Dynamics of yolk sac resorption and post-hatching development of the gastrointestinal tract in chickens, ducks and geese

Under similar environmental conditions, 100 male Shaver-Starbro hybrid chickens, 100 male Mulard cross-line ducklings and 100 male Landaise goslings kept in 30 metabolic cages from the first day of life (10 birds of each species separately per cage) were chosen for the study. The animals were fed semi ad libitum diets with crude protein content and energy density similar to that used for poultry species, avoiding feed residues. During the first 21 days of life they received starter diets and from day 22 to 42 grower diets. Maize accounted for 23-40% and barley constituted 10-18%. Wheat accounted for 20.0% in starter diets and 10-18% in grower diets. Resorption of yolk sac residues, performance, development of the intestinal tract in young chickens, ducklings and goslings were assessed. During the first 5 days of life intensive absorption of yolk sac ingredients was observed. On day 7, residues of the yolk sac were found in more than 30% of chickens compared with approximately 10% in geese. In ducklings residues of the yolk sac were not found. On day 16 unabsorbed yolk sacs were found in approximately 10% of chickens. Liver and pancreas weighed the highest in geese and in ducks; in chickens the weight of these organs was significantly lower (p < 0.01). The relative values calculated to 100 g of metabolic body weight show that the average small intestine in chickens was significantly longer (p < 0.01) than in ducks or geese. The intestinal tract developed earlier in the chicken than in the water fowl.     

斑点肉鸭小肠液中消化酶活性变化探讨

以 0～45日龄斑点肉鸭为研究对象 ,测试 5 ,1 5 ,2 5 ,35 ,45日龄肉鸭小肠液中淀粉酶、脂肪酶、蛋白酶活性随年龄的变化趋势。结果表明 :淀粉酶、蛋白酶活性随日龄增大而升高 ,且 5～ 1 5日龄段显著升高 (P <0 0 5) ;脂肪酶活性在 5～ 1 5日龄段显著降低 ,1 5～ 45日龄段一直维持在较低水平。试验结果对斑点肉鸭饲料中营养的合理配比及外源性消化酶适时添加具有一定的指导作用     

The process of hatching in geese and ducks

The process of hatching in goose and duck From the 4th to the 16th or 17th day of incubation the wall of duck and goose amnion actively, peristaltically and rythmically contracts 20 and 12 times per minute, respectively. A pause of five seconds follows each 5th contraction. The contractions also passively influence the yolk sac, the allantois and the air cell. The M. complexus grows more than four times its original size during the 24th to the 27th day of incubation. It contains two kinds of myosin: neonatal myosin (200,000 Dalton) and adult myosin (480,000 Dalton). The amounts of the adult myosin present at the time of hatching is about 15 times the amount in the skeletal muscles. The process of hatching is described in the duck and goose.     

Digestibility and digestive organ development in indigenous and improved chickens and ducks fed diets with increasing inclusion levels of cassava leaf meal

Growing indigenous Cambodian chickens and ducks, and broiler chickens and White Pekin ducks were fed diets containing 0%, 7%, 14% and 20% of cassava leaf meal (CLM) to study the effects of CLM level on diet digestibility and gastrointestinal tract (GIT) and organ development. The coefficient of total tract apparent digestibility (CTTAD) of dry matter (DM) and intake of digestible DM decreased with increased dietary CLM. DM and digestible DM intake was higher for local breeds than for the corresponding exotic breeds, and higher for ducks than for chickens (p < 0.001), although there were no species or breed effects on CTTAD of DM (p > 0.05). Weight of small intestine, caeca, gizzard and pancreas, expressed as per kg body weight, increased with increased CLM in the diet (p < 0.001). There was no consistent diet effect on liver weight. Length of small intestine and caeca, expressed on a mass-specific basis, increased with dietary CLM content (p < 0.001). When expressed as per kg body weight small intestine, proventriculus, gizzard, pancreas and liver weights, and small intestine length, were higher in ducks than in chickens (p < 0.001), and were higher in the indigenous than in the improved breeds (p < 0.01), except for small intestine weights, which were similar. However chickens had higher weight of caeca (p < 0.001) and colon (p < 0.01) in absolute units and per kg body weight.     

禽流感病毒H5N1变异株灭活疫苗(Re-4株)对鸡、鸭和鹅的免疫效果研究

为系统评估禽流感病毒(AIV)H5N1变异株灭活疫苗(Re-4株)对家禽的免疫效果,本研究将Re-4株油乳剂灭活疫苗免疫SPF鸡和商品蛋鸡、商品鸭及商品鹅。免疫后每周采集血清测定HI抗体,绘制抗体消长曲线,免疫SPF鸡在免疫后2周、3周和50周时以105EID50剂量的强毒株(CK/SX/2/06)进行攻毒。研究结果显示,该疫苗对蛋鸡、鸭、鹅均具有良好的免疫效果,而且SPF免疫鸡血清HI抗体在4log2以上时能够完全抵抗CK/SX/2/06强毒的攻击。因此,根据实验结果推荐该油乳剂灭活疫苗的对上述禽类的免疫程序:商品蛋鸡10日龄颈部皮下注射0.3mL,60日龄和110日龄(开产前)时依次胸肌注射0.5mL和1.0mL进行免疫;商品鸭、鹅在2周龄均以0.5mL首免,5周龄和4月龄左右时以1mL的剂量肌肉注射方式进行加强免疫。     

谷氨酰胺对肉鸡肠道发育及小肠消化酶活性的影响

将180只1日龄AA肉仔鸡随机分成3组,设3个重复,每组60只,1组为对照组,2、3组为试验组,分别饲喂添加0%、0.2%、0.4%谷氨酰胺的基础日粮,试验期42 d,探讨了外源性谷氨酰胺对AA肉仔鸡小肠生长发育和消化道酶活性的影响.结果表明,在肉鸡饲料中添加外源性谷氨酰胺,能促进小肠的生长发育,显著增加肉鸡十二指肠、空肠和回肠重量、长度以及肠道指数(P＜0.05),提高小肠蛋白酶、脂肪酶、淀粉酶和胰蛋白酶活性(P＜0.05);谷氨酰胺的适宜添加剂量为0.2%.提示谷氨酰胺可作为肠道促生长添加剂在肉鸡饲料中使用,其适宜添加剂量为0.2%.     

Cytogenetic studies in domestic chickens and ducks

Typology and the number of chromosomes were studied in two species of domestic poultry: the domestic fowl (Gallus domesticus) and duck (Anas platyrhynchos domestica). The classical method, described by Konstantinov and Dobriyanov (1974), used in the trails, enabled typology only in the largest chromosomes. In the remaining microchromosomes the position of centromere was not determined. Microchromosomes appeared as points which were arranged by size in caryotypes. The domestic fowl had 78 chromosomes on the whole and the duck 80 chromosomes.     

The susceptibility of young chickens, ducks, and turkeys to the photosensitizing effect of Ammi visnaga seeds.

Young chickens, ducks, and turkeys were exposed to sunlight and fed various amounts of Ammi visnaga seeds for 14 days in an attempt to induce photosensitization. In chickens, seeds at 1.25% in the diet had no effect whereas 3% induced mild signs of photosensitization within 6 to 8 days. No visible effects resulted in ducklings from 1.5, 3 and 6% in the diet, or in turkey poults from 3%. These differences appear to be due to differences between these avian species in the metabolism of the photodynamic agent.     

Development of disaccharidase activity in the small intestine of broiler chickens

1. The changes in disaccharidase activity in the small intestine of broiler chickens were investigated in isolated enterocytes on d 18 of embryonic development and d 1, 7, 21, 35 and 56 after hatching. 2. The specific activities of maltase, lactase and trehalase were greatest on d 18 of embryonic development. After hatching, maltase specific activity gradually decreased until d 18. 3. After d 7 postnatally only traces of lactase and trehalase activity were found in the enterocytes. 4. Significant sucrase activity was found on d 18 of embryonic development and the activity of this enzyme increased 2-fold after hatch and remained generally constant up to d 35, after which the enzyme specific activity declined.     

Effect of dietary fibres on small intestine histomorphology and lipid metabolism in young broiler chickens

Two experiments were conducted to determine the influence of dietary fibres on small intestine histomorphology and lipid metabolism in broilers from 1 to 21 day of age. In experiment 1, diets containing insoluble [cellulose (CEL); 2% and 4%] or soluble [carboxymethyl cellulose (CMC); 2% and 4%] fibre were fed to broilers from day 1 to 21 post‐hatch and ileal tissue was collected at day 21 of age for histological evaluation. In experiment 2, broilers diet was supplemented with 0%, 1% or 2% insoluble fibre (Arbocel) during day 7 to 21 post‐hatch and plasma and liver lipid metabolism were evaluated at day 21. In experiment 1, inclusion of CMC reduced body weight gain (BWG) and feed intake (FI) and increased feed conversion ratio (FCR) compared with others. Intestinal histomorphology was unaffected by CEL, but CMC led to an increase in crypt depth (CD) and serosa thickness and a decrease in villus height (VH), villus width (VW), VH:CD ratio and villus surface area (VSA), rather than control and CEL groups. Treatment did not affect goblet cell type. Moreover, the CMC‐fed birds had greater total goblet cell count (GCC) as compared with others. In experiment 2, fibre inclusion was associated with increases in BWG from 7 to 14 day of age and an improvement in FCR, whereas FI was not influenced by treatments. Inclusion of fibre in the diet decreased the weight of the abdominal fat and cholesterol concentrations of liver and plasma. No significant effects on fatty acid composition of liver lipid were observed by fibre supplementation. These findings suggest dietary fibre affects performance, intestinal histomorphology and lipid metabolism in young chicks, which may directly affect poultry feeding strategies.     

Isolation and identification of Vibrio metschnicovii from domestic ducks and geese.

Seven Vibrio-like field strains of German origin were isolated culturally from diseased domesticated ducks, muscovy ducks and geese, and were compared with reference strains NCTC 8443 (type strain) and NCTC 11170 of Vibrio metschnicovii using classical phenotypic and chemotaxonomic tests. Some V. cholerae strains were included in the chemotaxonomic tests for comparative purposes. On the basis of the classical phenotypic characteristics studied and the numerical analysis of the whole-cell fatty acid patterns, the Vibrio-like field strains were identified as Vibrio metschnicovii. The identification tables and the database of the computer software of two commercial micro-identification kits (API-20 NE, ID-32 E) did not identify the field strains. Of the reference strains used, only NCTC 8443 was correctly identified by the ID-32 E software.     

Detection of florfenicol resistance genes in Riemerella anatipestifer isolated from ducks and geese

The cat gene, coding for chloramphenicol acetyltransferase has been reported for conferring the chloramphenicol resistance for Riemerella anatipestifer. Chloramphenicol acetyltransferases, however, are unable to inactivate florfenicol. In this study, 66 R. anatipestifer isolates were investigated for their susceptibility to chloramphenicol and florfenicol and the presence of floR gene. Results showed nine florfenicol intermediate or resistant R. anatipestifer isolates were all floR positive. The expression of floR gene in E. coli and inhibition studies with PAβN indicated that the floR gene was as an efflux pump conferring resistance to both chloramphenicol and florfenicol. Southern hybridization revealed the floR was located in the plasmid DNA of five isolates and in the chromosomal DNA of four isolates. Furthermore, two novel floR-carrying plasmids designated pRA0726 and pRA0846 were sequenced completely. pRA0726 was 11,704 bp in size with 10 putative open reading frames which included the floR, catB and bla(OXA-209) resistance genes. The most differences between sequences of pRA0846 and pRA0726 were the absence of a bla(OXA-209) gene and the deletion of 321 nucleotides of orf1 in pRA0846. Plasmid curing tests demonstrated that pRA0726 carried functional coding proteins for resistance to phenicol and β-lactam antimicrobials. To the best of our knowledge, this is the first report of presence of the floR and bla(OXA-209) resistance genes in R. anatipestifer.     

巨型艾美尔球虫感染对雏鸡肠道乳酸杆菌的影响

取200只红羽肉杂雏鸡,饲喂至8日龄,随机分为3个球虫卵囊剂量感染组(0.5×105、1.0×105和2.0×105个/羽),并设对照组;于感染后1、3、5、7 d,各组分别处死雏鸡5只,测定小肠中段乳酸杆菌的定植数量。结果表明:与对照组比较3个试验组雏鸡肠道的乳酸杆菌定植数量均有降低。其中试验Ⅰ组,在感染后1、3 d,肠道乳酸杆菌定植数对数值分别为(5.46±0.14)和(5.57±0.14),与对照组比差异不显著(P>0.05);感染5、7 d后,分别为(5.71±0.45)和(5.80±0.52),达到差异显著水平(P<0.05)。试验Ⅱ、Ⅲ组,在感染后1 d,达到差异显著水平(P<0.05)。感染后3、5、7 d,肠道乳酸杆菌定植数量对数值与对照组比较达到极显著水平(P<0.01)。试验证明大剂量球虫感染可明显降低雏鸡小肠段乳酸杆菌的定植数量。     

Comparative albumin determinations in ducks, chickens, and turkeys by electrophoretic and dye-binding methods

Serum total protein, albumin, and globulin concentrations in male ducks, turkeys, and chickens were compared, using electrophoretic and dye-binding methods, as well as using a bovine and chicken albumin standard. When a chicken standard was used for determination of albumin and globulin concentrations by automated methods, results were more comparable with results of electrophoresis than were those when a bovine standard was used.     

Serological survey and risk factors for Toxoplasma gondii in domestic ducks and geese in Lower Saxony, Germany

To obtain estimates for the prevalence of Toxoplasma gondii infection in ducks and geese in Germany, enzyme-linked immunosorbent assays (ELISA) were established based on affinity-purified T. gondii tachyzoite surface antigen 1 (TgSAG1) and used to examine duck and goose sera for T. gondii-specific antibodies. The results of 186 sera from 60 non-infected ducks (Anas platyrhynchos) and 101 sera from 36 non-infected geese (Anser anser) as well as 72 sera from 11 ducks and 89 sera from 12 geese inoculated experimentally with T. gondii tachyzoites (intravenously) or oocysts (orally) and positive in a T. gondii immunofluorescent antibody test (IFAT) were used to select a cut-off value for the TgSAG1-ELISA. Sera obtained by serial bleeding of experimentally inoculated ducks and geese were tested to analyze the time course of anti-TgSAG1 antibodies after inoculation and to assess the sensitivity of the assays in comparison with IFAT. In ducks, IFAT titres and ELISA indices peaked 2 and 5 weeks p.i with tachyzoites, respectively. Only three of six geese inoculated with tachyzoites at the same time as the ducks elicited a low and non-permanent antibody response as detected by the IFAT. In the TgSAG1-ELISA, only a slight increase of the ELISA indices was observed in four of six tachyzoite-inoculated geese. By contrast, inoculation of ducks and geese with oocysts led to an increase in anti-TgSAG1 antibodies within 1 or 2 weeks, which were still detectable at the end of the observation period, i.e. 11 weeks p.i. Inoculation of three ducks and three geese with oocysts of Hammondia hammondi, a protozoon closely related to T. gondii, resulted in a transient seroconversion in ducks and geese as measured by IFAT or TgSAG1-ELISA. Using the newly established TgSAG1-ELISA, sera from naturally exposed ducks and geese sampled in the course of a monitoring program for avian influenza were examined for antibodies to T. gondii; 145/2534 (5.7%) of the ducks and 94/373 (25.2%) of the geese had antibodies against TgSAG1. Seropositive animals were detected on 20 of 61 duck and in 11 of 13 goose farms; the seroprevalences within positive submissions of single farms ranged from 2.2% to 78.6%. Farms keeping ducks or geese exclusively indoors had a significantly lower risk (odds ratio 0.05, 95% confidence interval 0.01-0.3) of harboring serologically positive animals as compared with farms where the animals had access to an enclosure outside the barn.     

多粘菌素对雏鸭血液中SOD活性及丙二醛含量的影响

以口服及肌注方式给雏鸭喂服或注射不同剂量多粘菌素B，测定了血浆中SOD活性和MDA的含量。结果表明，雏鸭给予多粘菌素后，口服组及肌注低剂量组雏鸭于给药后2d血浆SOD活性明显升高，血浆中MDA含量于给药后4d显著或极显著升高，肌注中，高剂量组雏鸭血浆SOD活性于给药后2d显著降低，而MDA含量于给药后2d显著或极显著升高，随后给药各组雏鸭SOD活性均极显著下降。