand,
particularly of protein. From a historical perspective, meat has represented
the main protein source for humans, contributing to biosocial well-being
and sustenance (Leroy and Praet, 2015; Leroy and De Smet, 2019). Among
the different types of meat, poultry meat has experienced a significant
production increase in the past 50 years, and future forecasts seem to confirm
that the same trend will be observed in the next decade (Windhorst, 2017).
Many factors have contributed to the universal appreciation of poultry meat,
including its affordability, nutritional and sensory properties, versatility and
ease of preparation as well as the absence of religious limitations related to
its consumption (Baldi et al., 2020). In addition, poultry meat production is
considered relatively efficient and sustainable in terms of resources utilization
and environmental impact, which are crucial aspects for fulfilling the increasing
protein demand in an efficient and sustainable way (Zampiga et al., 2021a). Modern consumers are increasingly aware of the nutritional value and
quality traits of foods, with special regard to the importance of high-quality
protein for healthy life and well-being. Poultry meat is generally recognized
as ‘healthy’ mostly because of its nutritional profile which is characterized
by high protein, low fat and cholesterol content and balanced ω-6/ω-3
polyunsaturated fatty acid (PUFA) ratio (Petracci et al., 2015). Poultry meat
quality could be influenced by both genetic (e.g. bird genetic background
and metabolic features) and environmental related factors (e.g. nutrition,
management and microclimatic conditions) as well as their interaction. Among
the environmental factors, nutrition has been extensively regarded as one
of the most important determinants of poultry meat quality, being able to
induce changes in the proximate composition and technological properties
of poultry meat (Cavani et al., 2009). Furthermore, other factors such as bird
exposure to high environmental temperatures or castration (technically called
‘caponization’ in chickens) were associated with significant modifications of
meat quality traits (Calik, 2014; Zaboli et al., 2019). The aim of this chapter
is, therefore, to summarize the most relevant findings concerning the effects
of nutrition and feeding strategies on the different facets of the meat quality
concept as well as to discuss the consequences of some environmental and
management factors, such as heat stress and caponization, on this crucial topic
for the modern poultry industry
Effects of genotype and age on eggshell cuticle coverage and color profile in modern laying hen strains
No full textThe aim of this research was to investigate the effects of laying hen genotype and age on eggshell cuticle deposition. A total of 4,320 brown eggs were obtained from 3 modern hen strains (A, B, and C), currently used worldwide for commercial egg production, at different intervals of age (20–30, 40–50, and 60–70 wk). Four samplings of 120 randomly collected eggs were carried out for each genotype/interval of age. Eggs were individually weighed and cuticle blue staining was used to assess quality and degree of cuticle coverage. On each egg, the eggshell color profile was assessed before and after staining using the CIE L*a*b* system and these values were used to calculate ΔE*ab. A 4-point scale visual score (VS) system was also applied to estimate the degree of cuticle coverage after staining (0 = no coverage, 1 = partial coverage, 2 = total coverage - low degree, 3 = total coverage - high degree). The effects of genotype and age and their interaction on eggshell color attributes were assessed by means of factorial ANOVA, while omnibus Chi-Square and Chi-squared Automatic Interaction Detector algorithm were applied for the analysis of VS data. Overall, both genotype and age affected the eggshell color profile as well as the degree of cuticle coverage. Hen strain A showed better cuticle deposition in comparison with B and particularly C one, being ΔE*ab values significantly higher. The VS evaluation revealed that eggs with impaired cuticle coverage degree increased with the hen age (23, 34, and 37%, respectively for 20–30, 40–50, and 60–70 wk; P < 0.05). However, a significant interaction between genotype and age was observed: transition from early to late hen age resulted in a significantly different pattern of ΔE*ab changes in each genotype. The classification tree analysis confirmed that the hen genotype has a greater effect than the age on cuticle deposition. In conclusion, considering the importance of the cuticle in table egg production, these results highlight the crucial role exerted by the genotype on eggshell cuticle coverage
Importance of feed efficiency for sustainable intensification of chicken meat production: implications and role for amino acids, feed enzymes and organic trace minerals
No full textBroiler chicken production is expected to increase significantly in the next decades to satisfy the poultry meat demand of a growing world population. In this scenario, one of the most important challenges for the poultry industry is to enhance bird productivity while remaining economically and environmentally sustainable. Feeding represents the major cost in raising of broiler chickens and has important implications for environmental impact, either directly or indirectly. Therefore, improving broiler capacity in converting ingested feed into body growth, which is generally referredto as feed efficiency (often expressed through the feed conversion ratio), is fundamental to promoting a sustainable intensification of poultry production. In this review, we highlight the importance of feed efficiency improvements in terms of overall sustainability for the broiler chicken production chain. Furthermore, the potential of feed additive-based nutritional strategies, such as the dietary
administration of crystalline amino acids, proteases, phytases and organic minerals, is critically discussed in the light of their role in supporting the sustainable intensification of this crucial livestock sector
Effect of different arginine-to-lysine ratios in broiler chicken diets on the occurrence of breast myopathies and meat quality attributes
No full textThis study was carried out to evaluate the effect of different digestible arginine-to-lysine (dig Arg:Lys) ratio in broiler diets on the occurrence of breast myopathies, productivity, and meat quality traits. A total of 1,755 1-day-old Ross 308 male chicks was randomly divided in 3 experimental groups (9 replications/group): CON, fed a 4 feeding-phases commercial diet (dig Arg:Lys ratio = 1.05, 1.05, 1.06, 1.07, respectively in starter, grower I, grower II and finisher phase), and ARG2 and ARG3 groups fed CON diet supplemented respectively with 20 and 30% higher levels of crystalline L-arginine (dig Arg:Lys ratio = 1.25, 1.25, 1.26, 1.27 and 1.35, 1.35, 1.36, 1.37, respectively). Productive performance was recorded throughout the rearing cycle. At processing (43 d), breasts (n = 150/group) were randomly collected to evaluate the incidence and severity of white striping (WS), wooden breast (WB), and spaghetti meat (SM) defects (3- points scale).Meat quality traits, such as color, pH, drip and cook losses, marinade performances, and proximate composition were determined on 12 fillets/group. Although productive performance and meat quality traits resulted not significantly affected, the occurrence of some breast myopathies was modified by the dietary treatments. ARG2 and ARG3 exhibited a significantly higher percentage of breast without WS compared to CON (28 and 41 vs. 17%, respectively; P < 0.001). ARG3 reported the lowest percentage of breasts with severe WS (11 vs. 27 and 31%, respectively for ARG3, ARG2, and CON; P < 0.001) and the highest of those showing no SM abnormality (81 vs. 69 and 65%, respectively for ARG3, ARG2, and CON; P < 0.01). Furthermore, a numerical reduction of breasts with severe WB was observed in ARG3 (12 vs. 25 and 19%, respectively for ARG3, ARG2, and CON; P = 0.12). In conclusion, the dietary supplementation of arginine to increase the dig Arg:Lys ratio by about 30% in respect to the current recommendations for broiler chickens has positive implications on the occurrence of some breast meat abnormalities
Effect of chronic heat stress on gastrointestinal histology and expression of feed intake-regulatory hormones in broiler chickens
No full textHeat stress (HS) dramatically impairs the growth performance of broiler chickens, mainly as a consequence of reduced feed intake due to the loss of appetite. This study was aimed at evaluating the alterations induced by chronic HS conditions on the morphological and morphometric features of the gastrointestinal (GI) tract and on the expression of some enteroendocrine cells (EECs) involved in the regulation of feed intake in chickens. Three hundred male chickens (Ross 308) were divided into two experimental groups and raised either in thermoneutral environment for the whole fattening period (0-41 days) (TNT group) or subjected to chronic HS conditions (30 degrees C for 24 h/day) from 35 to 41 days (HS group). Samples of proventriculus, duodenum, jejunum and cecum were collected from 24 broilers (12/group). Haematoxylin-eosin was used for the morphometric evaluations, while immunohistochemistry was applied for the evaluation of EECs expressing ghrelin (GHR), cholecystokinin (CCK), neuropeptide Y (NPY), glucagon-like peptide-1 (GLP-1), and serotonin (5-HT). In the proventriculus, HS reduced total wall thickness and mucous layer height (P <= 0.01) as well as mean diameter, circumference, and area of the compound tubular glands (P <= 0.001) with respect to TNT. The small intestine of HS birds was characterised by decreased villous height and total thickness (duodenum, P <= 0.01; jejunum, P <= 0.001), whereas crypt depth and width were reduced only in the jejunum (P <= 0.01). HS had negligible effects on the morphological aspects of the cecum. In the proventriculus, an increase in GHR and NPY EECs was observed in response to HS (P <= 0.001). Similarly, the small intestine villi of the HS group showed greater GLP-1 (P <= 0.05), 5-HT (P <= 0.001) and CCK (P <= 0.01) EECs. Moreover, the expression of 5-HT EECs was higher in the duodenal (P <= 0.01) and jejunal (P <= 0.01) crypts of HS birds, whereas GLP-1 and CCK EECs increased only in jejunal crypts (P <= 0.05). Finally, 5-HT EEC expression was increased in the cecum of HS group (P <= 0.01). In conclusion, these outcomes demonstrate that chronic HS induces morphometric alterations not only in the small intestine but also in a key organ such as the proventriculus. Furthermore, HS conditions affect the presence and distribution of EECs, suggesting that some GI peptides and biogenic amine may be implicated in the regulation of appetite and voluntary feed intake in heat-stressed broiler chickens. (C) 2022 The Authors. Published by Elsevier B.V. on behalf of The Animal Consortium
Effect of EU electrical stunning conditions on breast meat quality of broiler chickens
No full textElectrical stunning is still the main method used worldwide in commercial poultry plants. The stunning procedures in water bath affect both bird welfare and meat quality attributes. The European Union (EU) Council Regulation 1099/2009 on the protection of the animal at the time of killing established the minimum current flow through individual bird at a specified frequency to assure an effective stun that must last until the bird death. The aim of this study was to compare the effect of the application of different stunning current flows on the incidence of hemorrhages (classified as 1=no lesion, 2=moderate and 3=severe lesion) and some quality traits (pHu, color, drip and cooking losses, and shear force) of chicken breast meat. A total of 12 flocks of broiler chickens, each equally divided into light, medium and heavy-size, were submitted either to the stunning condition usually adopted before the entry into force of the current EU Regulation (90 mA/bird, 400 Hz) (OLD) or to that enforced by it (150 mA/bird, 400 Hz) (NEW). Overall, the incidence of severe hemorrhages dramatically increased in NEW group in comparison with OLD one (55 vs. 27%; P<0.001) and particularly in heavy-size birds (72 vs. 25%; P<0.001). In general, meat quality attributes were not affected by the stunning conditions with the exception of drip loss that resulted lower in NEW than OLD birds (1.01 vs. 1.27; P<0.001). In conclusion, the adoption of a higher current flow, as suggested by the EU regulation to protect animal at the time of killing, increases the incidence of breast hemorrhages while maintaining meat quality traits with possible beneficial effect on water holding capacity of fresh meat
Variability and interaction of some egg physical and eggshell quality attributes during the entire laying hen cycle
No full textThe aim of this study was to investigate the variability and relationships between some egg physical (egg weight, width, length, shape index and surface area) and eggshell parameters (weight and percentage, thickness, breaking strength, L*, a*, and b* values) during the entire laying hen cycle. A total of 8,000 eggs was collected every 5 weeks, from 30 to 81 weeks of hens age (10 samplings of 400 eggs/house), in 2 identical poultry houses equipped with enriched cages. For the statistical analysis, ANOVA, Bivariate Correlation, Principal Component Analysis (PCA) and hierarchical cluster analysis were used. An increase of egg weight, length and eggshell lightness (L*) associated with a reduction of eggshell percentage, breaking strength, and redness (a*) was observed as the hen aged (P<0.05). Overall, the coefficients of variation resulted <5% in width, length, shape index, and egg surface area; from 5 to 10% of egg weight, shell weight, shell percentage, shell thickness, L*, and b*; >10% of eggshell breaking strength and a*. According to the PCA, the highest changes during the laying cycle are related to egg physical parameters (32%) and to eggshell breaking strength, percentage, and thickness (26%). The egg physical parameters appeared to be strongly correlated to each other, whereas a slight correlation between eggshell breaking strength and color attributes were evidenced (-0.231 and 0.289 respectively for L* and a*; P<0.01). Hierarchical cluster analysis, based on principal components of the overall egg attributes is hereby considered, evidenced dissimilarities for eggs laid from peak production up for 39 weeks of hen age from the eggs laid afterwards. The latter group could also be divided into two subgroups, one comprising eggs laid from 44 and 53 weeks of hen age and the other from 58 weeks to the end. In conclusion, the large dataset created in this study allowed to extrapolate some robust information regarding the variability and correlations of the egg physical and eggshell quality attributes throughout the entire laying hen cycle
Differences in productive performance and intestinal transcriptomic profile in two modern fast-growing chicken hybrids
No full textThis study aimed to characterize growth performance and ileum transcriptomic profile of two fast-growing chicken hybrids (HA and HB). A total of 1,170 one-day-old female chicks (n = 585 per genotype) were weighed and randomly divided into 18 pens (9 replications/group). Both the groups received the same commercial diet (starter, 0–9 days; grower I, 10–21 days; grower II, 22–34 days; and finisher, 35–43 days). Body weight (BW), daily feed intake (DFI) and feed conversion ratio (FCR) were determined on a pen basis at the end of each feeding phase. At the processing (43 days), incidence of footpad dermatitis (FPD) was evaluated on all the birds and ileum mucosa was collected from 1 bird/replication. Total mRNA was extracted to perform microarray analysis (Chicken Gene 1.1ST Array Strip), and an exploratory pathway analysis was then conducted (Gene Set Enrichment Analysis software). The two genotypes showed different growth patterns throughout the study. HA birds exhibited higher BW and better FCR than HB after 9 days (228 vs. 217 g and 1.352 vs. 1.419, respectively, p < 0.05). At 21, 34 and 43 days, HB birds reported higher BW (807 vs. 772 g; 1,930 vs. 1,857 g and 2,734 vs. 2,607 g, respectively; p < 0.01), DFI (74.9 vs. 70.6 g bird−1 day−1, p < 0.01; 144.4 vs. 139.6 g bird−1 day−1, p = 0.06; and 196.5 vs. 182.4 g bird−1 day−1, p < 0.01) and similar FCR compared to HA ones. HB group showed a higher percentage of birds with no FPD (75% vs. 48%; p < 0.001). Transcriptomic analysis revealed enriched gene sets for mitochondria, cellular energy metabolism, and cell structure and integrity in ileum mucosa of HA broilers and enriched gene sets for immune system activation, cell signalling and inflammation in HB ones. In conclusion, these results indicated that the two chicken genotypes are characterized by different growth patterns, feeding behaviour and gene expression profiles in the intestinal mucosa
Orexin system is expressed in avian liver and regulates hepatic lipogenesis via ERK1/2 activation.
No full textOrexins are originally characterized as orexigenic hypothalamic neuropeptides in mammals. Subsequent studies found orexin to be expressed and perform pleiotropic functions in multiple tissues in mammals. In avian (non-mammalian) species, however, orexin seemed to not affect feeding behavior and its physiological roles are poorly understood. Here, we provide evidence that orexin and its related receptors are expressed in chicken hepatocytes. Double immunofluorescence staining showed that orexin is localized in the ER, Golgi, and in the lysosomes in LMH cells. Brefeldin A treatment reduced orexin levels in the culture media, but increased it in the cell lysates. Administration of recombinant orexins upregulated the expression of orexin system in the liver of 9-day old chicks, but did not affect feed intake. Recombinant orexins increased fatty acid synthase (FASN) protein levels in chicken liver, activated acetyl-CoA carboxylase (ACCα), and increased FASN, ATP citrate lyase(ACLY), and malic enzyme (ME) protein expression in LMH cells. Blockade ERK1/2 activation by PD98059 attenuated these stimulating effects of orexin on lipogenic factors. Overexpression of ERK1/2 increased the expression of lipogenic genes, and orexin treatment induced the phosphorylated levels of ERK1/2Thr202/Tyr204, but not that of p38 Thr180/Tyr182 or JNK1/2 Thr183/Tyr185 in chicken liver and LMH cells. Taken together, this is the first report evidencing that orexin is expressed and secreted from chicken hepatocytes, and that orexin induced hepatic lipogenesis via activation of ERK1/2 signaling pathway
Neuropeptide Y and its receptors are expressed in chicken skeletal muscle and regulate mitochondrial function.
No full textNeuropeptide Y (NPY) is a highly conserved 36-amino acid neurotransmitter, which is primarily expressed in themammalian arcuate nucleus of the hypothalamus. It is a potent orexigenic neuropeptide, stimulating appetite and inducing feed intake in a variety of species. Recent research has shown that NPY and its receptors can be expressed by peripheral tissues, but their role is not yet well defined. Specifically, this information is particularly sparse in avian species. Therefore, the aim of this study was to determine the expression of NPY and its receptors, and determine their regulation by environmental and nutritional stressors, in the skeletal muscle of avian species using in vivo and in vitro approaches. Here, we show that NPY and its receptors are expressed in chicken breast and leg muscle as well as in quail myoblast (QM7) cell line. Intraperitoneal injection of recombinant NPY increased feed intake in 9-d old chicks and upregulated the expression of NPY and NPY receptors in breast and leg muscle, suggesting autocrine and/or paracrine roles for NPY. Additionally, NPY is able to modulate the mitochondrial network. In breast muscle, a low dose of NPY upregulated (P < 0.05) the expression of genes involved in ATP production (uncoupling protein, UCP; nuclear factor erythroid 2 like 2, NFE2L2) and dynamics (mitofusin 1, MFN1), while a high dose decreased (P < 0.05) markers of mitochondrial dynamics (mitofusin 2, MFN2; OPA1 mitochondrial dynamin like GTPase, OPA1) and increased (P < 0.05) genes involved in mitochondrial biogenesis (D-loop, peroxisome proliferator activated receptor gamma, PPARG). In leg muscle, NPY decreased (P < 0.05) markers of mitochondrial biogenesis and ATP synthesis (D-loop; peroxisome proliferator activated receptor alpha, PCG1A; peroxisome proliferator-activated receptor gamma, coactivator 1 beta, PPARGC1B; PPARG; NFE2L2). In QM7 cells, genes associated with mitochondrial biogenesis, dynamics, and ATP synthesis were all upregulated (P < 0.05), even though basal respiration and ATP production were decreased (P < 0.05) with NPY treatment as measured by XF Flux analysis. Together, these data show that the NPY system is expressed in avian skeletal muscle and plays a role in mitochondrial function
- …
