Effects of Desmodium uncinatum Leaf Meal in the Diet on Lohmann Brown Hens’ Laying Performance and Eggs Quality

A cheap, safe and available alternative protein source to soybean is a huge priority for the developing world. This study is aimed at evaluating the effects of Desmodium uncinatum leaf meal incorporation levels in the diet on Lohmann Brown hens’ laying performances. For this purpose, 60 Lohmann Brown hens aged 33 weeks with an average weight of 1.78 kg were randomly assigned to 3 treatment groups of 20 birds each with 4 replicates. The experimental treatments consisted of DULM 0, DULM5, and DULM10 containing 0, 5 and 10 kg of D. uncinatum leaf meal (DULM) per 100 kg of feed respectively. The results reveal that except for the weights of hens, laying performances were significantly affected (p < 0.05) by DULM in the diet. Daily feed intake was lower with 10% incorporation of DULM in the diet as compared to a diet with 5% DULM which recorded the highest value for this parameter. Moreover, the highest value for the egg weight, egg mass, yolk index, albumen index and egg production were recorded with diet DULM5. On the other hand, the diet with 10% of DULM (DULM10) recorded the highest relative shell weight, feed conversion ratio and egg price. Nevertheless, the mortality rate found in this study was 0% for all treatments confirming the good quality of DULM as protein feedstuff for layer. It was concluded that incorporation levels of D. uncinatum leaves at 5% in the diet improved the laying performances of Lohmann Brown hens.

Effects of Fermentation Product Containing Phytase on Productive Performance,Egg Quality,and Phosphorous Apparent Metabolism of Laying Hens Fed Different Levels of Phosphorus

This study investigated the effects of fermentation product containing phytase （FPP） that was fermented using waste vinegar residue （WVR） as substrate from Aspergillusficuum NTG-23 on productive performance, egg quality, and phosphorus apparent metabolism of laying hens. First, 375 22-wk-old Jinghong hens were allocated into 5 treatments （5 replicates of 15 hens each） in an 8-wk experiment for evaluating the parameters of productive performance, egg quality, serum, and tibia. Experimental diets contained 4% FPP and 96% corn-soybean diet. The levels of dicalciurn phosphate （DCP） were 1.34, 1.01, 0.67, 0.34 and 0%. Next, thirty 31-wk-old Jinghong hens were fed 5 types of diets for evaluating phosphorous apparent metabolism rate. Egg productive rate, egg weight, feed conversion ratio, Haugh unit, egg albumen height, serum calcium, tibia ash, tibia ash calcium and tibia breaking strength were not different significantly among 5 treatments. The significant difference of average daily feed intake was not appeared when the DCP content of corn-soybean-FPP diet was reduced to 0.67%; the eggshell hardness, eggshell thickness and serum phosphorus were not reduced significantly until the DCP content of corn-soybean-FPP diet was reduced to 0.34%. The yolk color was improved when the laying hens fed deficient DCP corn-soybean-FPP diet. A 22.14% reduction in excreta phosphorus was observed when the laying hens fed low phosphorus （0.67% DCP） corn-soybean-FPP diet. A 30% elevation of phosphorus apparent metabolism rate was obtained when the DCP content of corn-soybean-FPP diet was decreased from 1.34 to 1.01%. The reducing cost of layer diet was totalized about 120 CNY 1000 kg1 diet when the content of DCP was 0.67% in corn-soybean-FPP diet. These results indicated that FPP could be applied in laying hen as a potential, cost-effective and rational application of WVR.

The Effect of Varied Dietary Crude Protein Levels with Balanced Amino Acids on Performance and Egg Quality Characteristics of Layers at First Laying Phase

Four diets were formulated to study the influence of varying crude protein levels on the performance, egg quality, serum and haematological characteristics at the first phase of laying cycle of sixty Bovan Nera laying birds that were randomly allotted to dietary treatments. The four experimental diets had five replicates each and three birds per repli-cate. Diet 1 contained 14% crude protein (CP), while diet 2 contained 15% CP, diets 3 and 4 contained 16% and 17% CP respectively. The experimental birds were fed for 10 weeks and the data collected were statistically analysed. Apparent variations recorded for all the performance characteristics such as Egg number, Hen-day production, Feed Conversion Ratio (FCR) and weight gain were significantly different (p < 0.05). The best FCR value were recorded by birds fed 17% CP (3.45), while the highest weight gain mean value were also recorded by birds fed 17% CP value. Findings indicated a direct relationship between dietary crude protein values and performance.

Why cuckoos should parasitize parrotbills by laying eggs randomly rather than laying eggs matching the egg appearance of parrotbill hosts?

The coevolutionary interaction between cuckoos and their hosts has been studied for a long time, but to date some puzzles still remain unsolved. Whether cuckoos parasitize their hosts by laying eggs randomly or matching the egg morphs of their hosts is one of the mysteries of the cuckoo problem. Scientists tend to believe that cuckoos lay eggs matching the appearance of host eggs due to selection caused by the ability of the hosts to recognize their own eggs.In this paper, we first review previous empirical studies to test this mystery and found no studies have provided direct evidence of cuckoos choosing to parasitize host nests where egg color and pattern match. We then present examples of unmatched cuckoo eggs in host nests and key life history traits of cuckoos, e.g. secretive behavior and rapid egg-laying and link them to cuckoo egg laying behavior. Finally we develop a conceptual model to demonstrate the egg laying behaviour of cuckoos and propose an empirical test that can provide direct evidence of the egg-laying properties of female cuckoos. We speculate that the degree of egg matching between cuckoo eggs and those of the host as detected by humans is caused by the ability of the hosts to recognize their own eggs, rather than the selection of matching host eggs by cuckoos. The case of Common Cuckoos(Cuculus canorus) and their parrotbill hosts(Paradoxornis alphonsianus), where it has been shown that both have evolved polymorphic eggs(mainly blue and white), was used to develop a conceptual model to demonstrate why cuckoos should utilize parrotbill hosts by laying eggs randomly rather than laying eggs matching the appearance of host eggs.In conclusion, we found no evidence for the hypothesis that cuckoos lay eggs based on own egg color matching that of the parrotbill-cuckoo system. We argue theoretically that laying eggs matching those of the hosts in this system violates a key trait of the life history of cuckoos and therefore should be maladaptive.

Effects of dietary phosphorous supplementation on laying performance,egg quality,bone health and immune responses of laying hens challenged with Escherichia coli lipopolysaccharide

Background: Phosphorus is an essential nutrient to maintain poultry health and performance. The objective of this study was to evaluate the effect of dietary phosphorus levels on egg production, egg quality, bone health, immune responses of laying hens challenged with Escherichia coli lipopolysaccharide.Methods: Three hundred laying hens at 28 wk were randomly divided into 2 dietary treatments with 10 replicates of 15 birds. The wheat-soybean based diets contained either 0.12% or 0.4% non-phytate phosphorus(NPP). At 32 wk of age, all the birds of each dietary treatment were injected into the abdomen with 1.5 mg/kg body weight(BW) of either LPS or saline once a day at 24-h intervals for continuous 9 d. The performance of laying hens was evaluated for 9 d. The eggs after the fifth injection were collected to value the egg quality. Three hours after the first injection, blood was collected to measure serum metabolite and immune response associated parameters.Three hours after the fifth injection, the hens were euthanized to obtain tibia, cecal tonsils and jejunum.Results: Compared with saline-injected hens, LPS-injected hens had lower feed intake and egg production(P < 0.05).Eggshell thickness, strength, albumin height and Haugh unit were significantly increased in LPS-injected hens compared with saline-injected hens(P < 0.05). Furthermore, laying hens challenged with LPS had lower villious height/crypt depth ration than those received saline. Serum calcium, phosphorus and SOD activities significantly decreased in the LPS-injected hens compared with the control(P < 0.05). LPS up-regulated expression of IL-1β, IL-6 and IL-10 in cecum, and serum concentration of MDA, IL-1β and IL-6(P < 0.05), whereas 0.40% dietary non-phytate phosphorus supplementation significantly increased(P < 0.05) villi height/crypt depth ratio, decreased(P < 0.05) serum MDA and IFN-γ concentration compared with the 0.12% non-phytate phosphorus group.Conclusion: In summary, this study demonstrates that 0.40% dietary non-phytate phosphorus supplementation significantly increased calcium and phosphorus levels of eggshell, increased villi height/crypt depth ratio, decreased serum MDA and IFN-γ concentration compared with the 0.12% non-phytate phosphorus groups. The results indicate that high level of dietary non-phytate phosphorus exerts a potential effect in alleviating systemic inflammation of LPSchallenged laying hens.

Effect of dietary defatted diatom biomass on egg production and quality of laying hens

Background： This study was to determine if feeding laying hens with defatted diatom microalgal biomass （DFA） from biofuel production affected their egg production and health status. Methods： Five replicates of 5 individually caged ISA Babcock White leghorn hens were fed 4 diets, including a corn-soybean meal control diet, a diet containing 7.5% DFA substituting for soybean meal, and diets containing 7.5% or 15% DFA substituting for corn and soybean meal. Body weights, feed intake, feed conversion ratio （FCR）, rate of egg production, egg size, egg mass, and several characteristics of eggs were determined at 4 and 8 wk. Venous blood was sampled at 4 and 8 wk for measurement of 5 biomarkers of health. Results： The15% DFA diet decreased （P 〈 0.05） feed intake, egg production, and plasma uric acid concentrations as compared with the control diet, but increased （P 〈 0.05） egg albumen weight and height compared with the 7.5% DFA diets. The two levels of DFA produced dose-dependent （P 〈 0.05） changes in three color measures of egg yolk, without affecting four hen plasma biochemical indicators of health. Conclusions： Feeding laying hens with 7.5% DFA in the corn-soybean meal diet for 8 wk had no adverse effect on their health, egg production, or egg quality, but 15% inclusion reduced feed intake, egg production, and efficiency of feed utilization.

Effect of Quercetin on Egg Quality and Components in Laying Hens of Different Weeks

This trial was conducted to evaluate the effect of quercetin on egg quality and components in laying hens of different weeks. A total of 240 healthy Hessian laying hens at 29, 39-week-old with similar body weight and laying rate were randomly divided into four groups with six replicates of 10 each replicate, respectively. The treatments were fed with basal diet supplemented with 0, 0.2, 0.4 and 0.6 g-kg-1 quercetin for 8 weeks. The results showed that compared with the control, broken or soft shell rate significantly decreased at 0.2 and 0.4 g.kg-1 quercetin and eggshell thickness significantly increased at 0.4 g.kg-1 quercetin （P〈0.01） in laying hens at 39-47 weeks old; yolk protein significantly decreased at 0.6 g kg-1 quercetin （P〈0.05） in laying hens at 29-37 weeks old; while yolk protein significantly increased at three quercetin treatments in laying hens at 39-47 weeks old; yolk cholesterol significantly decreased by quercetin in laying hens at 29-37 weeks old （P〈0.05）; yolk total phospholipids significantly increased at 0.4 and 0.6 g kg-1 quercetin （P〈0.01） and yolk cholesterol significantly decreased at 0.6 g kg-1 quercetin （P〈0.05） in laying hens at 39-47 weeks old. In a word, quercetin affected egg quality and components to some extents in laying hens of different weeks, the older the hens became, the better improvement they would be. The optimum level of quercetin was 0.4 g kg-1 in the basal diet.

The Effect of Different Levels of Sesame Oil on Productive Performance, Egg Yolk and Blood Serum Lipid Profile in Laying Hens

Addition of sesame oil into layer diets has been proved to enrich the proportion of polyunsatu-rated fatty acids in animal’s products. In this study, the effects of different levels of sesame oil in the diets on the performance, egg yolk and blood serum lipid profile of Isa Brown laying hens were investigated. A total of 96 layers were assigned into 4 groups to receive either 1 of 4 different diets contained 0.0%, 1.5%, 3.0% and 4.5% sesame oil, respectively. Sample of 12 eggs obtained from each groups were assessed for egg quality. The egg yolk fatty acid profile was determined with gas chromatography. Results revealed that the higher levels of sesame oil in the diet decreased egg production, egg weight, and egg yolk color except feed conversion ratio. In addition, supplementation of sesame oil increased the flow index of the eggs and the Haugh unite. The egg yolk lipid profile was not significantly different in the sesame oil fed groups, whereas, compare to control, it decreased the level of cholesterol. The blood serum lipid profile decreased in the sesame oil groups compare to control group. Meanwhile, monoacildigliserol also decreased in the sesame addition groups. In parallel with increasing levels of sesame oil, monounsaturated fatty acid (oleic acid) in the egg yolks significantly increased compared to the control (37.00%, 42.89%, 42.20% and 43.48%, respectively). It can be implied that sesame oil supplementation into the laying hens diet is necessary to produce monounsaturated fatty acid (MUFA) enriched eggs.

Effects of Different Facilities on Laying Performance,Egg Quality and Air Quality for Layers Under Free Range System

[ Objective] This paper aimed to study the effects of different facilities on laying performance, egg quality and air quality for commercial layers under free range system. [Metbod] The single factorial arrangement was used in the tdal. 2 800 commercial Beijing You Chicken （BYC） at 23 weeks of age were chosen and randomly divided into four groups, three replicates each group, and 210 birds each replicate. The layers lived in loose housing condition with deep litter inside. Group 1 was the control, equipped with standard laying boxes, and flat-type perches; group 2 was e- quipped with common laying boxes, and flat-type perches; group 3 was equipped with common laying boxes, and erect-type perches, and group 4 was equipped with standard laying boxes, and erect-type perches. The laying performance, laying position and egg quality of birds during 24 to 32 weeks of age were recorded and measured, and average NH3, CO~ concentration of each group at 32 weeks of age were measured and detected. [Result] The results showed that laying performance of commercial BYC under loose housing condition were significantly different during 24 -32 weeks of age. The laying rate of the control group equipped with flat-type porches and standard laying boxes （33.25%） was significantly higher than in group equipped with flat-type perches and common laying boxes （21.83%） （P〈0.05）, and other two groups （26.04% and 27.48%） （P 〈0.05）. The ratio of floor eggs was significantly lower in groups with standard laying boxes than in the groups with common laying boxes （P 〈0. 05）, and the laying proportion in the first floor of layer boxes were much higher than those in the second floor （ P 〈 0.05）. There were no significant differences on egg quality among the groups （P〉0.05）. Average NH3, CO2 concentration of group 3 and 4 at 82 weeks of age were both signifi- cantly higher than of group 1 and 2 （P 〈0.05）. [ Conclusion] All of the above indicated that the utilization of facilities could improve layer＇s laying rate, especially with flat-type perches and standard laying boxes, and the indoor air quality was also affected to some extent.

Effect of Dietary Mulberry Leaves on Productive Performance,Egg Quality and Blood Biochemistry in Laying Hens

[Objective] The aim was to provide more information about the possible use of mulberry leaves in hen diets.[Method] Two hundred ninety two Hyline Gray laying hens, 48 wk old, were randomly allotted into four groups with 73 chickens per group. Each group was fed for 6 wk with diets that contained dried mulberry leaves at 0, 5, 10, or 15%. [ Result] The rate of egg production, egg weight, egg mass, feed intake, body weight, blood glucose level, total blood cholesterol, and triglyeride, and cholesterol of egg yolk in the dietary mulberry leaf groups were lower than the 0% mulberry leaves group. Compared with the 0% group, the feed required to produce 1 kg of eggs was 12.8% more in the 15% dietary mul- berry leaf group. Body weight and cholesterol of egg yolk decreased significantly in this group （P 〈0.05）. Blood glucose and triglyerides in the 15% dietary mulberry leaf group were significantly lower than in the 0 and 5% dietary mulberry leaf groups （P 〈0.05）. Yolk color in all treatments was higher than in the 0% group （P 〈0.05）, and Roche pigmentation score increased by 2 -2.9. One -deoxynojirimycin was detected from egg white in all treatments, and its content varied significantly between groups （ P 〈0.05）. E Conclusion] This study reflected the hypoglycemic and lipid -low- ering effects of mulberry leaves on productive performance and egg quality in laying hens. The suggested proportion of dietary mulberry leaves was 5% -10%.

Effects of Xylooligosaccharide(XOS)and Probiotics(PRO)on Production Performance,Egg Quality and Intestinal Short-chain Fatty Acids of Laying Hens in Late Laying Period

[Objective]The paper was to study the effects of xylooligosaccharide(XOS)and probiotics(PRO)and their interaction on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period.[Method]A total of 36074-week-old Romain brown laying hens were randomly divided into four groups,six replicates each group and 15 chickens each replicate.The trial lasted 63 d.The laying hens in control group(CON)were fed with basal diet,and those in experimental groups were fed with the basal diets adding with 150 mg/kg XOS(XOS group),100 mg/kg probiotics(PRO group),150 mg/kg XOS+100 mg/kg probiotics(XOS-PRO group).[Result]Compared with the control group,the laying rate,daily egg production,yolk ratio,colonic acetic acid and caecal propionic acid in XOS group increased significantly(P<0.05),and the feed gain ratio decreased remarkably(P<0.05).PRO had no significant effect on the production performance and egg quality of laying hens in late laying period(P>0.05),but significantly increased colonic acetic acid(P<0.05).XOS and PRO had no interaction effect on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period(P<0.05).[Conclusion]Adding XOS to the diet of laying hens in late laying period could increase the content of short-chain fatty acids in the hindgut of laying hens,and effectively improve the production performance and egg quality of laying hens in late laying period.Adding PRO to the diet did not significantly improve the production performance and egg quality of laying hens,and there was no interaction effect between XOS and PRO.

A Combination of Wheat Bran and Vegetable Oils as Feedstuff in Laying Hens’Diet:Impact on Egg Quality Parameters

Wheat bran (WB) is an important side product of the milling industry and plays an increasing role in animal feeding. Despite its nutritional value, its application is limited as a result of its pronounced fiber content. Taking into account the potential use of WB supplementation in feed for laying hens thereby replacing human edible foodstuffs, the influence of different WB levels (0 g·kg-1, 75 g·kg-1, and 150 g·kg-1) combined with sunflower or rapeseed oil on egg quality was studied. Among the egg-related quality parameters investigated, eggshell cleanliness, shell rigidity, egg weight, haugh units, yolk and albumen mass, color, pH value, dry matter, crude protein, crude ash, fatty acid spectrum, cholesterol and α-tocopherol of the yolk were monitored. No negative effect of WB supplementation was observed in terms of egg weight, shell weight, albumen weight, yolk weight, haugh unit, shell thickness and eggshell breaking strength. However, certain parameters (i.e. α-tocopherol content, Σn-3 PUFA) were enhanced by feeding 75 g·kg-1 and 150 g·kg-1 WB. The use of WB (75 g·kg-1 and 150 g·kg-1) had no negative effect on egg quality and can, therefore, be recommended for laying hen diets up to 150 g·kg-1. Additionally, the application of rapeseed oil high in Σn-3 PUFA resulted in yolks exhibiting a low Σn-6 PUFA/Σn-3 PUFA ratio.

Last but not the least: effects of laying sequence on egg color variation and embryonic development of Russet Sparrow(Passer cinnamomeus)

Background: Laying sequence has important effects on eggshell color and embryonic development in birds. Some birds can allocate resources unevenly among the eggs within a clutch, prioritizing those at the beginning of the laying sequence, in order to maximize reproductive success. The changes in egg color according to laying sequence may be an adaptation to pressure from predators or brood parasites.Methods: In this study, effects of laying sequence on egg color and embryonic heart rate in Russet Sparrows(Passer cinnamomeus) were investigated using artificial nest boxes. The eggs were divided into three groups: first to be laid, intermediate in the laying sequence, and last to be laid. We maintained the eggs in an incubator and measured embryonic heart rates.Results: Avian visual modeling showed that the background color brightness of the last eggs laid was significantly higher(whiter) than those of the other eggs. All eggs were about the same size and hatched around 13 days, indicating that laying sequence significantly affected embryonic development speed; the last eggs to be laid developed significantly faster than did the first in the clutch.Conclusions: Our study quantified the effect of laying sequence on egg color variation and proved that laying sequence has an important effect on embryonic heart rate in Russet Sparrows.

Correlation Between Cholesterol Content in Egg Yolks and Laying Rate

[Objectives]This study was conducted to investigate the relationship between cholesterol content in egg yolks and laying rate of laying hens.[Methods]Forty eight 450-day-old Hyline brown hens with uniform weight were randomly divided into 4 groups with 3 replicates in each group and 4 individuals in each replicate.Group 1 as the control check group(CK)was fed the basal diet;group 2 was fed the basal diet with the addition of 150 g/t of probiotics;group 3 was the basal diet+200 g/t lipase group;and group 4 was fed the basal diet with the addition of 150 g/t of probiotics and 200 g/t of lipase.The preliminary trial period was 10 d,and the experimental period was 30 d.[Results]The cholesterol content in the egg yolks of each test group was higher than that of the control group at 14 and 28 d after the drug administration.The laying rate of each test group began to increase at 14 d after the drug administration;and the laying rate of each test group increased significantly 28 d after the drug administration.It indicated that with the increase of cholesterol in egg yolks,the laying rate of laying hens increased significantly.[Conclusions]This study provides a certain experimental basis for culture production of laying hens.

Effects of Green Forage on Production Performance and Egg Quality of Suyou No.1 Laying Duck

[ Objective ] The paper was to study the effects of green forage on production performance and egg quality of laying ducks. [ Method] According to one- factor randomized complete experimental design, 200 healthy Suyou No. 1 laying ducks aged 200 days were randomly divided into five groups, four repeats each group, and each repeat contained 10 laying ducks. Parts of formulated feed in groups I - IV were replaced with different types and quantities of green forage, and group V was set as control. The trim lasted for 42 d. [ Result] Replacing parts of formulated feed with green forage could improve the production performance of laying ducks （P 〉 0.05 ）, and the economic benefits also increased. For egg quality, Haugh unit was improved （ P 〉 0.05 ） ; yolk color increased significantly ; compared to control group, yolk color was significantly increased in groups with 100 g chicory and 70 g clover （P 〈0.05 ）, and was extremely increased in the group with 100 g clover （P 〈0.01 ）. [ Conclusion] The group with 100 g chicory had the best effect on production performance of laying ducks, and the group with 100 g clover had the best coloring effect on yolk.

The Effect of Feeding Laying Hen Conventional and Omega-3 Enriched Diet on Fatty Acid Profiles in Egg Yolk Lipids

The aim of this research was to enrich table eggs with n-3 polyunsaturated fatty acids （n-3 PUFA）, especially with essential eicosapentaenoic acid （EPA） and docosahexaenoic acid （DHA）. After five weeks of feeding of laying hens with standard and experimental diets, there was analysis carried out to determine the fatty acid profile in egg yolks of both groups. Omega-3 eggs contain statistically significantly （P 〈 0.05） less sum of saturated fatty acids （∑SFA） and more∑n-3 PUFA, as well as narrower ratio of∑n-6/∑n-3 PUFA than conventional eggs. If referring to individual fatty acids of omega-3 eggs, there were increased portions （P 〈 0.05） of α-linolenic acid （α-LNA）, docosapentaenoic acid （DPA）, EPA and DHA determined in this research, which was in line with the research objective. Within the presented research, concentration of n-3 PUFA in egg yolk lipids of experimental group was two times higher than that in the control group. The ratio of ∑n-6 PUFA/∑n-3 PUFA was reduced from 12.04 to 6.17. Within their enzymatic system, laying hens can act as a bioreactor to naturally enrich their eggs with n-3 PUFA, especially with EPA and DHA. The results of this research proved that the fatty acid profile can be modified by designing of laying hens＇ diets with specific forages. Eggs were enriched with favorable fatty acids in the following order： α-LNA 〉 DHA 〉 DPA 〉 EPA.

Fermented soybean meal improved laying performance and egg quality of laying hens by modulating cecal microbiota,nutrient digestibility,intestinal health,antioxidant and immunological functions

Antinutritional factors in feedstuffs may limit their utilization in livestock production,but fermentation process can be used to improve feed quality;however,studies on fermented soybeans for laying hens remain limited.We investigated the effect of fermented soybean meal(FSBM)at various inclusion levels as a partial replacement for soybean meal(SBM)on egg production,egg quality,amino acid digestibility,gut morphology and microbiota,antioxidant capacity and immune response of young laying hens.A total of 360 Hy-line Brown laying hens aged 18 weeks were selected and divided into 5 groups of 6 replicates each and 12 birds per replicate.The control group received a basal diet while the trial group received the basal diet with FSBM included at 2.5%,5.0%,7.5%and 10.0%,respectively,for 12 weeks.Our findings revealed that the nutritional value of FSBM was higher compared to that of SBM in terms of reduced content of trypsin inhibitors and increased contents of crude protein,amino acids and minerals.FSBM enhanced egg production(P<0.05),feed-to-egg ratio(P<0.05),and albumen quality(albumen height and Haugh unit)(P<0.05).Furthermore,FSBM improved apparent fecal amino acid digestibility(P<0.05),gut morphology(increased villus height,villus width,villus height-to-crypt depth ratio and decreased crypt depth)(P<0.05),antioxidant capacity(reduced malondialdehyde and increased catalase,total superoxide dismutase,glutathione peroxidase and total antioxidant capacity)(P<0.05)and immune function(increased concentrations of IgG,IgA,and IgM;increased levels of transforming growth factor beta and Toll-like receptor 2;and reduced levels of interleukin 1βand tumor necrosis factor alpha)(P<0.05).Further analysis showed that FSBM altered the composition of the gut microbiota favoring beneficial microbes.These findings suggest that probiotic fermentation improved the nutritional value of SBM.The inclusion of FSBM in the diets of laying hens at 2.5%or 5.0%improved amino acid digestibility,gut health,immune function,egg production and egg quality.

Experimental evidence that cuckoos preferentially parasitize host nests early in their laying cycle

Brood parasites,such as the Common Cuckoo(Cuculus canorus),rely on manipulating hosts from other species to raise their offspring.Selection should favor individuals that are able to identify and choose host nests that closely match the incubation stage of their own eggs.While intuitive,and supported by the findings of numerous longterm monitoring studies,experimental evidence of this remains sparse.By using video monitoring,we used three experimental groups to explore whether Common Cuckoos preferentially choose host Oriental Reed Warbler(Acrocephalus orientalis)nests that are early in their laying cycle.We found that Common Cuckoos preferentially parasitize nests of the host Oriental Reed Warbler that are earlier in their laying(less vs.more eggs)or nesting cycle(eggs vs.chicks),and videos of our experiments provide direct insights into their decision making process.Our results provide strong experimental evidence that Common Cuckoos are able to assess nesting stage and strategically choose nests that increase the likelihood of successful parasitism.

Application of Several Additives Instead of Antibiotics in the Production of Laying Hens

[ Objective ] The test was conducted to study the effect of three different additives instead of antibiotics in the production of laying hens. [ Method ] Basal diets in four test groups were added with 0. 015 % oxytetracycline, 0. 01% microecological preparation, 0.2% fulvic acid, and 0. 1% Chinese herbal medi- cine extract respectively, and laying hens in control group were fed with basal diets. Effect of four different additives on performance and egg quality were studied under the temperature of 28.6℃. [ Result] The average egg-laying rate and feed-egg ratio in groups 2, 3 and 4 were significantly better than those in control group and group 1 （P 〈 0.05 ）. The contents of fat and cholesterol in eggs in groups 2, 3 and 4 were lower than those in control group and group 1. And the fat content of eggs in group 4 was 13.42% lower than that in control group, the difference was significant （ P 〈 0.05 ）. The protein contents in groups 2, 3 and 4 were signifi- cantly higher than those in control group and group 1 （P 〈 0.05 ）. [Condusion ] Microecological preparation, fulvic acid and Chinese herbal medicine extract could replace antibiotics to be applied in the production of laying hens.

Effects of Dietary Betaine on Production Perform-ance,Egg Quality and Serum Biochemical Indexes of Layers under Heat Stress Condition

[ Objective ] This experiment was conducted to study the effects of dietary betaine on peiformance, egg quality and serum biochemical parameters of lay- ing hens under heat stress condition. [ Method] A total of 600 22-week-old commercial Roman laying hens were randomly divided into five groups, with eight repli- cates in each group and 15 hens in each replicate. Group I was taken as the positive control group, and laying hens in group ] were fed with basal diets in anrmal thermal environment. Temperature humidity index of group 1 was between 64.9 and 68.9. Group II was taken as the negative control group, and laying hens in group II were fed with basal diets under heal stress condition. Temperature humidity index of group II was higher than 72. laying hens in groups llI-V were fed with basal diets supplemented with 200,400 and 600 mg/kg betaine under heat stress condition respectively, and temperature humidity indexes in groups III-V were all higher than 72. The experiment lasted for 14 weeks. [ Results ] Results showed that there were no significant differences in average daily feed intake, feed egg ratio and broken egg rate among different test groups （P 〉 0.05 ）. Hen-housed laying rate, hen-housed egg yield, serum total protein （TP） content and serum alkaline phosphatase （AKP） activity in group II were significantly lower than those in group I（ P 〈0.05 ）. However, activities of glutamic-oxalacetic transaminase （GOT）, creatine kinase （CK） and glutamic-pyruvic transaminase （GPT） in group II were significantly higher than those in group i （P 〈0.05 ）. Hen-housed laying rate, hen-housed egg yield and serum TP content in group IV were significantly higher than those in group II（ P 〈 0.05 ）. Hen-housed egg yield, serum TP eontent and serum albumin （ALB） content in group V were significantly higher than those in group II（P 〈0.05）. Activities of serum CK and Girl in groups IV and V were significantly lower than those in group II （ P 〈 0.05 ）, serum triglyceride （TG） content in group V was significantly lower than that in group 11 （ P 〈 0.05 ）. [ Conclusion] Metabolism and physiological function of laying hens could be affected by heat stress, and which caused a decline in performance. Adding of dietary betaine in diets could improve hen-housed egg production and hen-housed laying rate, which could also improve the health of laying hens under heat stress condi- tion. The appropriate dietary adding content of betaine was 400 mg/kg.