Intercalated duct cells in the chicken pancreatic islet with special reference to the alloxan administration.

The intercalated duct cells were observed in the A and B islets of the chicken pancreas. These cells adhered with each other by intercellular junctional complexes at the apical side. They had many microvilli projecting into the lumen. Abluminally, they displayed extended slender cytoplasmic processes between islet endocrine cells. Administration of alloxan resulted to denser cytoplasm and a more prominent thickening of cytoplasmic processes of the intercalated duct cells, although the blood glucose levels did not show appreciable changes by the treatment. The intercalated duct epithelial cells appeared clearly as stellate cells. The lysosomes increased in size and number with passage of time after alloxan administration. The present findings may suggest that intercalated ducts are not only anatomically important as a structure passing through the islet but also play physiologically by protecting the islet endocrine cells.     

An investigation of the relationship between duct system and A cell-rich and PP cell-rich pancreatic islets in the canine pancreas.

The pancreata of four six-month-old dogs of the same mother, two with both the pancreatic and accessory pancreatic ducts (X-type) and two with only the accessory pancreatic duct (Y-type), were examined in this study. To clarify the relationships between the type of pancreatic duct system and the composition of pancreatic endocrine cells, the pancreata were examined immunohistochemically using antiserum against four types of pancreatic hormones (glucagon, insulin, somatostatin and pancreatic polypeptide). In all areas of the X- and Y-type duct system pancreata, B cells accounted for 52-82% of the total number of islet cells, and D cells accounted for 4-15%. In the X-type ducts system, the percentages of A and PP cells in the right and left lobes of the pancreas differed greatly. It was found that A and PP cells appear in inverse proportion to each other and that there exist A cell-rich and PP cell-rich pancreatic islets. The A cell-rich pancreatic islets appeared in the left lobes along the accessory pancreatic duct, while the PP cell-rich pancreatic islets were observed in the right lobes along the pancreatic duct. The body of the pancreas contained both A cell-rich and PP cell-rich pancreatic islets. In the Y-type duct systems, A cell-rich pancreatic islets appeared in the right lobes. These findings indicate that the composition of A and PP cells in pancreatic islets is closely related to the type of duct system.     

鸡的病理表现与常见病的关系

在检测条件不具备的情况下，兽医工作者在禽病门诊工作中主要运用解剖学方法，通过观察鸡的病理变化，对疾病进行诊断并确诊，以作为治疗的依据。笔者从事禽病门诊工作多年，现将在禽病门诊实践中的体会作简要介绍，仅供广大禽病门诊兽医工作者和饲养者参考。１皮肤、肌肉、胸腺１．１皮肤①皮下气肿：主要由气囊破裂溢气引起，粗暴抓鸡或碰伤所致。②皮下水肿：多见于饲料酸败中毒或VE和硒缺乏症、痢特灵中毒症（有用药史）、食盐中毒症（有超量用盐史）、皮下水肿型大肠杆菌病。③皮下脓肿：主要是绿脓杆菌病。脚垫肿常见于大肠杆菌病。…     

The relationship between physical activity and leg health in the broiler chicken

1.?The relationship between the physical activity and leg health of broiler chickens was assessed on a semi-commercial scale.

2.?Three batches of birds (2128 per batch) were raised under two lighting regimes during the photoperiod; either a step-wise change of light intensity alternating between an illuminance of 200 and 10 lx or a constant illuminance of 10 lx. The activity of focal individuals (24 per batch) was observed at 2, 4 and 6 weeks of age, and leg health assessed weekly, based on gait score, the prevalence of burns on the hock and foot pad, and angulation and rotation of the leg at the intertarsal joint. Cortical bone density and thickness and area moments of inertia of the mid-physis tibiotarsus were measured post mortem at 6 weeks of age.

3.?The step-wise change in light intensity did not affect overall performance, activity or leg health.

4.?An individual bird's activity did not affect its gait score, the prevalence of hock burn or foot pad burn, cortical density or thickness or shape of the tibiotarsus. Sex of the bird was the only factor to affect significantly the area moment of inertia in the horizontal and vertical planes of the tibiotarsus, with females showing a lower moment of inertia for both. No variable had a significant effect on cortical density or thickness. Mean cortical density was low across all birds and may indicate that, when allowed to move freely as much or as little as they choose, broiler chickens do not exercise enough or do not perform the higher impact activities required to affect bone quality.

5.?These findings imply that the activity of broiler chickens raised on a semi-commercial scale is unaffected by step-wise changes in light intensity and that other husbandry measures are needed to raise activity and hence improve leg health.     

Anatomical relationship between enkephalin-containing neurones and caecum-projecting neurones in the chicken intestinal nerve

The anatomical relationship between enkephalin-immunoreactive neurones and caecum-projecting neurones in the intestinal nerve of Remak (INR) of the chicken was investigated using retrograde transport of cholera toxin subunit B and immunohistochemistry with anti-enkephalin serum. After injection of cholera toxin into the base or body of the caecum, labelled neurones were mainly observed in the cranial part of the rectal INR. Enkephalin-immunoreactive neuronal cell bodies were found in the caudal part of the rectal INR and their fibres closely surrounded caecum-projecting neurones in the cranial part of the rectal INR. Diameters of caecum-projecting neurones surrounded with enkephalin-containing terminals were significantly larger than those of caecum- projecting neurones without enkephalin-terminals (P < 0.01). From these results, it is suggested that enkephalin-containing neurones are able to affect large-sized caecum-projecting neurones. This pathway may be involved with unique motility of the rectum and caeca that uric acid is retrogradely carried from the cloaca to the caeca.     

微卫星标记与鸡蛋品质性状关系的研究

本试验分别对60周龄文昌鸡和新扬州鸡进行了蛋品质的测定,测定了8个性状为:蛋重、蛋壳重、蛋壳厚度、蛋壳强度、哈氏单位、蛋形指数、蛋黄重、蛋黄颜色。通过统计软件,对各蛋品质性状进行了相关分析,并通过选用20对微卫星标记,筛选出了与哈氏单位、蛋重有关的分子遗传标记。结果表明:与60周龄新扬州鸡的哈氏单位有关的标记为2号染色体上MCW239和4号染色体上的ADL260,与60周龄新扬州鸡的蛋重有关的标记为2号染色体上的ADL176和MCW239,与60周龄新扬州鸡蛋壳强度有关的标记Z染色体上的LEI229;而与60周龄文昌鸡哈氏单位相关的有2号染色体的的ADL176、MCW239和4号染色体的MCW240,与60周龄文昌鸡蛋重相关的是4号染色体上的标记LEI119,与60周龄蛋壳强度相关的标记为Z染色体上的MCW246和LEI229。     

Pancreatic function following partial pancreatectomy and anastomosis of the pancreatic duct to the stomach or duodenum in dogs.

The effects of pancreatic duct anastomosis to stomach (stomach group) or duodenum (duodenal group) on pancreatic function were examined in dogs following two thirds pancreatectomy. Normal fasting blood glucose concentrations were maintained in both groups despite significant reductions in glucose tolerance in the stomach group, and reductions in fasting insulin and insulin peak response in both groups. Pancreatic exocrine function was significantly decreased in both groups, though plasma p-aminobenzoic acid (PABA) concentrations were generally higher in the duodenal group. A correlation was found between plasma trypsin-like immunoreactivity (TLI) and pancreatic weight. These results indicate that anastomosis of the pancreas to bowel can be undertaken with minimal postoperative complications and that the site of the anastomosis influences pancreatic function. They suggest that preservation of more than one third of the pancreas is required for optimal function. The complementary information provided by the PABA and TLI tests suggests their dual application will be clinically useful for the detection and characterisation of naturally occurring pancreatic diseases.     

Differences between the anticoccidial potencies of monensin in maize-based or wheat-based chicken diets

Experiments were carried out to investigate why the anticoccidial ionophore monensin is more potent against the coccidiumEimeria tenella in chickens fed on a maize-based diet (as in the USA) than in chickens fed on a wheat-based diet (as in the UK). The explanation seems to be that the pathogenicity ofE. tenella is lower in maize-fed chickens than in wheat-fed chickens, whether monensin is present in the diet or not. Possible reasons for this are suggested. The better survival of maize-fed birds may be partly due to protective effects of the higher concentrations of vitamins A and E derived from their diet. Furthermore, the higher concentrations of niacin and riboflavin in wheat than in maize may enhance coccidial pathogenicity. These opposing factors might combine to cause equivalent infection levels to produce more severe coccidiosis in chickens fed on a wheat-based diet than on a maize-based diet.     

免疫鸡群感染新城疫强毒后排毒及其HI抗体消长

给两组二次新城疫(ND)疫苗免疫的鸡群分别于40日龄、60日龄经胸肌注射强毒株F48E8(剂量为0．25mL),观察排毒和其HI抗体效价。结果表明：鸡在感染强毒后第2天开始排毒,在第3～6天和第11～14天出现两次排毒高峰,整个排毒过程可达3周,其中抗体水平较低者排毒时间相对较长,频率较高;强毒感染初期,个体HI抗体先下降1～3个滴度,然后上升,且感染前低者上升速度较快,幅度亦较大。     

高原地区矮小鸡与藏鸡屠宰试验

通过对在高原地区10只成年矮小鸡和10只成年藏鸡屠宰测定,分析结果显示:平均体重矮小鸡比藏鸡高2．2％;藏鸡公鸡全净膛率为53．9％,矮小鸡公鸡全净膛率为64．9％,差异极显著;藏鸡母鸡全净膛率为58．1％,矮小鸡母鸡全净膛率为51．5％,差异极显著;藏鸡公鸡半净膛率为74．2％,矮小鸡公鸡半净膛率为81．5％,差异显著;藏鸡母鸡半净膛率为77．1％,矮小鸡母鸡半净膛率为66．2％,差异极显著。经测定说明矮小鸡的屠宰率高于藏鸡。     

鸡大肠杆菌抗体效价与攻毒保护率的平行关系试验研究

用与制造菌苗株一致的培养物制备检测抗原,检测30日龄雏鸡免疫后抗体效价,对不同抗体滴度的雏鸡进行了攻毒保护性试验.结果表明,抗体效价在3log2以下不具备保护力;抗体效价为4log2攻毒保护率≥60%;抗体效价为5log2时,保护率在80%以上;抗体效价在7log2时,保护率可达100%.     

Infection of the chicken with a virulent or avirulent strain of Mycoplasma gallisepticum alone and together with Newcastle disease virus or E. coli or both

The influence of the virulence of M. gallisepticum (Mg) was studied in multiple infections of chickens involving Mg, Newcastle disease virus (NDV) and E. coli. Separate groups of 3-week-old chickens were inoculated supra-conjuctivally with a virulent and an avirulent strain of Mg alone and in combination with the La Sota strain of NDV, the 01 serotype of E. coli, and both NDV and E. coli. In addition, chickens were inoculated with NDV alone, E. coli alone, and with NDV and E. coli; one group was left uninfected.Clinical signs, lesions, recovery of the pathogens and the serological response were observed for all groups for 3 weeks after infection and for those involving Mg alone and Mg together with NDV for 18 weeks.No clinical signs were seen in any of the birds; in each infected group some showed mild lesions of the trachea and air sacs without any marked difference among the groups.Although the numbers of birds examined were small, the virulent strain of Mg was more readily recovered than the avirulent, from the respiratory tract, in the first 3 weeks following multiple infections. However, the virulence of Mg had no influence on the recovery of the other pathogens.For the first 6 weeks after infection there was a direct relationship between the virulence of the Mg and the proportion of birds with agglutinins to the Mg rapid serum agglutination (RSA) test in single or multiple infections; multiple infections enhanced the antibody response to both virulent and avirulent mycoplasma. For NDV, multiple infections, particularly involving E. coli, enhanced the peak titre of haemagglutination-inhibition antibodies and accelerated their appearance; the virulence of the Mg had no apparent effect on this.Neither the mycoplasma nor NDV were detected in the trachea by immunofluorescence.     

Influence of substrate and/or neurohormonal mimic on in vitro pancreatic enzyme release from calves postruminally infused with partially hydrolyzed starch and/or casein

Our objectives were to determine the effects of neuroendocrine challenge and substrates on in vitro alpha-amylase and trypsin release in pancreatic tissue collected from Holstein calves (n = 24; 88 +/- 3 kg) abomasally infused for 10 d with tap water (control), partially hydrolyzed starch (SH; 4 g/[kg of BW x d]) and/ or casein (0.6 g/[kg of BW x d]). The caudal portion of the pancreas was removed, rinsed with ice-cold saline, cut into approximately 2 x 2-mm segments, and incubated in oxygenated Krebs Ringer bicarbonate buffer containing no substrate (control), glucose, amino acids, or VFA at 39 degrees C. After 60 min of incubation, neurohormonal mimics (none; control), carbachol (acetylcholine analog; 10 microM final), or caerulein (cholecystokinin mimic; 100 nM final) were added to the flasks and tissue was incubated for 60 min. Pancreatic tissue concentrations and in vitro release of alpha-amylase and trypsin decreased (P < 0.001) in calves abomasally infused with SH. Carbachol increased (P < 0.10) alpha-amylase and trypsin release in tissue collected from all calves. An effect of caerulein to increase alpha-amylase release (P < 0.10) was only observed with prior exposure to abomasal casein infusion in vivo or with simultaneous incubation with amino acids in vitro. Caerulein increased (P < 0.10) trypsin release in tissue collected from all calves except for those receiving SH + casein. Glucose decreased (P < 0.10) alpha-amylase release from pancreatic tissue collected from calves receiving abomasal control and casein treatments. Amino acids decreased (P < 0.10) alpha-amylase and trypsin release from pancreatic tissue collected from calves receiving the abomasal control treatment. Glucose, amino acids, and VFA decreased (P < 0.10) trypsin release from tissue collected from calves receiving abomasal SH. These data indicate that carbachol can stimulate pancreatic enzyme release in vitro. Caerulein, however, is only effective in stimulating in vitro pancreatic enzyme release in tissue from calves with an increased postruminal protein supply or in tissue incubated with amino acids. The results indicate that postruminal and local nutrients might be important in altering the responsiveness to a neuroendocrine challenge and could be an important regulatory event involved with dietary adaptation in ruminants.     

The relationship between serum biotin and oxidant/antioxidant activities in bovine lameness

Serum biotin concentrations, erythrocyte superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), reduced glutathione (GSH) and plasma thiobarbituric acid reactive substances (TBARS) were measured in 36 dairy cows, 18 of them were healthy and served as control. In the 18 cows with lameness problems, there were 5 cows with interdigital necrobacillosis, 5 cows with subsolar abscessation, 2 cows with solar ulcers, 2 cows with white line disease, 2 cows with chronic laminitis and 2 cows with septic arthritis. The degree of lameness was estimated to be slight in 3 cows, moderate in 11 cows and severe in 4 cows. Plasma fibrinogen levels and TBARS concentrations were increased significantly (P≤0.05) in lame cows compared to control group. The antioxidant enzymes GSH-Px, and CAT concentrations were increased significantly (P≤0.05) in lame cows. The level of reduced glutathione and the activity of SOD were significantly decreased in affected cows compared to healthy ones. Serum biotin levels in healthy cows ranged from 2.25 to 3.5ng/ml while in lame cows, biotin levels ranged from 1.17 to 2.3ng/ml. Biotin levels correlated positively with blood GSH (r=0.870, P≤0.05), (r=0.735, P≤0.05) and with GSH-Px (r=0.539, P≤0.05), (r=0.637, P≤0.05) and with SOD (r=0.637, P≤0.05), (r=0.449, P≤0.05) and with catalase (r=0.533, P≤0.05), (r=0.585, P≤0.05) in both healthy and lameness affected subjects, respectively.     

A relationship between gait and breakdown in the horse

A biomechanical model of running has been presented. A basic premise has been that the swing time is nearly independent of speed. In fact, both the racehorse and the trotter have nearly equal swing times. Consequently, as speed increases and the stance phase becomes shorter, the horse must compensate by increasing his extension or the length of the airborne phase (or both). The safe speed which allows the horse adequate preparation time for contact of a leg with the ground is calculated, using a stride-by-stride analysis of the motion of the horse. This is seen to be a very sensitive function of the overlap time in the gait. The overlap between the legs appears to affect both the ultimate performance potential of the horse and also his prospects for soundness.     

营养素与免疫关系的研究进展

营养素与免疫机能之间存在密不可分的联系。充分合理的营养供应可使动物免疫机能得到最大限度的发挥，从而预防某些疾病的发生。作者综述了近年来的一些研究成果，在分子水平上阐述了营养素与免疫体系的作用关系。某些重要营养素(例如：铁)虽然被广泛研究，但其转运机制还不是很清楚，所以对其免疫机能的研究不能深入开展。尽管这样，对营养素与免疫机能关系的研究，还是为动物饲养提供了大量的科学依据。     

The effects of parenteral iron dextran and/or desferrioxamine on the development of experimental pseudotuberculosis in the domestic chicken (Gallus domesticus)

Abstract The development of disease following oral challenge with Yersinia pseudotuberculosis (serotype 11) was compared in four groups of five birds treated with a parenteral dose of 10 mg iron dextran (Imferon), 10 mg of iron dextran plus 10 mg of the chelating agent desferrioxamine (Desferal), 10 mg of desferrioxamine or 10 mg of dextran 2 days before the experiment. Four groups of two birds received the above treatment regimens but no bacterial challenge. In iron dextran treated birds, oral challenge resulted in faecal shedding for the 10 day duration of the experiment, whereas in those birds which received dextran or desferrioxamine alone, the duration of faecal shedding was significantly less. Serological titres to the lipopolysaccharide antigen of the challenge bacteria were also lower in the groups not pretreated with iron dextran. The birds pretreated with iron dextran had diarrhoea and were clinically unwell 2 days following the initial oral challenge. Birds not given iron dextran showed no clinical signs of disease. Histological examination of five selected areas in the liver, spleen and intestine of each bird indicated that birds in the groups treated with iron dextran prior to bacterial challenge had significantly more intestinal lesions than birds in the groups not treated with iron. In contrast, there were significantly more lesions in the spleens of birds not pretreated with iron dextran. There was no evidence of stainable iron in the livers of birds challenged with Y pseudotuberculosis 10 days after an injection of 10 mg of iron dextran. This is in contrast to birds given iron dextran and no bacteria. It was concluded that pretreatment of birds with iron dextran resulted in more severe clinical disease, prolonged faecal shedding with associated intestinal lesions and higher serological titres to bacterial antigen. The number of lesions in the spleen and liver was not necessarily correlated with the severity of clinical disease, and in all infected birds the hepatic iron levels were significantly lower than in the non-infected control birds 10 days after oral challenge. It seems probable that the chicken has a high requirement for iron during infection with Y pseudotuberculosis and mobilises stored and exogenously supplied iron for tissue repair and immunological function.     

The effects of parenteral iron dextran and/or desferrioxamine on the development of experimental pseudotuberculosis in the domestic chicken (Gallus domesticus)

The development of disease following oral challenge with Yersinia pseudotuberculosis (serotype 11) was compared in four groups of five birds treated with a parenteral dose of 10 mg iron dextran (Imferon), 10 mg of iron dextran plus 10 mg of the chelating agent desferrioxamine (Desferal), 10 mg of desferrioxamine or 10 mg of dextran 2 days before the experiment. Four groups of two birds received the above treatment regimens but no bacterial challenge. In iron dextran treated birds, oral challenge resulted in faecal shedding for the 10 day duration of the experiment, whereas in those birds which received dextran or desferrioxamine alone, the duration of faecal shedding was significantly less. Serological titres to the lipopolysaccharide antigen of the challenge bacteria were also lower in the groups not pretreated with iron dextran. The birds pretreated with iron dextran had diarrhoea and were clinically unwell 2 days following the initial oral challenge. Birds not given iron dextran showed no clinical signs of disease. Histological examination of five selected areas in the liver, spleen and intestine of each bird indicated that birds in the groups treated with iron dextran prior to bacterial challenge had significantly more intestinal lesions than birds in the groups not treated with iron. In contrast, there were significantly more lesions in the spleens of birds not pretreated with iron dextran. There was no evidence of stainable iron in the livers of birds challenged with Y pseudotuberculosis 10 days after an injection of 10 mg of iron dextran. This is in contrast to birds given iron dextran and no bacteria. It was concluded that pretreatment of birds with iron dextran resulted in more severe clinical disease, prolonged faecal shedding with associated intestinal lesions and higher serological titres to bacterial antigen. The number of lesions in the spleen and liver was not necessarily correlated with the severity of clinical disease, and in all infected birds the hepatic iron levels were significantly lower than in the non-infected control birds 10 days after oral challenge. It seems probable that the chicken has a high requirement for iron during infection with Y pseudotuberculosis and mobilises stored and exogenously supplied iron for tissue repair and immunological function.