Flock Uniformity Research Articles

Linking gastrointestinal tract structure, function, and gene expression signatures to growth variability in broilers: a novel interpretation for flock uniformity

Variation in body weight (BW) within broiler flocks is a significant challenge in poultry production. Investigating differences in gut-related parameters between low (LBW) and high BW (HBW) chicks may provide insights into the underlying causes of BW heterogeneity. 908 day-old male broiler chicks were reared until d 7 and then ranked into LBW and HBW groups. Thereafter, performance parameters were compared between BW groups periodically. On d 7, 14, and 38, visceral organ characteristics, intestinal permeability, and duodenal and ileal histomorphology were examined. Expression profiles were analyzed for 79 ileal genes related to gut barrier function, immune function, nutrient transport, gut hormones, nutrient receptors, metabolism, and oxidation using high-throughput qPCR. Student's t-tests were performed to compare measurements. Multivariate statistics, including partial least square regression (PLSR) analysis, were applied to identify combinations of key genes discriminating BW groups, offering predictive capability for phenotypic variations. The HBW group remained heavier at each timepoint, which could be explained by higher feed intake. The HBW group had shorter relative small intestine length but higher villus height and villi height/crypt depth ratios. The LBW group demonstrated increased intestinal permeability on d 38. The LBW group showed upregulation of immune response genes including TNF-α on d 7 and CYP450 on d 38, while the HBW group showed higher AHSA1 and HSPA4 expressions on d 7. The LBW group had upregulation of the metabolism genes mTOR and EIF4EBP1 on d 7 and the satiety-induced hormone cholecystokinin on d 14, while the HBW group tended to increase expression of the hunger hormone ghrelin on d 38. Genes related to gut barrier function, nutrient transport, and oxidation categories were consistently upregulated in the HBW group. PLSR models revealed 4, 12, and 11 sets of key genes highly predictive of BW phenotypes on d 7, 14, and 38, respectively. These findings suggest that growth rates are linked to the intestinal size, structure, and function of broiler chickens, offering insights into the underlying mechanisms regulating BW.

Are turkey hens affected by light flicker? Effects on performance and health

Light flicker is a commonly overlooked factor of artificial light sources. This study aimed to determine the impacts of light-flicker frequency on performance, general health, and mortality of 11-wk Nicholas Select turkey hens. The experiment consisted of 2 trials (block) in a randomized complete block design, with 3 light-flicker frequency treatments (30, 90, or 195 Hz). Turkeys (n = 364 per replicate) were randomly placed into environmentally controlled rooms (3 room replicates per treatment per trial). Group body weight (BW) and feed consumption were measured at 0, 4, 8, and 11 wk, and feed efficiency (mortality corrected feed-to-gain; F:Gm) was calculated for each period. Mortality and culls were collected twice daily. Flock uniformity, feather condition and cleanliness, footpad score, and mobility were evaluated at 10 wk (30 birds per room). Litter quality and ocular weight and dimensions were evaluated (11 wk; 4 birds per room). Data were analyzed using Proc Mixed (SAS 9.4) and significance was declared when P < 0.05. At 8 wk, BW was lower under 30 Hz compared to 195 Hz (P = 0.03). Feed consumption was lowest under 30 Hz (0-4 wk and 4-8 wk; P < 0.01). Mortality-corrected F:G was improved under 30 Hz for 8 to 11 wk and 0 to 11 wk (P = 0.05 and P = 0.04, respectively). Total mortality was lower under 195 Hz compared to 30 Hz (P = 0.02). Uniformity, gait score, feather condition, and litter quality were unaffected by flicker. Footpad scores were improved under 90 Hz (P = 0.01), leading to an improved average footpad score (P = 0.02). Feather cleanliness was improved under 90 Hz compared to both 30 Hz and 195 Hz (P<0.01). Right eyeball dimensions differed across lighting treatments, with the dorso-ventral diameter being larger in birds under 30 Hz compared to 195 Hz (P = 0.05). The anterior-posterior size also increased in birds under 30 Hz compared to 90 Hz (P = 0.03). Light flicker impacted turkey hens, with the results demonstrating negative impacts on early growth and changes to ocular characteristics.

Triticale: A General Overview of Its Use in Poultry Production

Triticale, a hybrid of wheat and rye, is one of the most promising grain crops. In terms of productivity, the level of metabolizable energy, and the composition of essential amino acids, triticale surpasses rye and is not inferior to wheat. It is resistant to the most dangerous diseases and pests. In terms of nutritional value, triticale can compete with wheat, corn, sorghum, and barley. The presence, however, of antinutrients in triticale such as non-starch polysaccharides, alkylresorcinols, and trypsin inhibitors significantly reduces the biological value of this crop. In the global practice of compound feed production, there are many methods and technologies for processing grain raw materials to increase their nutritional value. Enzymatic treatment and extrusion technologies are worthy of special attention. The high content of triticale in the compound feed of poultry breeder flocks should be used effectively, taking into account the characteristics of triticale varieties and climatic conditions. An optimal triticale level in feed (15% for layer and broiler chicks) may improve body weight gain and reduce feed costs when raising replacement young stock. Layer breeder flocks fed a 20% triticale-based diet may have increased egg production, high viability, and flock uniformity. Producing triticale–soy and triticale–sunflower extrudates and supplementing the diet of poultry flocks with essential amino acids represent promising avenues for maximizing the benefits of triticale. Innovative methods of achieving this goal should be further developed and put into practice, particularly given the expansion of triticale’s cultivation areas.

Lameness caused by Staphylococcus aureus in poultry: A review

Staphylococcus aureus is a gram-positive, facultative anaerobe coccus, which is a member of the commensal microbiota of skin and mucous membranes in humans and animals and sometimes can cause infection or disease. This bacterium produces variable toxins and enzymes including at least five types of exotoxins that leads to cell membrane damage. Staphylococcus aureus can cause a wide range of clinical and pathologic lesions including acute or subacute septicemia, embryo mortalities, omphalitis and yolk sac infection, arthritis and synovitis, osteomyelitis, vesicular dermatitis, gangrenous dermatitis, pododermatitis and other disorders in different avian species. Staphylococcus aureus infections are among the most important diseases of poultry industry, particularly, in broiler breeder flocks. Staphylococcal infections can cause large economic losses due to lameness, arthritis, poor weight gain, decreased egg production, and loss of flock uniformity. This paper reviews the characteristics of Staphylococcus aureus and its role in lameness and arthritis in poultry.

Effects of Turmeric (Curcuma longa) Powder Additive on Growth Performance, Flock Uniformity and Blood Profile of Japanese Quails (Coturnix japonica)

Turmeric has been reported to possess various bioactive compounds. This study examined the effects of turmeric powder as a natural feed additive on the growth performance, flock uniformity, and blood profile of Japanese quail. Two hundred and fifty-six (256) male Japanese quail of average weight of 115.00 ± 5g were used for this study. The birds were randomly allotted to four dietary groups with four replicates of sixteen birds each in a Completely Randomized Design. Turmeric powder was added in the diet at 0.00%, 0.25%, 0.50%, and 0.75% to form diet D1, D2, D3, and D4. All the data collected for growth performance were significantly influenced (P&lt;0.05). Birds fed D2 had the highest average daily weight gain (1.33 g/bird) followed by those fed D3 (1.25 g/bird), D1 (1.17 g/bird), and D4 (1.09 g/bird). Birds fed D2 had the highest total feed intake (829.59 g/bird) and D1 had the lowest (786.34 g/bird). Birds fed D4 had the highest flock uniformity and feed conversion ratio (59.40% and 18.17 respectively). All the haematological parameters were significant (P&lt;0.05) except pack cell volume, haematocrit, haemoglobin, red blood cell, and platelet. Birds fed D2 had the highest mean corpuscular volume (163.00 fL). Birds fed D3 had the highest white blood cell count (189.50 103/μL), heterophils (55.00 cells/μL), and eosinophils (1.50 cells/μL). Lymphocyte and platelet count were highest in the birds fed D4. All the serum biochemical parameters were significant (P&lt;0.05) except asparate aminotransferase, cholesterol, and low-density lipoprotein. Except for total protein, alanine aminotransferase, and globulin, all the significant parameters were highest in birds fed D1. 0.25% of turmeric powder can be included in quail’s diet without adverse effect on the growth performance and health.

Effects of grain-based pecking blocks on productivity and welfare indicators in commercial broiler chickens.

This experiment was conducted to investigate the effect of grain-based pecking blocks on productivity and welfare status at two commercial broiler welfare-certified farms. Production and welfare indicators were assessed at two farms (designated Farm A and B). Both farms had two windowless houses with forced tunnel-type ventilation and housed broilers at stocking densities of approximately 16.7 birds/m2 (Farm A) and 16.8 birds/m2 (Farm B). Each house was divided into two or three equal sections and was provided with or without pecking blocks. Grain-based pecking blocks, measuring 25 × 25 × 25 cm, were given to broilers in both farms at 1 block per 1,000 birds. Various parameters including productivity (body weight and flock uniformity), corticosterone levels (in fecal droppings and feathers), footpad dermatitis, hock burn, feather dirtiness, gait score, litter quality, body surface temperature, and volatile fatty acids in fecal samples were assessed at 26 days of age, whereas litter quality was analyzed at 13 and 26 days of age. There were no significant effects of providing pecking blocks on productivity (body weight and uniformity), fecal and feather corticosterone, welfare indicators (i.e., footpad dermatitis, hock burn, feather cleanliness, and gait score), and litter quality (i.e., moisture, nitrogen, and pH). No differences in body surface temperature between the control and enrichment treatments were noted in Farm B, but body surface temperatures of the head (p = 0.029) and legs (p = 0.011) in the enrichment vs. control group were elevated in Farm A. Butyrate concentration in the enrichment vs control group was higher in Farm B (p = 0.023), but this effect was not detected in Farm A. It is concluded that grain-based pecking blocks did not affect performance and welfare indicators. Further studies are warranted to elucidate the potential impact of grain-based pecking blocks on gut health indicators.

279 Impact of Increasing Additions of Choline Chloride on Broiler Chicken Body Weight Variability

Abstract Previously, we observed a linear improvement in feed conversion and no difference in body weight (BW) in broiler chickens fed increasing additions of choline chloride in a diet with reduced digestible methionine (dMet) reared under summer environmental conditions. Poor uniformity in broiler carcass weights can negatively impact processing yields and profitability. The objective was to evaluate the impacts of increasing choline concentration on BW variation of broilers from the previous study. Yield Plus × Ross 708 male broilers (n = 2,232) were reared for 41 d on used litter in floor pens (n = 31 birds per 2.3 m2 pen). Birds were fed 1 of 6 corn and soybean meal-based, reduced dMet diets containing 0, 400, 800, 1,200, 1,600, or 2,000 mg added choline chloride per kg of feed (n = 12 pens per treatment). Diets were provided in 3 phases: starter from d 0 to 15 with 0.42% dMet, grower from d 16 to 28 with 0.42% dMet, and finisher from d 29 to 41 with 0.37% dMet. Rearing temperatures began at 34.4 °C, were reduced over 21 d to 26.7 °C and maintained there until d 41. Individual weights were collected at 15, 28, and 41 d. Broilers (n = 10 per pen based on proximity to pen median BW) were processed on d 43. The distance of each bird from both mean and median of the pen, added choline treatment, and whole flock BW over time was calculated. Uniformity was reported comparing within a pen to the pen, treatment, and flock averages. Intra-pen CV was calculated using pen mean and median weights. Data were analyzed as a 1-way ANOVA using SAS PROC GLIMMIX with added choline as main effect. Means were separated at P ≤ 0.05 with tendencies declared at 0.05 &amp;lt; P ≤ 0.10 using the PDIFF option, and orthogonal contrasts were evaluated. Supplementing the diet with choline increased individual bird distance from the treatment and flock average BW from d 15 to 41 (P ≤ 0.0244). Intra-treatment and flock uniformity showed a quadratic response to increasing additions of choline at d 41 (P ≤ 0.0214) as did the CV within pens at d 41 (P = 0.0455). Variability of carcass part weights of birds selected for processing was not impacted by choline addition. While supplementing dMet-deficient diets with choline chloride can improve broiler feed efficiency without impacting BW, it may alter variation among individual birds depending on the concentration in the diet. These results indicate that there is variation in how individual birds respond to choline chloride additions and highlight the importance of analyzing variation as part of comprehensive feed additive evaluation to deepen the understanding of its impacts.

Health effects of feed dilution and roughage in Ross 308 broiler breeder cockerels

To ensure reproductivity and prevent obesity, broiler breeder's growth rate is controlled by quantitative feed restriction. However, feed restriction is associated with chronic hunger, frustration, and abnormal behaviors, thus representing a welfare problem. Feed diluted with insoluble fiber is an alternative, allowing larger amounts of feed and more gut filling, increasing satiety without increasing the caloric intake. Previous research on feed dilution has focused on pullets not cockerels. In addition, the health effects of diluted feed are less explored. The aim of this study was to investigate the effects of feed dilution and roughage on health indicators in broiler breeder cockerels, 5 to 10 wk of age (WOA), a very feed restricted period. In total, 200 Ross 308 broiler breeder cockerels were housed in 12 pens (6 pens/treatment), 16 to 17 birds per pen. The treatments were standard feed (Control) and feed diluted with (20%) insoluble oat hulls and 150 g of roughage (lucerne/alfalfa) daily per pen (D+R). The D+R birds received 20% more feed per day. Body weight, pecking injuries, footpad dermatitis (FPD), and litter quality were recorded weekly between 5 and 9 WOA. At 10 WOA all birds were euthanized and subjected to postmortem assessment. D+R birds tended to weigh more than controls (P=0.055), but diet did not affect flock uniformity (P=0.57). The weekly assessment showed no effect of treatment on foot pad lesion scores (P=0.31). However, an effect on FPD was observed postmortem (P=0.04), where Control had slightly better footpad condition compared to the D+R group. Litter had to be completely changed in 2 control pens during the trial, due to quality deterioration. There was no effect of treatment on the weight of specific organs, the length of the gut, the intestinal mucosa, nor on the incidence of wounds on the head (P=0.15). Overall, these results indicate that feed dilution and roughage have neither adverse nor beneficial health effects on Ross 308 broiler breeder cockerels.

Influence of sex and rearing method on performance and flock uniformity in broilers-implications for research settings.

Male and female broiler chickens differ in their growth performance, carcass part weights and nutrient requirements. The potential reasons for these differences have been explored by looking at differences in nutrient digestibility, nutrient transporter gene expression as well as gut microbiota populations between male and female birds. Studies have shown that male broilers have higher crude protein requirements compared to female broilers. The expression of monosaccharide and amino acid transporters show conflicting results as expression depends on the interactions between sex and bird age and breed as well as which tissue is sampled. Differences in microbiota populations between the genders were reported which may contribute towards performance differences, however research in this area is limited. The differences observed between the sexes contribute to increased variation in nutrition trials, and the potential to rear birds as equally mixed-sex becomes an option to reduce the variation introduced by the sex effect. Difference in rearing options obviously would only be feasible provided a quick, practical and cost-effective method of sexing birds is available, a topic that is also discussed in this review.

Rearing broilers as mixed or single-sex: relevance to performance, coefficient of variation, and flock uniformity

With known variation in performance between male and female broilers and the fact that sourcing single-sex birds for use in research is becoming increasingly difficult, it becomes important to determine the effect of rearing method with male and female broilers on between-pen variation and body weight (BW) uniformity. We evaluated the performance response of broilers reared as single or mixed-sex to standard and reduced crude protein (CP) diets. The study was designed as a 2 × 3 factorial arrangement of treatments consisting of 672 Cobb-500 broilers assigned to 48 floor pens with 6 treatments, 8 replicates, and 14 birds per pen. The factors were rearing method (male single-sex, female single-sex, or equally mixed-sex) and dietary CP level (standard or reduced). For the overall period of the trial (d 0–35) there was a significant effect (P < 0.001) of rearing method and CP level on feed intake (FI) and feed conversion ratio (FCR). There was also a significant interaction between rearing method and CP level for BWG during d 0 to 35 (P < 0.01). There was a significant interaction between CP level and sex on d 34 BW (P < 0.01) where the reduced CP diet decreased the BW of both males and females, but to a greater extent the BW of the female birds. Dietary CP level had a significant effect on relative breast and drumstick weights with birds fed the reduced CP diet having significantly lower breast weights (P < 0.001) and higher drumstick weights (P < 0.01).This study suggests that male and female broilers have different CP requirements, and rearing birds as equally mixed-sex results in the lowest CV% for performance parameters and best BW uniformity compared to single-sex birds. Furthermore, when low CP diets are fed to broilers, they will prioritize the growth of more important body parts such as the legs.

Einfluss der Junghennenqualität auf das Auftreten von Gefiederschäden, Hautverletzungen und die Mortalität in der Legeperiode kommerzieller Legehennenhaltungen

Abstract Laying hen farmers increasingly optimize relevant causal complexes to reduce severe feather pecking. Previous studies demonstrated the relevance of the rearing period on plumage condition during the laying period. Therefore, we examined the effects of pullet quality at the time of housing in the laying stable on plumage condition, skin condition, performance, and animal losses in the laying period under field conditions in a total of 28 laying flocks (9 white-egg layer flock and 19 brown-egg layer flocks) in floor (n = 21) or free-range housing systems (n = 7) with an average flock size of 12,357 hens (median). Pullet quality (PQ) was determined at post-housing examination based on plumage condition, flock uniformity, and target body mass. This resulted in a classification in flocks with high (n = 7), moderate (n = 14), and low PQ (n = 7). Over the subsequent laying period, plumage and skin scoring at seven time points and a continuous documentation of performance data and animal losses were performed.

Impact of every-day versus skip-a-day feeding of broiler breeder pullets during rearing on body weight uniformity and reproductive performance

Genetic selection for increased growth rate in broilers makes feed restriction programs such as skip-a-day (SAD) feeding, for broiler breeders essential to managing body weight, flock uniformity, and reproductive performance. The objective of this experiment was to compare intestinal development, weight gain of breeder pullets, and reproductive performance (22–45 wk) when fed a high fiber diet (3.8% crude fiber) on either an every-day (ED) or SAD basis during rearing. The same developer ration and feed amounts were fed to both treatments. Day-old Ross 708 pullet chicks (n = 912) were randomly distributed into 4 floor pens (n = 228/pen, 2 pens/treatment). At 20 wk of age all birds were weighed, and the coefficient of variation (CV) and average body weight was calculated for each treatment. Birds were then distributed into 10 lay pens (n = 35 birds/pen, 5 pens/treatment) at 21.5 wk of age. Light was increased from 8 h to 15.25 h at move to the lay facility, and all birds were daily fed for the remainder of the study. Data were analyzed by SAS SLICE using a significance level of P ≤ 0.05. During lay, 25% of the birds from each treatment were weighed weekly to adjust feed and monitor body weight. At 21 wk the ED fed pullets were more uniform (P = 0.0007) than the SAD fed pullets. Eggs were collected daily and set for hatch every 4 wk from 28 to 42 wk of age. No significant difference in the hatch data were observed. The ED fed birds achieved first egg at 166 d of age while the SAD fed birds achieved first egg at 173 d of age. Specific gravity was measured every 2 wk from 30 to 40 wk, with ED reared birds having better overall eggshell quality (P = 0.02) and greater egg weight (P < 0.0001) than those fed SAD. Feeding a high fiber diet on an ED basis during rearing, improved body weight uniformity in rearing, encouraged early lay, improved eggshell quality and increased egg weight.

Does light color during brooding and rearing impact broiler productivity?

Light color during brooding and rearing may impact broiler production; however, literature results are inconsistent. To address this, the effects of 3 wavelength spectra on broiler performance in 2 sex and 2 genotypes (Ross YPMx708 and EPMx708) were studied. Broilers were raised (d 0–35) under wavelength programs provided by LED light bulbs (blue (455 nm), green (510 nm) or white) under similar intensities (clux). Two trials were conducted (total number of birds = 14,256; 6 room replications per lighting treatment; 18 replicate pens per light × sex × genotype). Data were analyzed as a 3 × 2 × 2 (wavelength × sex × genotype) factorial design, with trial as a random variable block and wavelength nested within rooms (Proc Mixed, SAS 9.4). Birds raised under white light were heavier than under blue or green light at d7 (P = 0.004), and green at d14 (P = 0.03). Feed intake, gain-to-feed efficiency and flock uniformity (d15, 28) did not differ. Mortality only differed at wk 5, when broilers raised under white light had higher mortality than those raised under blue (P = 0.03). YPM-708 were heavier at 21 d (P = 0.007), 28 d (P = 0.001), and 35 d (P < 0.0001), had a better total feed conversion rate (P < 0.0001), higher mortality for wk 1 (P = 0.001), lower mortality during the last wk (P = 0.02) and better uniformity at 28 d (P = 0.01) than EPM-708 broilers. Males were heavier at all measured ages except d0 (d7-P = 0.03, other weeks P < 0.0001), had better total feed conversion (P < 0.0001), increased weekly mortality except for wk 1 (wk2-P = 0.04, wk3-P = 0.002, wk4, 5, and total-P = 0.0001) and were less uniform (P = 0.0002) than females. YPM-708 and EPM-708 males had higher total feed intake (P < 0.0001), and males raised under white light had higher mortality than females raised under white or blue light (P = 0.01). To conclude, the use of specific light colors (blue and green) had only minor impacts on broiler production when light intensity was equalized and balanced for bird spectral sensitivity, and its use to improve productivity does not appear to be advantageous for broilers in a commercial setting.

Stocking density effects on turkey hen performance to 11 weeks of age

Stocking density (SD) affects economic return for turkey production and can impact performance parameters. In this study (2 experimental blocks), Nicholas Select hens (n = 3,550 poults/block) were randomly placed in 1 of 4 SD treatments of 30, 40, 50, or 60 kg/m2 in open rooms (67.5 m2) with 4 replications per treatment. Feeder and drinker space were equalized on a per bird basis. Air quality was measured, and ventilation was adjusted to equalize ammonia and carbon dioxide levels across all rooms. Group BW and feed consumption were measured on d 0 and wk 3, 5, 8, and 11. BW gain and mortality corrected feed-to-gain ratio were calculated. Mortality and culls were recorded daily and necropsied for cause of death. At wk 8 and 11, flock uniformity was evaluated (30 birds/replicate). Data were analyzed using regression analyses in SAS 9.4 (Proc Reg for linear regression and Proc RSReg for quadratic regression; SD as independent variable). An ANOVA was performed for air quality (Proc Mixed; SAS 9.4) and a Tukey's range test was used to separate means. Differences were considered significant when P ≤ 0.05. Carbon dioxide and ammonia were consistent across treatments for both blocks. At wk 11, BW decreased linearly as SD increased (P = 0.05). There was a tendency for overall BW gain to decrease linearly as SD increased (P = 0.06). Feed consumption decreased as SD increased during wk 8 to 11 (linear; P < 0.01) and from wk 0 to 11 (quadratic; P = 0.04). SD had no impact on feed efficiency, mortality, or uniformity. Total aggression related mortality and culls were highest in the 30 kg/m2 treatment (linear; P = 0.02). A brief economic analysis was performed utilizing commercial poult and feed costs and income at marketing. Net room income increased as SD increased (linear; P < 0.01). The results indicate that high SD negatively impacted turkey hen final BW and feed consumption, but no effect was observed on feed-to-gain ratio, percent mortality, or uniformity.

Effects of Key Farm Management Practices on Pullets Welfare-A Review.

Simple SummaryStudies on animal behavior and welfare have reported that improving the management practices of pullets can enhance their growth, as well as their physical and mental condition, thus benefiting the productivity of laying hens. Therefore, in this review, we elaborated on the key effective farm management measures, including housing type and matching, flock status, and environmental management and enrichment, to provide the necessary information to incorporate welfare into chicken rearing and its importance in production, with the aim of improving the quantity and quality of chicken products.Studies on animal behavior and welfare have reported that improving the management practices of pullets can enhance their growth, as well as their physical and mental condition, thus benefiting the productivity of laying hens. There is growing confidence in the international community to abandon the conventional practices of “cage-rearing and beak-trimming” to improve the welfare of chickens. Therefore, in this review, we summarized some of the effective poultry management practices that have provided welfare benefits for pullets. The results are as follows: 1. Maintaining similar housing conditions at different periods alleviates fear and discomfort among pullets; 2. Pullets reared under cage-free systems have better physical conditions and temperaments than those reared in cage systems, and they are more suitable to be transferred to similar housing to lay eggs; 3. Improving flock uniformity in appearance and body size has reduced the risk of pecking and injury; 4. Maintaining an appropriate population (40–500 birds) has reduced flock aggressiveness; 5. A combination of 8–10 h of darkness and 5–30 lux of light-intensity exposure via natural or warm white LED light has achieved a welfare–performance balance in pullets. (This varies by age, strain, and activities.); 6. Dark brooders (mimicking mother hens) have alleviated fear and pecking behaviors in pullets; 7. The air quality of the chicken house has been effectively improved by optimizing feed formulation and ventilation, and by reducing fecal accumulation and fermentation; 8. Complex environments (with litter, perches, straw bales, slopes, platforms, outdoor access, etc.) have stimulated the activities of chickens and have produced good welfare effects. In conclusion, the application of comprehensive management strategies has improved the physical and mental health of pullets, which has, in turn, improved the quantity and quality of poultry products.

Sunflower Meal Inclusion Rate and the Effect of Exogenous Enzymes on Growth Performance of Broiler Chickens.

Simple SummaryOver the years, there has been an increase in the price of traditionally used protein sources such as soybean meal (SBM) in broiler feed. This has necessitated the need for alternative protein sources that can partially substitute the SBM protein and reduce the cost of feeding. Sunflower meal (SFM), a by-product from the oil processing industry, is available in significantly high quantities throughout the year at lower cost. SFM can be produced in drought-stricken places with good harvest and is less prone to fungal infestation. Although SFM has protein levels ranging between 32 and 37 percent, its inclusion levels in broiler diets have been limited to 5% due to high concentration of non-starch polysaccharides, low metabolizable energy and lysine levels. This presents challenges in feed manufacturing, since composition depends on the amount of oil extracted and retained hulls, with effects on the digestive efficiency of broiler chicks, especially in the first 21 d of growth. The use of multi-enzymes that target specific substrates in SFM can potentially allow an increase in its inclusion levels, thereby reducing the deleterious anti-nutritional effects from non-starch polysaccharides (NSPs). Additionally, multienzyme supplementation can result in flock uniformity and environmental pollution reduction due to less nutrient loss in manure.The study examined the effect of de-hulled sunflower meal (SFM) inclusion rate and exogenous enzymes (EE) on broilers production performance. A four-feeding phase of pre-starter (1–9 d), grower (10–20 d), finisher (21–28 d) and post-finisher (29–35 d) was used with SFM included as low (BSL) and high (BSH) in all phases. BLS inclusion was 3% throughout phases and BSH inclusion was 7.5%, 10%, 13% and 13.5% for the 4-phases. Each SFM had a negative control (NC) (BSL− and BSH−) and positive (PC) (BSL+ and BSH+) control with additional 80 kcal Apparent Metabolizable Energy. Enzymes: xylanase (X), xylanase + beta-glucanase (XB), xylanase + beta-glucanase + protease (XBP) and xylanase + amylase + protease (XAP) were added to the NC and PC to give 6 treatments. Pen body weight gain (BWG) and feed intake (FI) were determined at 9, 20, 28 and 35 d and feed conversion ratio (FCR) was calculated accordingly. Diets were fed ad libitum to 1920 male Ross 308 broilers. Diet type, enzyme and diet by enzyme interactions were not significantly different amongst treatment diets. During the pre-starter and the grower phase, all studied parameters did not significantly differ from each other. All studied parameters were significantly influenced by enzyme addition and diet-type and enzyme interaction at 35 d except for diet type on FCR. Broilers fed BSH supplemented with XAP recorded the highest BWG (2.69 kg), whereas broiler chickens on BSL and supplemented with XBP recorded the lowest BWG (2.60 kg). SFM can be increased to 13% and 13.5% finisher and post-finisher diets without negatively affecting performance, and X and XAP enzymes can improve BWG of broilers grown to 35 d.

Flock Uniformity – A New Poultry Welfare Indicator?

Directive 2007/43/CE establishes the system for assessing the welfare of poultry at the slaughterhouse level, which consists of a systematic assessment of indicators by the slaughterhouse's official veterinarian (OV). In Portugal those indicators include mortality rate on the farm and during transport to the slaughterhouse, as well as post mortem findings such as footpad dermatitis (FPD). Nevertheless, the increasing importance of this topic leads to a dynamic search for novel welfare indicators such as flock uniformity. Reduced animal welfare can be indicated by poor flock uniformity due to either general housing or management problems, or bird health problems. For that reason, the aim of this study was to investigate the usefulness of the parameter “flock uniformity “(FU) as an indicator of animal welfare to be used during slaughter of commercial broiler flocks. For that, a total of 26 randomly selected mixed-sex Ross 308 broiler flocks were studied. All batches were raised under similar farm management systems with a medium age of slaughter of 35 days. To study the uniformity, 10% of each batch was observed and categorized after stunning at the slaughterhouse, using the following scores based on % of small animals observed: score 1 ([0 -2,5%[; high uniformity); score 2 ([2,5-5%[; normal uniformity); score 3 ([5-7,5%[; bad uniformity); score 4 (≥7,5%; no uniformity). Additionally, the following percentage data were collected for each flock: mortality in transport, total condemnation (TC), the % of TC only due to disease cause and the % of TC due to errors related to slaughter process. The results showed that poorer uniformity was highly associated with increased rejection level (p= 0.002) and increased rejections caused by disease (p = 0.001). This highlights the potential use of this parameter as an animal welfare indicator and also as a criterion to be used under a risk-based meat inspection approach: The worse the FU, the more time the OV must dedicate to the post-mortem inspection of that batch

Flock Uniformity – A New Poultry Welfare Indicator?

Directive 2007/43/CE establishes the system for assessing the welfare of poultry at the slaughterhouse level, which consists of a systematic assessment of indicators by the slaughterhouse's official veterinarian (OV). In Portugal those indicators include mortality rate on the farm and during transport to the slaughterhouse, as well as post mortem findings such as footpad dermatitis (FPD). Nevertheless, the increasing importance of this topic leads to a dynamic search for novel welfare indicators such as flock uniformity. Reduced animal welfare can be indicated by poor flock uniformity due to either general housing or management problems, or bird health problems. For that reason, the aim of this study was to investigate the usefulness of the parameter “flock uniformity “(FU) as an indicator of animal welfare to be used during slaughter of commercial broiler flocks. For that, a total of 26 randomly selected mixed-sex Ross 308 broiler flocks were studied. All batches were raised under similar farm management systems with a medium age of slaughter of 35 days. To study the uniformity, 10% of each batch was observed and categorized after stunning at the slaughterhouse, using the following scores based on % of small animals observed: score 1 ([0 -2,5%[; high uniformity); score 2 ([2,5-5%[; normal uniformity); score 3 ([5-7,5%[; bad uniformity); score 4 (≥7,5%; no uniformity). Additionally, the following percentage data were collected for each flock: mortality in transport, total condemnation (TC), the % of TC only due to disease cause and the % of TC due to errors related to slaughter process. The results showed that poorer uniformity was highly associated with increased rejection level (p= 0.002) and increased rejections caused by disease (p = 0.001). This highlights the potential use of this parameter as an animal welfare indicator and also as a criterion to be used under a risk-based meat inspection approach: The worse the FU, the more time the OV must dedicate to the post-mortem inspection of that batch.

The link between broiler flock heterogeneity and cecal microbiome composition

BackgroundDespite low genetic variation of broilers and deployment of considerate management practices, there still exists considerable body weight (BW) heterogeneity within broiler flocks which adversely affects the commercial value. The purpose of this study was to investigate the role of the cecal microbiome in weight differences between animals. Understanding how the gut microbiome may contribute to flock heterogeneity helps to pave the road for identifying methods to improve flock uniformity and performance.ResultsTwo hundred eighteen male broiler chicks were housed in the same pen, reared for 37 days, and at study end the 25 birds with highest BW (Big) and the 25 birds with lowest BW (Small) were selected for microbiome analysis. Cecal contents were analyzed by a hybrid metagenomic sequencing approach combining long and short read sequencing. We found that Big birds displayed higher microbial alpha diversity, higher microbiome uniformity (i.e. lower beta diversity within the group of Big birds), higher levels of SCFA-producing and health-associated bacterial taxa such as Lachnospiraceae, Faecalibacterium, Butyricicoccus and Christensenellales, and lower levels of Akkermansia muciniphila and Escherichia coli as compared to Small birds.ConclusionCecal microbiome characteristics could be linked to the size of broiler chickens. Differences in alpha diversity, beta diversity and taxa abundances all seem to be directly associated with growth differences observed in an otherwise similar broiler flock.

Corn kernel hardness, drying temperature and amylase supplementation affect live performance and nutrient utilization of broilers

Drying temperature (DT) of corn can influence its nutritional quality, but whether this is influenced by endosperm hardness is not clear. Two parallel experiments were conducted to investigate the effects of 2 yellow dent corn hybrids with average and hard kernel hardness, dried at 3 temperatures (35, 80, and 120°C), and 2 supplementation levels of an exogenous amylase (0, 133 g/ton of feed) on live performance, starch and protein digestibility, and energy utilization of Ross 708 male broilers. Twelve dietary treatments consisting of a 2 × 3 × 2 factorial arrangement were evaluated using 3-way ANOVA in a randomized complete block design. In Experiment 1, a total of 1,920 male-chicks were randomly allocated to 96 floor pens, whereas 480 day-old chicks were distributed among 96 cages for Experiment 2. At 40 d, interaction effects (P < 0.05) were detected on BWG, FCR, and flock uniformity. Supplementation with exogenous amylase resulted in heavier broilers, better FCR and flock uniformity, only in the diets based on corn dried at 35°C. Additionally, interaction effects were observed on FCR due to kernel hardness and DT (P < 0.01), kernel hardness and amylase supplementation (P < 0.001), and DT and amylase supplementation (P < 0.05). Exogenous amylase addition to the diets based on corn with an average hardness improved FCR up to 2 points (1.49 vs. 1.51 g:g) whereas there was no effect of amylase on FCR of broilers fed diets based on corn with hard endosperm. Total tract retention of starch was increased (P < 0.05) in broilers fed diets based on corn with average kernel hardness compared to hard kernel. Corn dried at 80 and 120°C had up to 1.21% points less starch total tract retention than the one dried at 35°C. Supplementing alpha-amylase resulted in beneficial effects for broiler live performance, energy utilization, and starch total tract digestibility results. Treatment effects on starch characteristics were explored. Corn endosperm hardness, DT and exogenous amylase can influence the live performance of broilers. However, these factors are not independent and so must be manipulated strategically to improve broiler performance.