Proposed changes in living conditions for broilers under the National Organic Program will have limited economic effects

In the current paper, we estimate the costs and benefits of implementing the proposed rule for changes in living conditions for organic broilers. In contrast to the effects of the proposed rule for changes in living conditions for laying hens, the effects of the rule on organic broilers is anticipated to be relatively limited. All producers are already in compliance with option 2 of the rule, and changes required under option 3 are minimal for most producers. Using the per-farm estimated regulatory costs and the estimates of production volumes and actual prices, the total estimated annual industry cost under option 3 is $2.4 million, which represents 0.1% of total industry revenue. The estimated benefits associated with this type of perceived animal welfare improvement are high enough to cover the anticipated cost, and the proposed option easily passes the benefit-to-cost ratio test.     

Prevalence of gastrointestinal helminth infections in free-range laying hens under mountain farming production conditions

1. A cross-sectional study was conducted from September 2015 to July 2016 in South Tyrol, Northern Italy to examine the prevalence of gastrointestinal helminths in free-range laying hens under mountain farming production conditions.

2. A total of 280 laying hens from 14 free-range mountain farms (4 organic, 10 conventional) were randomly collected at the end of the laying period. Faecal samples were taken to analyse faecal egg counts (FEC) and faecal oocyst counts (FOC). The gastrointestinal tracts were removed post mortem and examined for the presence of helminths.

3. In faeces, FEC values averaged 258 eggs per g of faeces, which were dominated by Ascaridia galli and Heterakis gallinarum. Mean FOC was 80 oocysts/g. In the gastrointestinal tract, at least one nematode species was found in 99.3% of the examined hens. H. gallinarum was the most prevalent nematode (95.7%), followed by Capillaria spp. (66.8%) and A. galli (63.6%). Thirty per cent of the chickens were infected with cestodes (tapeworms). Correlation coefficients between worm counts of H. gallinarum, Capillaria spp. and A. galli ranged from 0.41 to 0.51.

5. The helminth prevalence did not differ between conventional and organic farms, whereas total worm burden was higher in organic compared with conventional farms (318.9 vs. 112.0). Prevalence and infection intensity did not differ between farms that used anthelmintic treatments and those that did not.

6. In conclusion, free-range laying hens under the studied mountain farming conditions are at high risk of nematode infection, especially in organic systems. The vast majority of hens are subclinical infected with at least one helminth species.     

Organic trace minerals on productive performance,egg quality and immune response in Bovans White laying hens

This study was performed in 360 laying Bovans White hens and aimed to evaluate the effect of Carbo‐Amino‐Phosphate‐Chelates (CAFQ) as a mineral premix and its 30% reduction by compared to inorganic trace minerals (ITM) concerning its performance, egg quality, tibia breaking strength and immunity. Sixty‐week‐old hens were assigned into three treatments with 10 replicates of 12 birds each. Treatments were as follows: (a) (100% ITM), (b) (100% CAFQ) and (c) (70% CAFQ). Based on the results obtained during 12 weeks, under the current test conditions, improved yolk colour (p < 0.05); shell breaking strength (p < 0.05); and storage time (p < 0.05) were observed in hens fed with a diet reduced by 70% in CAFQ inclusion showed similar performance behaviour and better egg breaking strength regarding with ITM, suggesting the possibility of minimizing the inclusion of trace minerals in laying hen diets improving environmental impact, in contrast to the use of inorganic sources of minerals.     

Plasma dispositions and concentrations of ivermectin in eggs following treatment of laying hens

AIMS: To determine the plasma disposition and concentrations of ivermectin (IVM) in eggs produced by laying hens following S/C, oral and I/V administration.

METHODS: Twenty-four laying hens, aged 37 weeks and weighing 1.73 (SD 0.12) kg were allocated to three groups of eight birds. The injectable formulation of IVM was administered either orally, S/C, or I/V, at a dose of 0.2?mg/kg liveweight, following dilution (1:5, v/v) with propylene glycol. Heparinised blood samples were collected at various times between 0.25 hours and 20 days after drug administration. Eggs produced by hens were also collected daily throughout the study period. Samples of plasma and homogenised egg were analysed using HPLC.

RESULTS: Maximum concentrations of IVM in plasma and mean residence time of IVM were lower after oral (10.2 (SD 7.2) ng/mL and 0.38 (SD 0.14) days, respectively) than after S/C (82.9 (SD 12.4) ng/mL and 1.05 (SD 0.24) days, respectively) administration (p<0.01). The time to maximum concentration and elimination half-life were shorter following oral (0.14 (SD 0.04) and 0.23 (SD 0.11) days, respectively) than S/C (0.25 (SD 0.00) and 1.45 (SD 0.45) days, respectively) administration (p<0.01). IVM was first detected in eggs 2 days after treatment in all groups and was detected until 8 days after oral and I/V administration, and until 15 days after S/C administration. Peak concentrations of IVM were 15.7, 23.3 and 1.9?µg/kg, observed 2, 5 and 4 days after I/V, S/C and oral administration, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE: The low plasma bioavailability of IVM observed after oral administration in laying hens could result in lower efficacy or subtherapeutic plasma concentrations, which may promote the development of parasitic drug resistance. Due to high IVM residues in eggs compared to the maximum residue limits for other food-producing animal species, a withdrawal period should be necessary for eggs after IVM treatment in laying hens.     

有机酸和益生元对蛋鸡生产性能和蛋壳质量的影响

文章旨在评估不同钙磷水平日粮中添加有机酸和益生元对蛋鸡产蛋量和蛋壳品质的影响。试验选择504只罗曼褐壳蛋鸡,根据产蛋率一致的原则随机分为14个组,每组36只鸡,采用蛋鸡单笼饲养。试验日粮采用2×7因子设计,即两个钙和磷水平(正常组和低水平组)以及不添加、添加0.8%的菊粉和低聚糖、0.5%挥发性脂肪酸中链脂肪酸、0.25%挥发性脂肪酸+0.25%中链脂肪酸、0.4%菊粉+0.25%中链脂肪酸,试验从26w开始到70w结束。试验结果发现,各处理组对产蛋率、采食量、饲料转化率均无显著影响(P>0.05)。低钙磷日粮显著降低了蛋壳百分率、蛋壳厚度、蛋壳密度和蛋壳强度(P<0.05)。日粮添加益生元和有机酸能显著改善46、58和70w蛋壳质量,其中菊粉和中链脂肪酸对蛋壳质量的改善最为显著(P<0.05)。日粮钙、磷水平与益生元和有机酸对各指标的影响无显著交互作用(P>0.05)。结果表明,日粮添加有机酸可以降低饲料pH,同时益生元可以调控肠道功能,从而对高龄高产蛋鸡蛋壳品质有改善作用。     

Lead concentrations in the blood and eggs of backyard laying hens

AIMS: To investigate the prevalence of lead exposure in hens and eggs from backyard poultry in a sample of Auckland households, the relationship between concentrations of lead in the blood of the hens and in the shells and yolks of eggs from the same household, and to examine associations with measures of hen health, environment and husbandry factors.

METHODS: Thirty households participated in the study from August to November 2016, each providing one adult hen for sampling, an egg from the household if available, and completing a questionnaire on hen husbandry. Concentrations of lead in blood were determined using a portable lead analyser. Eggs were analysed for concentrations of lead in the yolk and shell using inductively coupled plasma mass spectrometry after biological digestion with a mixture of nitric and hydrochloric acid.

RESULTS: Twenty three of 30 hens (77%) showed evidence of lead exposure, with median concentrations of lead in blood of 0.77 (min?<0.16, max 8.02) μmol/L. All eggs showed evidence of lead exposure, with concentrations of lead in the yolk ranging from 0.003–1.07?mg/kg, and concentrations of lead in the eggshell ranging from <0.1–0.82?mg/kg. A positive correlation existed between concentrations of lead in the blood of a hen and concentrations of lead in egg yolk from the same hen (R²=0.97), and both the yolk (R²=0.58) and shell (R²=0.30) of an egg from her flock. No association was found between concentrations of lead in blood and hen health indices measured in this study. Concentrations of lead in blood were higher in hens from properties with homes built before 1941 than between 1941–1960 (p=0.03), and in hens from properties with weatherboard homes than brick homes (p=0.049).

CONCLUSIONS AND CLINICAL RELEVANCE: There was a high prevalence of lead exposure in this sample of Auckland backyard chickens, with the majority of hens being sub-clinically affected. Associations were found between concentrations of lead in the blood of the hens, and properties with homes built before 1941 and clad in weatherboard. Concentrations of lead in over half the egg yolks sampled were at levels sufficient to warrant human health concern. The assessment of concentrations of lead in backyard poultry and eggs intended for human consumption is recommended to protect human and bird health.     

The effects of formic acid-treated shrimp meal on laying performance and egg quality in aged laying hens

An experiment was carried out to measure the suitability of using formic acid-treated shrimp meal (TSM) as a protein source for aged laying hens. Shrimp meal (SM), air-dried shrimp waste was treated with 3% formic acid (w/v) at room temperature for 20 min, sun-dried, ground to pass through 1.0 mm mesh screen and then ready to use as the TSM. A total of 56 Single Comb White Leghorn hens, 85 wk of age, were placed in individual cages and assigned randomly into 7 dietary groups of 8 birds each. A control diet, diets containing 5, 10, and 15% SM and diets containing 5, 10, and 15% TSM were prepared. Diets and water were given ad libitum during the 30-d experimental period. Hen-day egg production, egg mass, feed intake, and feed conversion ratio (FCR) were deteriorated with increasing levels of the SM in the diets (P < 0.05). In contrast, these parameters were unchanged with increasing levels of the TSM in diets and compatible with the control group. No significant improvements were observed in exterior or interior egg quality among the dietary groups, except for eggshell weight, strength and yolk color, which were significantly increased in SM and TSM groups when compared to the values in control group (P < 0.05). It is concluded that inclusion of TSM up to 15% in laying hen diets may have beneficial effects on laying performance along with improved eggshell quality and yolk color, and suggested that TSM is a promising combined source of protein and calcium in aged laying hens.     

Influence of graded levels of calcium and vitamin K in the diets of laying hens during the growing phase and their effects on the laying phase

The aim of this study was to evaluate the effect of dietary supplementation of vitamin K (vit K) and Ca in the diets of laying hens on bone and blood parameters and performance during the growing phase and the effects on the laying phase up to 32 weeks. The study utilized 120 Hy‐Line W‐36 pullets in the growing phase (13–18 weeks), 80 laying hens in the production phase (20–32 weeks), distributed in a completely randomized design in a 2 × 5 factorial arrangement, two levels of Ca (0.8 and 1.4%) and five levels of vit K supplementation (0, 2, 8, 16 and 32 mg/kg) with four experimental units. An experimental diet was fed during the growing phase, and the commercial diet was fed during the production phase and were analysed for biochemistry and bone variables at 18 and 32 weeks. In pullets, a significant interaction of levels of vit K and Ca was observed for total serum calcium (mg/dl), Seedor index, Ca in the bones (%) and medullary bone (%). Pullets at 18 weeks of age, receiving diets with 1.4% Ca, displayed a quadratic effect of vit K with better results for these variables with 17.86, 14.59, 14.48 and 16.80 mg/kg of vit K, respectively. For level 0.8% Ca no effect of vit K was observed. The treatments during the growing phase had no effect on egg production, performance and biochemistry serum until 32 weeks. Medullary bone (%), there was a significant interaction for 1.4% Ca and a quadratic effect for vit K, with greater medullary bone areas observed with 6.09 mg/kg vit K in the diet. Supplementation with vit K in a diet with 1.4% Ca during the growing phase allowed for an increase in the area of medullary bone at 18 weeks, which was maintained until 32 weeks.     

The effects of phytase and xylanase supplementation on performance and egg quality in laying hens

ABSTRACT

1. The aim of this study was to evaluate the effects of phytase and xylanase and their interaction on laying hen performance, egg quality, phosphorus (P) digestibility, phytate breakdown, volatile fatty acid (VFA) production and peptide YY concentration.

2. Two hundred and forty hens were allocated to cages at 22 weeks of age based on a 3 × 2 arrangement with phytase (0, 300 or 1500 FTU/kg) and xylanase (0 or 12 000 BXU/kg) as factors.

3. Phytase increased hen-day production (P < 0.05), daily egg mass (P < 0.05) and P digestibility with increasing levels of phytase (P < 0.001). Phytase fed at 1500 FTU/kg reduced IP6 and IP5 and increased myo-inositol concentration in gizzard digesta (P < 0.05). Phytase fed at 300 FTU/kg reduced IP6 in ileal digesta (P < 0.05); however, IP6 and IP5 were further reduced and myo-inositol increased when phytase was added at 1500 FTU/kg (P < 0.05).

4. Xylanase improved feed efficiency when phytase was fed at 300 FTU/kg (P < 0.05). In the absence of phytase, xylanase reduced dry matter and Ca digestibilities (P < 0.05).

5. Neither phytase nor xylanase had an effect on peptide YY or caecal VFA concentrations.     

不同脂肪来源和水平对高温条件下蛋鸡生产性能和蛋品质的影响

文章旨在研究高温条件下日粮添加不同脂肪来源和水平对蛋鸡生产性能和蛋品质的影响。试验将480只31周龄的海兰褐壳蛋鸡随机分为5组,每组4个重复,每个重复24只。对照组日粮代谢能含量为2800 kcal/kg,不添加脂肪,其他4组日粮分别添加2%或4%动物脂肪或大豆油,所有日粮中的能量和营养浓度保存一致,试验共进行28 d,试验期间室内平均温度和湿度分别为(26.7±1.52)℃和(77.4±4.50)%,热应激指数约为76。结果发现:日粮添加2%或4%动物脂肪的蛋鸡体重显著高于对照组和大豆油组(P<0.05),动物脂肪或大豆油组较对照组显著提高蛋鸡体增重(P<0.05),同时日粮中添加脂肪的蛋鸡采食量显著高于对照组(P<0.05)。与对照组相比,4%大豆油组蛋壳厚度显著降低(P<0.05),而日粮中添加4%大豆油较4%动物脂肪显著降低了蛋黄颜色(P<0.05)。结论:在能量和营养水平保持不变情况下,日粮中添加油脂(动物脂肪或大豆油)对在高温条件下饲养的蛋鸡有降低体重损失的作用。但日粮中添加脂肪会降低蛋壳厚度和蛋黄颜色。     

维生素E对免疫抑制产蛋鸡生产性能和蛋品质的调控效应

试验探讨维生素E对免疫抑制蛋鸡生产性能和蛋品质的调控效应,选取健康的尼克褐产蛋鸡270只,随机等分为5组,每组3个重复,每重复18只。第Ⅰ组为对照组,第Ⅱ~Ⅴ组为免疫抑制组,对第Ⅱ~Ⅴ组鸡在试验第5、6、7 d进行腿部肌肉注射80 mg/kgBW环磷酰胺(CTX),第Ⅰ组注射等量生理盐水。Ⅰ、Ⅱ组饲喂基础日粮(维生素E含量44.59 mg/kg),Ⅲ、Ⅳ、Ⅴ组在基础日粮中分别添加50、100、200 mg/kg维生素E。结果显示:①免疫抑制产蛋鸡的产蛋率、平均蛋重和平均日采食量显著降低(P<0.05),破蛋率显著升高(P<0.05)。基础日粮中添加50 mg/kg维生素E显著提高免疫抑制产蛋鸡的产蛋率、平均蛋重和平均日采食量(P<0.05),但仍低于对照组Ⅰ(P<0.05);显著降低料蛋比和破蛋率(P<0.05)。②免疫抑制产蛋鸡的蛋壳厚度、蛋壳强度和哈氏单位显著降低(P<0.05),蛋形指数和蛋黄颜色无显著改变(P>0.05);50 mg/kg维生素E添加量显著提高免疫抑制产蛋鸡的蛋壳厚度、蛋壳强度和哈氏单位(P<0.05),与对照组Ⅰ无显著差异(P>0.05)。因此,免疫抑制显著降低产蛋鸡的生产性能和蛋品质;基础日粮中添加维生素E对免疫抑制蛋鸡的生产性能和蛋品质具有明显的调控效应,且以50 mg/kg添加量效果较好。     

The effects of dietary calcium iodate on productive performance,egg quality and iodine accumulation in eggs of laying hens

The aim of this study was to examine the effects of various levels of supplemental calcium iodate (CI) on productive performance, egg quality, blood indices and iodine (I) accumulation in the eggs in commercial laying hens. A total of 240 White Leghorn layers (Hy‐line W36) were divided through a completely randomized design into six treatments with five replicates and eight hens per each at 32 weeks of age. This experiment lasted for 12 weeks. Concentrations of I in the mash diets were 0.74, 3.13, 5.57, 8.11, 10.65 and 12.94 mg I/kg of feed in treatments 1–6 respectively. The added doses of CI were included 0.0 (control), 2.5, 5.0, 7.5, 10.0 and 12.5 mg/kg of diet for treatments 1–6 respectively. There were no significant differences in productive performance among the treatments. The highest eggshell strength was observed in group fed diet containing 3.13 mg I/kg (p = .014). The highest percentage of calcium and lowest percentage of phosphorus in eggshell were observed in group fed diet containing 12.94 mg I/kg (p = .0001). Feeding hens with diet containing 12.94 mg I/kg increased serum triiodothyronine‐to‐thyroxine ratio (p = .0001). Serum alanine aminotransferase activity in hens fed diet containing 12.94 mg I/kg was significantly more than control (p = .041). Blood Serum triglycerides in hens fed diet containing 8.11 mg I/kg were significantly higher than control (p = .0001). Edible fraction of the eggs of birds fed diet containing 12.94 mg I/kg was enriched by I almost 3 times more than those fed diet containing 0.74 mg I/kg. The results suggested that egg production, egg mass, feed intake and feed conversion ratio were not significantly affected by dietary I levels. Iodine accumulation in the eggs were increased by increasing dietary I levels and the level of 10 mg/kg CI could supply I enrichment of the eggs.     

饲料中添加白术多糖对林下养殖绿壳蛋鸡生产性能与蛋品质的影响

为研究饲料中添加白术多糖对林下养殖绿壳蛋鸡生产性能与蛋品质的影响,试验选用28周龄产蛋的东乡黑羽绿壳蛋鸡540只,随机分为3组,每组3个重复,每个重复60只,1组为对照组饲喂基础日粮,试验2、3组分别在基础日粮中添加2.5%、5.0%白术多糖,预饲期7 d,试验期28 d。在试验期间,测定林下养殖绿壳蛋鸡生产性能和蛋品质。结果表明:(1)试验3组产蛋率和平均蛋重分别较对照组提高7.33%、6.26%(P <0.05);试验3组料蛋比较对照组降低12.64%(P <0.05);试验2、3组的商品合格率、日产蛋量、日均采食量均高于1组,差异不显著(P> 0.05)。(2)试验3组蛋质量、哈夫单位、蛋壳厚度分别较对照组提高5.63%、3.02%、6.12%(P <0.05);试验2、3组的蛋形指数、蛋黄颜色、蛋黄比例均高于1组,差异不显著(P> 0.05)。综上所述,在基础饲料中添加5.0%白术多糖可以提高林下养殖绿壳蛋鸡生产性能与蛋品质。     

复合型抗应激添加剂对夏季蛋鸡产蛋性能、蛋品质及血清生化指标的影响

为了研究复合型抗应激添加剂对夏季蛋鸡产蛋性能、蛋品质及血清生化指标的影响,试验选用120只42周龄伊莎褐蛋鸡,随机分为2组,每组设6个重复,每个重复lO只;对照组饲喂基础日粮,试验组饲喂基础日粮＋80mg／kg复合型抗应激添加剂——禽专用添佳安肽,试验期为60d。结果表明：与对照组相比,试验组产蛋率显著提高5．56％（P〈0．05）,料蛋比显著降低4．74％（P〈0．05）,但对采食量和平均蛋重无显著影响（P〉0．05）;试验组蛋壳强度显著提高15．27％（P〈O．05）,但对蛋壳厚度、蛋白高度、哈夫单位无显著影响（P〉0．05）;试验组血清皮质醇水平显著下降53．91％（P〈0．05）,T_3、T_4水平分别显著下降20．12％、23．57％（P〈0．05）,尿素氮水平显著下降35．35％（P〈0．05）,但对血糖水平无显著影响（P〉0．05）。说明蛋鸡日粮中添加复合型抗应激添加剂——禽专用添佳安肽,具有显著抗热应激效应和增加蛋鸡采食量的作用。     

The effects of environmental enrichment and transport stress on the weights of lymphoid organs,cell‐mediated immune response,heterophil functions and antibody production in laying hens

The effects of environmental enrichment and transport stress on the immune system were investigated in laying hens. A total of 48 1‐day‐old chickens were used, half of the chickens were reared in conventional cages (RCC) and the rest in enriched cages (REC). Transport stress was applied in the 17th week. Liver weight decreased, spleen and bursa of Fabricius weights, white blood cell count, CD4+ and CD8+ cell proportions increased due to the transport. Environmental enrichment significantly increased antibody production and tended to increase monocyte percentage and CD8+ cell proportion. The effect of transport on, heterophil (H) and lymphocyte (L) percentages was not significant in RCC chickens. While heterophil percentage and H:L ratio increased, lymphocyte percentage decreased in REC chickens subjected to transport. Transport stress increased heterophil functions both in REC and RCC chickens, but the increase was higher in REC hens than in RCC hens. In conclusion, although environmental enrichment did not neutralize the effect of transport on lymphoid organs, it activated the non‐specific immune system, cellular and the humoral branches of the specific immune system by increasing heterophil functions, CD8+ cells and antibody production, respectively. Therefore, environmental enrichment suggested for improving animal welfare may also be beneficial to improve the immune system of birds exposed to stress.     

Rare earth element‐enriched yeast improved egg production and egg quality in laying hens in the late period of peak egg production

The objective of this study was to determine the effects of rare earth element‐enriched yeast (RY) on egg production, coefficient of total tract apparent digestibility (CTTAD), egg quality, excreta gas emission and excreta microbiota of laying hens. A total of 216 ISA brown laying hens of 52 weeks of age were used in a 5‐week feeding trial and data were collected every week. Birds were randomly allotted to three dietary treatments each with six replicates and 12 hens per replicate. Each cage (38 cm width × 50 cm length × 40 cm height) contained one hen. Treatments consisted of corn–soya bean meal‐based diet supplemented with 0, 500 or 1000 mg/kg of RY. From weeks 55 to 56, inclusion of RY linearly increased (p < 0.05) egg production. The CTTAD of nitrogen was increased (linear, p < 0.05) with increasing dietary level of RY. In week 55, yolk height and Haugh units were increased linearly (p < 0.05) with increasing dietary RY content. However, no significant effects were observed in terms of excreta emissions and excreta microbiota in laying hens. In conclusion, dietary supplementation with RY improved egg production and CTTAD of nitrogen and slightly improved egg quality in laying hens of the late period of peak egg production.