Cardioelectric Field on the Bird Body Surface during Activation of Atrial Myocardium

Cardioelectric field (CEF) on the body surface of birds (hen and pigeon) at the period of atrial excitation was studied by the method of the 64-channel synchronous electrocardiotopography. At the period of the atrial depolarization in the birds the zone of CEF negative potentials on the body surface is located cranially with respect to the zone of positive potentials. At the initial moments of P wave the minimum is located in the cranial (hen) or middle (pigeon) third of the dorsal body surface, while the maximum—in the area of the heart projection onto the ventral (hen) or left-lateral (pigeon) body surface. The maximum and minimum of the potential reach the greatest value at the period of the middle part of the P wave (near the peak), their amplitude being higher in pigeons. The distribution dynamics of the CEF potentials on the body surface is similar in different bird species and is characterized by stability in mutual disposition of positive and negative zones. The interspecies and intraspecies CEF variability on the body surface at the period of the atrial activation seems to be due to differences in the heart disposition in the chest. At the period of the atrial myocardium activation, CEF on the bird body surface reflects adequately projection of the potential distribution on epicardium and the sequence of spreading of excitation in the atrial myocardium, including that in the presence of several fronts of depolarization waves.     

鸡垂体前叶提取物诱导鸡超数排卵

Chicken anterior pituitary extract(CAPE) and acetone dried chicken anterior pituitary (ACAPE) were injected intraperitoneally into normal laying hens (‘ovulation suppressed’ following pretreatment with daily subcutaneous injection of PMSG) to induce multiple ovulations. The dose of PMSG, the effect of CAPE and ACAPE and the time required for induction of ovulation following injection of ovulation inducing hormone were determined. The results revealed that (1) when 75 IU PMSG was administered daily, egg laying stopped in 33% of the treated hens within 6 days after the first injection. However, the percentage of hens showing the same effects changed significantly (over 95%) within 3 to 6 days when the amount of PMSG was increased to 100 IU; (2) the number of ovulated ova was 1 00±0 00, 2 33±0 26,2 20±0 20 respectively after receiving 100 mg, 200 mg and 300 mg; the number of ovulated ova was 2 00±0 00, 2 86±0 48, 3 00±1 50 respectively after receiving 10 mg, 15 mg and 20 mg ACAPE; (3) The time from injection to ovulation in almost all hens was about 7 5 h except one hen ovulated about 6 5 h after receiving ACAPE .     

Formation of alanine and glutamine in chick (Gallus domesticus) skeletal muscle

1. Incubation of extensor digitorum communis muscles from fed chicks in the presence of plasma concentrations of branched-chain amino acids (BCAA) increased the formation of glutamate, glutamine and alanine. This effect was inhibited by 1.5 mM L-cycloserine. 2. 2-Oxoisocaproate (0.1 and 0.5 mM) increased the formation of leucine but decreased that of glutamate, glutamine and alanine. 3. NH4Cl (0.3 mM) increased the formation of glutamine, and decreased the release and intracellular concentrations of glutamate and alanine. 4. Our results demonstrate that alanine and glutamine are synthesized de novo in chick skeletal muscle and demonstrate the similarity in alanine and glutamine synthesis in skeletal muscle between the domestic fowl and mammals.     

Histochemical studies on the developing adrenal gland of Gallus domesticus

Summary The distribution of adrenaline, noradrenaline, aliesterases and non-specific cholinesterases in the cortical and medullary cells and that of ascorbic acid in the cortex have been studied histochemically in sections of adrenal glands from embryonic, juvenile and adult chicken. Both the catecholamines are secreted by the embryonic medulla from the 11th day of incubation but noradrenaline is the more abundant of the two hormones at all stages and it is secreted by the majority of chromaffin cells. There is a tendency for the adrenaline-secreting cells to predominate in the subcapsular layer of the medulla. Both types of chromaffin cells reveal considerable cholinesterase activity consistently from the second half of incubation period onwards.A high concentration of aliesterases and ascorbic acid are developed and maintained in the cortical cords from the time the cortex begins secretory activity, namely, the 10-day incubation stage. Lower concentrations of cholinesterases are also present in the cells of the cortex. The cords of the peripheral zone of cortex show higher concentrations of both the enzymes and ascorbic acid than those of the central zone.From a thesis submitted to McGill University, Montreal, Canada in 1963 in partial fulfillment of the requirements for the degree of Doctor of Philosophy. The work was done during tenure of a Canadian Commonwealth Scholarship.     

Connections of the IMHV in the domestic chick Gallus domesticus

The responses to single electrical stimuli have been recorded from neurons in the brains of domestic chicks, by using an in vitro preparation consisting of a coronal slice taken from the forebrain. All slices were cut so that they contained the intermediate part of the medial hyperstriatum ventrale (IMHV). When such a slice is bathed in standard Krebs' solution there is no evidence that the excitation produced by a single stimulus can be transmitted more than 1 mm either towards or away from the IMHV. The addition of bicuculline methiodide (more than 3 x 10(-6) M) to Krebs' solution allows the excitation produced by a single stimulus to spread in all directions throughout the dorsal half of a coronal slice. At points remote (more than 1.5 mm) from the stimulated point, the magnitude of the spreading wave of excitation bears an all-or-nothing relation to the strength of stimulus used to excite it. This wave of excitation spreads from the excited point in all directions without attenuation at 0.9 +/- 0.017 (s.d.) m s-1 and consists of a prolonged burst of activity of the invaded neurons. The properties of coronal slices described above are also true of brain slices cut in a parasagittal plane. The spreading response to a single stimulus given in the presence of bicuculline, can be reduced in magnitude by the addition of AP-5 but it still spreads throughout the dorsal part of the slice at the same velocity. The response can be eliminated by the addition of kynurenic acid. The addition of curare to the bathing medium produces similar responses that spread in a similar fashion to those seen under bicuculline. These results suggest that the dorsal part of the forebrain of the domestic chick (in fact, the part derived from the embryological alar plate) contains a network of reciprocally connected local circuits. Transmission throughout the network is normally prevented by active inhibition.     

Body weight, semen quality, and age at sperm production of hemicastrated and intact cockerels (Gallus domesticus)

Spermatozoa were found earlier in the ejaculates of hemicastrated cockerels and the mean body weight of the hemicastrates was significantly (P less than 0.01) greater than that of the intact cockerels. The mean values for sperm concentration/ml, and total spermatozoa in the ejaculates of the hemicastrates were significantly greater (P less than 0.01) than those of the intact cockerels. Differences existed between the hemicastrates bearing the left testis, and those bearing the right testis in respect of age at sperm production, sperm/concentration and total spermatozoa in the ejaculate.     

Specific arrangement of chromosomes in the spermiogenesis of Gallus domesticus

On the chromosomes of the rooster the constitutive heterochromatin (C-bands) is to be found for the most part at the centromeres. The position of the centric heterochromatin in spermatids and sperm is not randomly distributed. In early, round spermatids one heterochromatic block lies at this exact position on the membrane that develops into the tip of the sperm nucleus (acrosomal chromocenter). During the elongation of the spermatid nucleus another heterochromatic block comes to lie on the basal nuclear membrane. The other centromeres arrange themselves tandem-wise between the acrosomal and the basal chromocenters. Comparisons have been made between this specific arrangement and the location of chromosomes in the sperm of amphibians and mammalians.     

Re-establishment of the stress response in Gallus domesticus after hatching

Cold caused a hypercorticosteronaemia and hypothermia in the 2-day-old chick. Heat did not affect plasma corticosterone concentrations, despite the birds becoming hyperthermic. The 2-day-old chick has a lower resting concentration of corticosterone than the 1-day-old. The minimum effective dose of corticotrophin in stimulating a hypercorticosteronaemia was 0.5 IU/kg in the former, 1.0 IU/kg in the latter. It is concluded that stress non-responsiveness persists for about 48 hr after hatching and that it is due to a temporary inhibition of hypothalamic function.     

成人心肌致密化不全的研究进展

成人心肌致密化不全（NVM）是一种特殊少见的心肌病,是由于胚胎发育早期正常心内膜发育停滞所致的心脏病,特征是心内膜面有粗大的肌小梁和交错的深隐窝。临床表现为充力性心力衰竭、心律失常和系统性血栓栓塞等。目前以对症支持治疗为主,预后较差。现介绍其发病机制、病理解剖学、临床特点、诊断及诊断标准、治疗等方面进展,为临床诊断及治疗提供客观依据。近年来医师对该疾病认识的不断提高,使其误诊率和漏诊率有所下降,同时使患者的预后和生活质量得到明显改善,但还存在许多争议,需要进一步探讨。     

Recombination nodules in the oocytes of the chicken, Gallus domesticus

Chicken oocytes at pachytene were processed with the microspreading technique (Moses, 1977), and their synaptonemal complex (SC) complements were analyzed by electron microscopy. Ellipsoidal nodules, 140 X 120 nm in diameter, were associated with the central space of synaptonemal complexes. The average number of nodules per pachytene oocyte was 57.5. The number of nodules per bivalent showed a clear linear relationship with SC length, except for the microchromosomes, which showed a single obligatory nodule. The distribution of nodules along the 10 longest SCs was nonrandom, with low frequencies in the vicinity of kinetochores and high frequencies near the telomeres. The microchromosomes showed a single nodule whose average location was 1.21 micron from the kinetochore. In the ZW pair there was a single nodule whose average location was 0.31 micron from the paired telomeres and not more than 0.65 micron from them. The total number of nodules per cell and the number of nodules in each of the five major bivalents showed good agreement with the total number of chiasmata and the number of chiasmata of the major bivalents of roosters. Thus, these nodules share the characteristics of recombination nodules described in other organisms. The single, obligatory, strictly localized recombination nodule found in the pairing end of the ZW pair strongly suggests that recombination between the Z and W chromosomes in the female chicken is a regular process that may be similar to the obligatory recombination between the pairing ends of the human X and Y chromosomes that was recently described in studies using DNA probes.     

Activation of dynein adenosine triphosphatase and flagellar motility of demembranated spermatozoa by monovalent salts at 40 degrees C in the domestic fowl, Gallus domesticus

1. At 40 degrees C, around the normal avian body temperature, demembranated fowl spermatozoa with no addition of monovalent chlorides were immotile. 2. Demembranated spermatozoa become motile at 40 degrees C when 0.1-0.5 M concentrations of NH4Cl, NaCl and KCl were added to the reactivation medium, with maximum motility occurring at 0.2-0.3 M in all cases. 3. The addition of NH4Cl, NaCl and KCl also stimulated the ATPase activity of crude dynein extract. In contrast, LiCl did not appreciably affect motility and ATPase activity. 4. These results showed that the flagellar dynein ATPase activity of fowl spermatozoa could be stimulated by the addition of certain monovalent chlorides, except LiCl, and demembranated spermatozoa might be motile at 40 degrees C.     

Development of otoconia in the embryonic chick (Gallus domesticus)

In the chick (Gallus domesticus) embryo, otoconium formation started first over the macula sacculi around the 4th day of incubation, and a day later over the macula utriculi. It was determined that each otoconium formed as a result of the segmentation of the immature otolithic membrane, and that the calcium responsible for otoconium calcification was incorporated into the organic matrix of each otoconium in the form of small electron-dense granules (20-150 nm in diameter). The presence of calcium in these granules was confirmed by histochemical staining with osmic-potassium pyroantimonate, by EDTA chelation, and by X-ray microanalysis under the electron microscope.     

Surface morphology of basilar papilla of the tufted duck Aythya fuligula,and domestic chicken Gallus gallus domesticus

Quantitative details of the surface morphology of the hearing organ, the Papilla basilaris, as seen in the scanning electron microscope are described for the tufted duck Aythya fuligula and for comparison for the domestic chicken Gallus gallus domesticus, for which some published information is already available. As in the other avian species investigated to date, each papilla shows a unique constellation of features. The papilla of the tufted duck is 3.5 mm long in the unfixed state and contains 8,200 sensory hair cells. It shows systematic changes in its surface features along the length and across the width of the sensory epithelium. In general, its features and those of the chicken Papilla basilaris can be described as relatively primitive in comparison with other species. The tufted duck papilla does, however, show one feature that has so far been found to be well developed only in advanced papillae; the number of stereovilli per hair cell bundle is generally much higher on hair cells of the neural than those on the abneural side. This difference is only weakly developed in the chicken. It is clear that features considered to be evolutionarily advanced were acquired independently of one another during evolution and that each bird species can show a mosaic of primitive and advanced features. © 1996 Wiley-Liss, Inc.