Characterisation of undigested components throughout the gastrointestinal tract of broiler chickens fed either a wheat-or maizebased diet

This study was to characterise the undigested nutrients present along the gastrointestinal tract of birds offered common wheat-or maize-based diets, with the goal of optimising utilisation of enzymes to enhance digestive efficiency. Wheat-and maize-based diets were offered to 240 mixed-sex broilers(10birds/pen; n = 12) from 1 to 35 d post-hatch. Digestibility of dry matter, starch, crude protein and nonstarch polysaccharides(NSP) were measured in the crop, gizzard, duodenum, jejunum, ileum, caec...     

猪和肉鸡胃肠道中植酸降解模式的最新研究进展

被用作猪和家禽饲料的植物原料含有肌醇1,2,3,4,5,6-六磷酸二氢(myo-inositol 1,2,3,4,5,6-hexakis dihydrogen phosphate,InsP6)及其作为磷(Phosphorus,P)主要储存形式的盐(植酸盐)。磷从InsP6中释放出来的程度在很大程度上决定了植物原料中磷的消化率和满足动物对磷需求所需的矿物磷酸盐的量。植酸酶和其他磷酸酶能够在动物消化道中催化InsP6水解,并且参与的酶源自日粮和内源性起源的一个混合物,后者由肠上皮和侵入消化道的微生物产生。猪和肉鸡消化道内InsP6的降解程度和出现的降解产物明显不同。植物本身所含植酸酶的活性是影响猪体内InsP6降解和P消化率的一个重要因素,而内源酶的活性在肉鸡体内在含磷原料水解上起主要的作用。肉鸡利用InsP6中磷的能力远高于猪。然而,InsP6的降解很容易通过补充P、钙(Calcium,Ca)和外源植酸酶来控制。虽然在确定引起InsP6降解变化的因素方面已经取得了很大的进展,但是人们对于多种相互作用的理解还不够充分,无法在行业中的饲料配方上加以考虑。在全球的磷矿粉储存量有限、由于土壤磷在某些地区的积累引起的环境问题和较高的饲养成本条件下,更好地理解这些相互作用至关重要。     

猪和肉鸡胃肠道中植酸降解模式的最新研究进展(续1)

被用作猪和家禽饲料的植物原料含有肌醇1,2,3,4,5,6-六磷酸二氢(myo-inositol1,2,3,4,5,6-hexakisdihydrogenphosphate,InsP_6)及其作为磷(Phosphorus,P)主要储存形式的盐(植酸盐)。磷从InsP_6中释放出来的程度在很大程度上决定了植物原料中磷的消化率和满足动物对磷需求所需的矿物磷酸盐的量。植酸酶和其他磷酸酶能够在动物消化道中催化InsP_6水解,并且参与的酶源自日粮和内源性起源的一个混合物,后者由肠上皮和侵入消化道的微生物产生。猪和肉鸡消化道内InsP_6的降解程度和出现的降解产物明显不同。植物本身所含植酸酶的活性是影响猪体内InsP_6降解和P消化率的一个重要因素,而内源酶的活性在肉鸡体内在含磷原料水解上起主要的作用。肉鸡利用InsP_6中磷的能力远高于猪。然而,InsP_6的降解很容易通过补充P、钙(Calcium,Ca)和外源植酸酶来控制。虽然在确定引起InsP_6降解变化的因素方面已经取得了很大的进展,但是人们对于多种相互作用的理解还不够充分,无法在行业中的饲料配方上加以考虑。在全球的磷矿粉储存量有限、由于土壤磷在某些地区的积累引起的环境问题和较高的饲养成本条件下,更好地理解这些相互作用至关重要。     

猪和肉鸡胃肠道中植酸降解模式的最新研究进展(续2)

被用作猪和家禽饲料的植物原料含有肌醇1,2,3,4,5,6-六磷酸二氢(myo-inositol1,2,3,4,5,6-hexakisdihydrogenphosphate,InsP6)及其作为磷(Phosphorus,P)主要储存形式的盐(植酸盐)。磷从InsP6中释放出来的程度在很大程度上决定了植物原料中磷的消化率和满足动物对磷需求所需的矿物磷酸盐的量。植酸酶和其他磷酸酶能够在动物消化道中催化InsP6水解,并且参与的酶源自日粮和内源性起源的一个混合物,后者由肠上皮和侵入消化道的微生物产生。猪和肉鸡消化道内InsP6的降解程度和出现的降解产物明显不同。植物本身所含植酸酶的活性是影响猪体内InsP6降解和P消化率的一个重要因素,而内源酶的活性在肉鸡体内在含磷原料水解上起主要的作用。肉鸡利用InsP6中磷的能力远高于猪。然而,InsP6的降解很容易通过补充P、钙(Calcium,Ca)和外源植酸酶来控制。虽然在确定引起InsP6降解变化的因素方面已经取得了很大的进展,但是人们对于多种相互作用的理解还不够充分,无法在行业中的饲料配方上加以考虑。在全球的磷矿粉储存量有限、由于土壤磷在某些地区的积累引起的环境问题和较高的饲养成本条件下,更好地理解这些相互作用至关重要。     

The effect of hen-egg antibodies on Clostridium perfringens colonization in the gastrointestinal tract of broiler chickens

We evaluated the ability of hen-egg antibodies (HEA) to reduce intestinal colonization by Clostridium perfringens in broiler chickens. Antibodies against C. perfringens or cholera toxin (negative control) were obtained from the eggs of laying hens hyperimmunized using a C. perfringens bacterin or cholera toxin. Eggs were collected, pooled, and egg antibodies were concentrated by polyethylene-glycol precipitation. An initial experiment was conducted to determine the in vivo activity of the administered antibody along the length of the intestine. Thereafter, two feeding trials were performed to assess the efficacy of feed amended with the egg antibodies in reducing the level of colonization of C. perfringens in challenged birds. Antibody activity declined from proximal to distal regions of the intestine but remained detectable in the cecum. In the first experiment there was no significant reduction in the number of C. perfringens in the birds fed the diet amended with the anti-C. perfringens egg antibody, compared to the birds that received the anti-cholera toxin egg antibody (n = 10), at any of the sampling times. In the second experiment there was a significant decrease in C. perfringens intestinal populations 72 h after treatment (n = 15) as assessed by culture-based enumeration, but there was no decrease as measured by quantitative PCR based on the C. perfringens phospholipase C gene. Intestinal-lesion scores were higher in the birds that received the anti-C. perfringens HEA. Our work suggests that administration of HEA did not reduce the level of C. perfringens intestinal colonization and conversely might exacerbate necrotic enteritis.     

Performance and gastro-intestinal response of broiler chickens fed on cereal grain-based foods soaked in water.

1. Two experiments were carried out to investigate the addition of 1 3 kg water per kg air-dry mash diets containing high proportions (600 to 700 g/kg) of ground cereal grains (wheat, barley or oats) on broiler performance and the structure and function of the gastro-intestinal tract. 2. Chicks at the age of 7 d were fed on the wheat-, barley- or oats-based diets in the dry or wet forms for 35 d. Food and water intakes were recorded daily while body weight was measured weekly. Two birds from each treatment were killed each week to measure gut size and the viscosity of gut contents. Tissue samples from various digestive segments were histo-morphologically examined to determine the thickness of tissue layers, size of tissue glands, villa heights, crypt depths and thickness of tunica muscularis. Crypt cell proliferation rate (CCPR) for each segment was also determined using a metaphase arrest technique. 3. The results from both experiments showed that wetting food significantly (P<0.05) increased food intake, total water intake and body weight gain of broiler chickens. The body weight gains of birds were proportional to their food intakes so that the efficiency of food utilisation was similar for all treatments. Dry matter retention of food tended to increase in birds given wet food from 7 to 21 d but not thereafter, compared to the dry-fed birds. Although water intake from the water bottle was significantly (P<0.05) reduced in birds given wet food, total water intakes from the water bottle plus that from food were significantly (P<0.05) higher in the wet-fed birds than in the dry-fed birds. The ratio of total water to dry food intake was, however, similar in both feeding regimens. 4. The fresh empty weight of the gut was increased by wet-feeding while its relative weight to body weight and the length of gut was not affected by dietary treatments. Significantly greater development of the tissue glands in the proventriculus and gizzard was observed in the birds given wet food; this was associated with the reduced thickness of the muscular layer of these segments. An increase in villus height was also observed in duodenum, small intestine, caeca and colon of birds given wet food, compared to those given dry food. CCPR was significantly (P<0.05) reduced by wet-feeding throughout the digestive tract. This was associated with a significant decrease in the mean viscosity of the gut contents and the concentration of volatile fatty acids (VFAs) in the caeca. 5. Wetting diets based on cereal grains caused a significant improvement in the performance of broiler chickens. The mechanism of the beneficial effects of wet feeding could be attributed to the decreased viscosity of gut contents; the greater development of the layer of villi in the digestive segments and the reduced CCPR in the crypts of the epithelium.     

Muscle protein turnover and tenderness in broiler chickens fed cimaterol

To investigate the impact of cimaterol (CIM) on muscle protein turnover, carcass and muscle composition, muscle cathepsin B + L activity and meat tenderness, 21-d-old broiler chickens (n = 88) were assigned to dietary treatments of either 0 or 1 ppm CIM. Fractional synthesis rates (FSR), fractional accretion rates (FAR), proximate composition and collagen content were determined in the breast muscle (BM); pectoralis major) and a group of leg muscles (LM; gastrocnemius and peroneous longus) from groups of six birds per treatment within each of two time periods (age = 38 or 56 d). Whole body composition, serum hydroxyproline content and BM cathepsin B + L activity also were measured. Fractional degradation rates (FDR) were calculated as the difference between FSR and FAR. Feeding CIM increased (P less than .01) whole body protein content. Weights of LM and percentage of body weight as BM and LM were increased (P less than .05) when CIM was included in the diet. Although FSR was not significantly reduced by CIM feeding it decreased (P less than .05) with increasing age. Due to decreases in FAR, FDR thereby was reduced by CIM 31.5% and 11.9% in BM and 38.2% and 37.4% in LM at 38 d and 56 d of age, respectively. Cathepsin B + L activities also were reduced 33.6% (P less than .01) and shear forces were increased by 41% (P less than .05) by CIM feeding. For chickens fed CIM, the correlation between cathepsin B + L activity and shear force was -.63 (P less than .01). Feeding CIM improved carcass leanness and muscling due to reductions in FDR and proteolytic enzyme activity. Feeding CIM also reduced meat tenderness.     

Passage rate through the anterior digestive tract of broiler chickens fed on diets with ground and whole wheat

1. Birds were fed diets containing ground or whole wheat and titanium dioxide for 10 min, followed by dissection of 4 birds per treatment after 30, 60, 90, 120, 150 and 180 min. 2. The crop, proventriculus and gizzard, duodenum, jejunum, and ileum from each bird were dried and combusted, and titanium content in each section was determined. 3. Significant amounts of titanium were found in the small intestine of the birds as soon as 30 min after being given feed containing titanium, and significant amounts had passed the small intestine after 120 to 150 min. 4. Titanium contents equivalent to approximately 5 g feed were eliminated from the gizzard per hour independently of whether ground or whole wheat was used. Thus, a hypothesis that the use of whole grain would slow down passage rate through the upper digestive tract was not supported by the current results.     

Inclusion body hepatitis in broiler chickens in Iraq

Eighteen outbreaks of inclusion body hepatitis (IBH) were identified in broiler chickens in Baghdad in 1977 and 1978. The disease was seen mainly in 4-to-6-week-old broiler chickens. The mortality rate did not exceed 1% in any outbreak investigated. The most common gross findings were stellate or punctiform hemorrhagic areas in markedly fatty livers. Noticed in many cases were enlarged and pale kidneys, hemorrhagic lesions in the skeletal muscles, and pale fattened bone marrow. Histological examination of tissues revealed fat droplets and intranuclear inclusion bodies in degenerated liver cells. Eosinophilic inclusion bodies were seen in all cases. Only five cases had basophilic inclusions along with the eosinophilic ones. The etiologic agent was isolated on chorioallantoic membrane (CAM) of 12-day-old embryonated chicken eggs. The disease was produced experimentally in 4-week-old chicks using infected CAM suspension.     

Linkage between the intestinal microbiota and residual feed intake in broiler chickens

Background: Intestinal microbiota plays a key role in nutrient digestion and utilization with a profound impact on feed efficiency of livestock animals. However, the intestinal microbes that are critically involved in feed efficiency remain elusive.Methods: To identify intestinal bacteria associated with residual feed intake(RFI) in chickens, male Cobb broiler chicks were individually housed from day 14 to day 35. Individual RFI values were calculated for 56 chickens.Luminal contents were collected from the ileum, cecum, and cloaca of each animal on day 35. Bacterial DNA was isolated and subjected to 16 S rRNA gene sequencing. Intestinal microbiota was classified to the feature level using Deblur and QIIME 2. High and low RFI groups were formed by selecting 15 and 17 chickens with the most extreme RFI values for subsequent LEfSe comparison of the difference in the microbiota. Spearman correlation analysis was further performed to identify correlations between the intestinal microbiota composition and RFI.Results: No significant difference in evenness, richness, and overall diversity of the microbiota in the ileum, cecum,or cloaca was observed between high and low RFI chickens. However, LEfSe analysis revealed a number of bacterial features being differentially enriched in either high or low RFI chickens. Spearman correlation analysis further identified many differentially enriched bacterial features to be significantly correlated with RFI(P 0.05). Importantly,not all short-chain fatty acid(SCFA) producers showed a positive association with RFI. While two novel members of Oscillibacter and Butyricicoccus were more abundant in low-RFI, high-efficiency chickens, several other SCFA producers such as Subdoligranulum variabile and two related Peptostreptococcaceae members were negatively associated with feed efficiency. Moreover, a few closely-related Lachnospiraceae family members showed a positive correlation with feed efficiency, while others of the same family displayed an opposite relationship.Conclusions: Our results highlight the complexity of the intestinal microbiota and a need to differentiate the bacteria to the species, subspecies, and even strain levels in order to reveal their true association with feed efficiency. Identification of RFI-associated bacteria provides important leads to manipulate the intestinal microbiota for improving production efficiency, profitability, and sustainability of poultry production.     

Effects of artemisinin in broiler chickens following chronic oral intake

Artemisinin has been used for centuries to treat malaria, intestinal tract helminthosis, diarrhea, and used as an antipyretic and sedative agent, but the usage in veterinary medicine is a new field. Recently, it has been used successfully to control experimental poultry coccidiosis. The present study aimed to determine the effects of different doses of artemisinin in broiler chickens with chronic usage. Sixty birds divided into one control and four treatment groups that fed rations mixed with artemisinin at doses of 17, 34, 68, and 136 ppm for 36 days. During the experiment, birds showed no clinical signs except anemia. In microscopic examinations, heart, lung, and spleen had no lesion, but liver, kidney, and brain showed various lesions. Degenerative lesions like intracytoplasmic eosinophilic inclusions were seen in both kidney and liver but fatty change was seen only in liver. There was no relationship between severity of the liver lesions and drug dosage. Central chromatolysis, scattered neuronal necrosis, and mild spongy changes were observed in five regions of the brain that were chosen for sectioning (motor cortex, cerebellar nuclei, midbrain nuclei, and hindbrain nuclei at two separate levels). Severity of lesions in brain was dose-dependent, and cerebral cortex was the most vulnerable area. Haematologic tests showed lower values for hematocrit and red blood cell count dose-dependently. In conclusion, artemisinin is a promising drug for prevention and control of coccidiosis in broiler chickens and its side effects are not too much serious especially at therapeutic doses.     

Silicon in broiler drinking water promotes bone development in broiler chickens

1. Skeletal abnormalities, bone deformities and fractures cause significant losses in broiler production during both rearing and processing. Silicon is an essential mineral for bone and connective tissue synthesis and for calcium absorption during the early stages of bone formation.

2. Performance was not affected by the addition of silicon. However, broilers receiving silicon showed a significant increase of phosphorus, zinc, copper, manganese and ash in the tibia.

3. In conclusion, broiler performance was not impaired by adding the tested silicon product to the drinking water. In addition, bone development improved, as demonstrated by higher mineral and ash content.

4. Further studies are required to determine the optimal concentration of silicon, including heat stress simulations, to better understand the effects of silicon on bone development.

     

Changes in feed consumption and water intake among broiler chickens subjected to melatonin treatment during the hot-dry season

Tropical Animal Health and Production - The experiment was conducted to evaluate changes in feed consumption and water intake among broiler chickens subjected to melatonin treatment during the...     

Dietary divercin modifies gastrointestinal microbiota and improves growth performance in broiler chickens

1. The aim of the present study was to investigate the effects of dietary administration of a divercin AS7 liquid preparation on broiler chicken performance, nutrient digestibility, counts of lactic acid bacteria (LAB) and coliform bacteria, as well as on the microbial activity in the gastrointestinal tract (GIT) as expressed by digesta pH and concentrations of short-chain fatty acids and lactic acid. 2. A total of 450 1-d-old male Ross 308 chickens were randomly distributed to three dietary treatments, with 15 pens per treatment and 10 birds per pen. The dietary treatments consisted of a positive control (PC) supplemented with 60 mg/kg salinomycin, a negative control (NC) without any additives, and the divercin (DIV) supplemented diet containing 0 x 2 mL/kg of the liquid divercin AS7 preparation. 3. The dietary divercin AS7 supplementation significantly increased body weight gain at 35 d compared to the NC group. Moreover, the pH of crop contents was higher and that of caecal contents lower in birds fed on the divercin supplemented diets. 4. Significantly lower counts of LAB were observed in the crops and caeca of the birds treated with divercin. Further, the divercin supplementation decreased lactic and succinic acid concentrations in the crop and ileum. 5. The present study demonstrates that the use of divercin supplemented diets can influence composition and activity of the microbiota in the broiler chicken GIT even in the lower parts that should otherwise not be targeted due to the peptide structure of the bacteriocin.     

Biochemical changes in layer and broiler chickens when fed on a high-glucosinolate rapeseed meal

Diets containing 500 g high-glucosinolate rapeseed meal/kg or an equivalent amount of soybean meal as the only protein supplement were fed to layer-type chickens and two broiler strains from 1 to 56 d of age. Additional groups of the former were maintained on the diets until they were 16 and 28 d old. The rapeseed meal produced thyroid hypertrophy in all strains but reduced the growth rate of only one of the broiler strains. The livers of chickens fed on rapeseed meal were enlarged and DNA analysis indicated hyperplasia, but no macroscopic lesions were found. The activities of aspartate transaminase, lactate dehydrogenase and alkaline phosphatase in the plasma were increased by rapeseed meal, suggesting liver damage. In all strains, feeding rapeseed meal increased plasma total protein, albumin and cholesterol and decreased urate. Hyperglycaemia accompanied by a decrease in plasma triglycerides occurred in the layer strain. Through its extra-thyroidal toxicity (-)5-vinyl-oxazolidine-2-thione (goitrin) was probably responsible for most of these changes.     

肉鸡血浆VLDL浓度的选择效应—肉仔鸡体重和血浆VLDL

以父线代肉种鸡为材料,用比浊法测定血浆ＶＬＤＬ浓度,分别以１６周龄,６周龄血浆ＶＬＤＬ浓度为选择指标建立零世代,一世代肉鸡高脂系和低脂系地肉鸡体重和血浆ＶＬＤＬ浓度的选择反应。结果：１．零世代,一世代肉鸡血浆ＶＬＤＬ浓度变异很大,变异系数分别为４３．６％－７４．６％和３８．７％－７９．９％,二个世代选择后,血浆ＶＬＤＬ浓度变异系数在高,低脂质中分别为３７％－５２％和３１％－４６％,表明对血浆ＶＬＤ