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Intraepithelial lymphocytes in the excurrent ducts of the testis of the domestic fowl (Gallus domesticus).

Cells considered to be lymphocytes are reported in the epithelial lining of the excurrent ducts of the testis of normal and vasoligated domestic fowl. They resemble those already reported in the rat and monkey epididymal epithelium, the human intestinal mucosa, and in the bursa of Fabricius. The cytoplasm is usually less dense than that of adjacent epithelial cells, and contains only a few organelles. The nucleus is highly heterochromatic and with no definite nucleolus. Cytoplasmic processes are found to extend from the cell in between epithelial cells. The possible role of these cells in the reproductive tract of the cockerel is discussed.

Animals↗

Calcium adenosine triphosphatase and secretion of koilin membrane in the gizzard of the fowl.

The localization of calcium adenosine triphosphatase (Ca(2+)-ATPase) was determined histo- and ultracytochemically in the gizzard gland cells of the adult domestic fowl. Surface and chief gland cells exhibited faint and inconstant basolateral activity in contrast to basal cells, whose basolateral cell membrane constantly showed deposition on the external side. Intracellular enzyme activity was localized on the luminal aspect of Golgi membranes in all types of gland cells. Lysosomes also reacted positive for Ca(2+)-ATPase. Neither membranes of secretory vesicles nor cortical cytoplasm of the secretory pole exhibited enzyme activity. From these results it is speculated that calcium is not essentially involved in the secretion of the koilin membrane in terms of storage of the secretory material, transport to the secretory surface and release into the lumen. Ca(2+)-ATPase activity rather seems to be related to differentiation and maturation processes and to intracellular storage of Ca2+.

Animals↗

Grouping of fowl adenoviruses based upon the restriction patterns of DNA generated by BamHI and HindIII.

Based upon the restriction patterns of DNAs generated by restriction endonucleases BamHI and HindIII, 17 fowl adenovirus strains representing 11 serotypes were placed into 5 groups: group A, strains CELO and 112; group B, strains 340 and TR-22; group C, strains KR-5 and C-2B; group D, strains 380, 685, SR-48, SR-49, and A-2; and group E, strains YR-36, CR-119, X-11, H-6, TR-59, and 764.

Adenoviridae↗

Serological relationships within the group E fowl adenoviruses.

Antisera were raised in chickens to six group E fowl adenoviruses (FAV) which have been divided into a highly virulent (hypervirulent) and a mildly virulent subgroup using restriction endonuclease analysis. Virus neutralisations showed that these two distinct restriction endonuclease groups were distinguishable serologically, and indicated a possible vaccine candidate for use against the hypervirulent FAV. The suitability of this candidate was established in challenge experiments where vaccination with this virus protected against challenge from another hypervirulent virus as well as one of the mildly virulent FAV.

Adenoviridae Infections↗

Passive cutaneous anaphylaxis in the domestic fowl.

Passive cutaneous anaphylaxis (PCA) has been demonstrated in young and adult domestic fowl using antisera obtained from actively sensitized chickens on the day of their maximal susceptibility to systemic anaphylaxis. Young chickens are more sensitive to histamine and PCA reaction than adults. The PCA reaction was inhibited by the H1-histamine receptor blocker, mepyramine. In the PCA reaction of 2 h sensitization period, the main exudating cells were heterophils, mononuclear cells (lymphocytes, monocytes and macrophages) and some basophils. This study suggests a possible role for circulating basophils in the mediation of early acute inflammatory reaction of immunological origin.

Aging↗

Evolutionary relationships of Red Jungle Fowl and chicken breeds.

Published results were reassessed and original data are provided regarding the origin and relatedness of four postulated chicken breed lineages, egg-type, game, meat-type and Bantam, to each other and to the basic ancestral species of jungle fowls, Gallus gallus. A system approach was employed concerning the planning of the experiments. One element of the system approach is the choice of the breeds to be compared with G. gallus. These breeds were supposed to represent major evolutionary branches of chickens. Four experiments on genetic relationships were conducted using different estimation criteria including morphological discrete characters, body measurements, biochemical markers, and the activity of serum esterase-1. The greatest similarity was found between G. gallus and the egg-type breeds of Mediterranean roots and/or true Bantams. This fact might testify that the indicated chicken groups occupied earlier stages in the evolution from the wild progenitor to the present biodiversity of chickens in the world.

Animals↗

Oral infection with the Salmonella enterica serovar Gallinarum 9R attenuated live vaccine as a model to characterise immunity to fowl typhoid in the chicken.

BACKGROUND: Salmonella enterica serovar Gallinarum (S. Gallinarum) is the causative agent of fowl typhoid, a severe systemic disease of chickens that results in high mortality amongst infected flocks. Due to its virulence, the immune response to S. Gallinarum is poorly characterised. In this study we have utilised infection by the live attenuated S. Gallinarum 9R vaccine strain in inbred chickens to characterise humoral, cellular and cytokine responses to systemic salmonellosis. RESULTS: Infection with 9R results in a mild systemic infection. Bacterial clearance at three weeks post infection coincides with increases in circulating anti-Salmonella antibodies, increased T cell proliferation to Salmonella challenge and increased expression of interferon gamma. These responses peak at four weeks post infection, then decline. Only modest increases of expression of the pro-inflammatory cytokine interleukin-1beta were detected early in the infection. CONCLUSION: Infection of chickens with the 9R vaccine strain induces a mild form of systemic salmonellosis. This induces both cellular and humoral immune responses, which peak soon after bacterial clearance. Unlike enteric-associated Salmonella infections the immune response is not prolonged, reflecting the absence of persistence of Salmonella in the gastrointestinal tract. The findings here indicate that the use of the S. Gallinarum 9R vaccine strain is an effective model to study immunity to systemic salmonellosis in the chicken and may be employed in further studies to determine which components of the immune response are needed for protection.

Journal Article↗

Effects of dietary fat on virus-induced pancreatic carcinogenesis in guinea fowl.

The present study was performed to assess the effects of diets supplemented with low (5%) and high (20%) corn oil on a Pts 56 retrovirus-induced model of pancreatic carcinogenesis in guinea fowl. The early microscopic lesions appear after 3 mo after virus treatment and progress over time. Eight to 10 mo after initiation, up to 100% of virus-inoculated birds develop multiple hyperplastic and neoplastic pancreatic lesions of duct/ductular phenotype. Short-term (1-4 mo) feeding of low- or high-fat diets, beginning at Month 3, had no significant effects on body and pancreatic weight. However, the incidence, multiplicity, and areas of the pancreatic tissue occupied by intra- and interlobular aggregates of hyperplastic ducts with mucinous metaplasia of the lining cells were significantly increased compared with the birds fed the common diet. At the same time, development of ductular neoplasms, particularly carcinomas, was retarded compared with the common diet-fed controls. Long-term (5-7 mo) fat intake resulted in an increase in body weight gain, while absolute pancreatic weights remained relatively constant. Furthermore, the high- and low-fat diets caused a significant increase in areas of retrovirus-induced pancreatic lesions, as well as an increase in multiplicity of ductular neoplasms compared with short-term fat feeding. It is concluded that short-term feeding of diets supplemented with 5% or 20% corn oil delayed the development of the common virus-induced ductular neoplasms, particularly carcinomas, and had an enhancing effect on development of hyperplastic inter- and intralobular aggregates of ducts. This finding was not observed, however, during the long-term feeding period of the study.

Animals↗

Adrenocortical cell function in the hypophysectomized domestic fowl: effects of growth hormone and 3,5,3'-triiodothyronine replacement.

The control of adrenocortical function in the domestic fowl (Gallus domesticus) was investigated using adrenocortical cells isolated from hypophysectomized (hypox) and intact cockerels and from hypox cockerels injected with T3, purified chicken GH (cGH), and T3 plus cGH. Corticosterone in plasma and cell incubations was measured by RIA. Cellular responses to varying concentrations of steroidogenic agents were fitted and statistically analyzed by computer. Hypophysectomy reduced the basal plasma corticosterone (B) concentration to 53% of the value in intact birds and eliminated a stress response. Although hypophysectomy reduced adrenal weight by 20%, it did not change relative adrenal weight (milligrams per 100 g BW). However, replacement with cGH increased relative adrenal weight by 24%, whereas replacement with T3 or T3 plus cGH reduced relative adrenal weight by 16%. In the absence of steroidogenic agents, there were no detectable differences in B production by adrenocortical cells isolated from various experimental groups. However, with a maximal steroidogenic concentration of ACTH, B production by isolated adrenocortical cells from hypox birds was 61% of that by cells from intact birds. The ED50 of ACTH for cells from hypox cockerels was 2.7 times greater than that of cells from intact cockerels, thus indicating a loss of cell sensitivity to ACTH after hypophysectomy (the greater the ED50, the lesser the cell sensitivity). Although cGH replacement increased maximal B production (Bmax) induced by ACTH to 329% that by cells from hypox cockerels, it increased the ACTH ED50 3.6 times, thus decreasing cell sensitivity more than hypophysectomy alone. In contrast to cGH, T3 replacement maintained the cell sensitivity to ACTH at the level of cells from intact birds, but lowered Bmax to 54% that of cells from hypox cockerels. The combination of cGH and T3 administered to hypox cockerels both maintained cell sensitivity to ACTH and raised the Bmax to 358% that of cells from hypox animals. These treatments also affected 8-bromo-cAMP-induced Bmax and pregnenolone-supported Bmax, but did not significantly alter the ED50 of these agents.(ABSTRACT TRUNCATED AT 400 WORDS)

8-Bromo Cyclic Adenosine Monophosphate↗

Protein malnutrition in the domestic fowl induces alterations in adrenocortical function.

Adrenocortical function was investigated in immature, dietary protein-restricted domestic fowl (Gallus gallus domesticus). White Leghorn cockerels (2 weeks old) were fed isocaloric semipurified diets containing either 8% [low (L)] or 20% [normal (N)] soy protein for 4 weeks ad libitum. Cockerels were quickly killed by decapitation and exsanguination. Trunk plasma corticosterone (B) and ACTH levels were measured by RIA. Maximal B-binding capacity (CBC) of plasma was also measured. In addition, in randomly selected cockerels, a rough index of the B clearance rate was determined. Finally, to determine the influence of protein malnutrition on adrenocortical cell function per se, we measured the acute (2-h) B responses of highly enriched adrenocortical cell populations to various ACTH analogs, 8-bromo-cAMP (8-Br-cAMP), and cellular B production maximally supported with 25-hydroxycholesterol. Plasma B and ACTH concentrations of L cockerels were, respectively, 160% greater and 32% less than those of N cockerels. In addition, plasma B clearance rate of L birds was 85% greater than that of N birds, thus suggesting a greater B secretion rate in L birds. However, maximal plasma CBC of L cockerels was 59% less than that of N cockerels. Thus, the free plasma B concentration of L birds was greater than that of N birds. The increase in the plasma B concentration of L cockerels is explained in part by the relative adrenal weight of these birds which was 88% greater than that of N cockerels. In addition, there were differences at the adrenocortical cell level. On an equal cell concentration basis, basal and maximal B production values (stimulated by ACTH analogs and 8-Br-cAMP, and supported by 25-hydroxycholesterol) of L cockerel adrenocortical cells were, respectively, 73% and 139% greater than those of N cockerel adrenocortical cells. In addition, maximal ACTH-induced aldosterone production of L bird cells was 104% greater than that of N bird cells, such that the ratio of aldosterone production to B production was not altered by protein deprivation. The data suggest that the greater steroidogenic capacity of L cockerel cells was due to an increase in intracellular steroidogenic enzyme content and/or activity and not to an alteration in the composition of adrenocortical cell types within the populations of isolated cells. Furthermore, ACTH analog ED50 values for B, aldosterone, and cAMP production by L bird cells were about one third to one fifth the values for N bird cells, thus indicating that L bird cells were about 3-5 times more sensitive to ACTH than were N bird cells.(ABSTRACT TRUNCATED AT 400 WORDS)

8-Bromo Cyclic Adenosine Monophosphate↗

Muscle force-length dynamics during level versus incline locomotion: a comparison of in vivo performance of two guinea fowl ankle extensors.

For a terrestrial animal to move in the complex natural environment, the limb muscles must modulate force and work performance to meet changing mechanical requirements; however, it is not clear whether this is accomplished via a collective shift in function by all limb muscles, or a division of labor among limb muscles. Do muscles differ in their ability to modulate force-length contractile function to meet the mechanical demands of different locomotor tasks? We explore this question by examining the in vivo force-length performance of the guinea fowl Numida meleagris lateral gastrocnemius (LG) and digital flexor-IV (DF-IV), during level and incline locomotion. During level locomotion, the LG and DF-IV exhibit differing muscle fascicle strain patterns: the LG shortens by 10-15% while developing force, whereas the DF-IV undergoes a stretch-shorten cycle with large strain amplitudes and small net strains of 1-8%. Furthermore, the DF-IV operates at higher muscle stresses (92-130 kPa, compared to 23-39 kPa for LG) and possesses a longer tendon, which allows the DF-IV tendon to recover greater elastic energy than the LG tendon. During incline locomotion, these muscles contribute only one-third of the energy expected for their mass, with the DF-IV exhibiting high stride-to-stride variability in work output. While the stretch-shorten cycle of the DF-IV muscle may allow more economic force production, it also leads to large changes in work output with small changes in the relative timing of force and strain. Thus, while the primary determinants of LG work are net strain and mean force, the primary determinant of DF-IV work is the phase relationship between force and strain. Our results suggest that, in addition to influencing a muscle's mechanical performance during steady level locomotion, morphology also affects its capacity and mechanism for altering work output for different locomotor tasks.

Analysis of Variance↗

The cost of running uphill: linking organismal and muscle energy use in guinea fowl (Numida meleagris).

Uphill running requires more energy than level running at the same speed, largely due to the additional mechanical work of elevating the body weight. We explored the distribution of energy use among the leg muscles of guinea fowl running on the level and uphill using both organismal energy expenditure (oxygen consumption) and muscle blood flow measurements. We tested each bird under four conditions: (1) rest, (2) a moderate-speed level run at 1.5 m s(-1), (3) an incline run at 1.5 m s(-1) with a 15% gradient and (4) a fast level run at a speed eliciting the same metabolic rate as did running at a 15% gradient at 1.5 m s(-1) (2.28-2.39 m s(-1)). The organismal energy expenditure increased by 30% between the moderate-speed level run and both the fast level run and the incline run, and was matched by a proportional increase in total blood flow to the leg muscles. We found that blood flow increased significantly to nearly all the leg muscles between the moderate-speed level run and the incline run. However, the increase in flow was distributed unevenly across the leg muscles, with just three muscles being responsible for over 50% of the total increase in blood flow during uphill running. Three muscles showed significant increases in blood flow with increased incline but not with an increase in speed. Increasing the volume of active muscle may explain why in a previous study a higher maximal rate of oxygen consumption was measured during uphill running. The majority of the increase in energy expenditure between level and incline running was used in stance-phase muscles. Proximal stance-phase extensor muscles with parallel fibers and short tendons, which have been considered particularly well suited for doing positive work on the center of mass, increased their mass-specific energy use during uphill running significantly more than pinnate stance-phase muscles. This finding provides some evidence for a division of labor among muscles used for mechanical work production based on their muscle-tendon architecture. Nevertheless, 33% of the total increase in energy use (40% of the increase in stance-phase energy use) during uphill running was provided by pinnate stance-phase muscles. Swing-phase muscles also increase their energy expenditure during uphill running, although to a lesser extent than that required by running faster on the level. These results suggest that neither muscle-tendon nor musculoskeletal architecture appear to greatly restrict the ability of muscles to do work during locomotor tasks such as uphill running, and that the added energy cost of running uphill is not solely due to lifting the body center of mass.

Animals↗

Comparison of running energetics in male and female domestic fowl.

Carbon dioxide production (VCO2) and end-exercise venous lactate concentration were compared in intensively-trained, mature male and female domestic fowl running on a treadmill for 10-min periods at maximal and sub-maximal work loads. The relationship between VCO2 and running speed was linear and had the same slope in male and female birds. However the maximum sustainable running speed of the males was approximately twice that in the females and the maximum weight-specific VCO2 was 60% higher in males. End-exercise venous lactate concentration rose significantly above resting at work loads above 75% maximum in females, but only at work loads above 95% maximum in fully-trained males. The results indicate a greater work capability in male than in female birds in the conditions of the experiments.

Animals↗

Respiration in exercising fowl. I. Oxygen consumption, respiratory rate and respired gases.

1. Oxygen consumption, respiratory frequency, and the PO2 of expiratory and interclavicular air sac gases were continuously monitored in six female domestic fowl trained to exercise on a treadmill for 10 min periods at normal or elevated air temperatures. 2. At normal temperatures (20 +/- 2 degrees C) the cost of locomotion rose from 0.46 ml O2 kg-1 m-1 at 0-3 km h-1 to 0.77 ml O2 kg-1 m-1 at the maximum speed of 4.3 km h-1. At 32 +/- 2 degrees C, Vo2 increased by as much as 20% compared to normal temperatures. 3. Hyperventilation occurred at all speeds and at both normal and elevated temperatures. End-tidal and interclavicular PO2 increased, in a parallel manner with speed, the latter remaining consistently 6-7 Torr less than the former both at rest and during exercise.

Animals↗

Respiration in exercising fowl. II. Respiratory water loss and heat balance.

1. Respiratory water loss and rectal temperature were measured in domestic fowl running for 10 min on a treadmill at speeds of 1.24-4.3 km h-1 in air temperatures of 20 +/- 2 degrees C or 32 +/- 2 degrees C. 2. At given speeds the water loss at 32 +/- 2 degrees C was approximately twice that at 20 +/- 2 degrees C and the end-exercise rectal temperature was 0.5-0.8 degrees C higher. 3. At 20 +/- 2 degrees C, respiratory evaporation accounted for 10-12% of the total metabolic energy used at all speeds. At 32 +/- 2 degrees C, the fractional respiratory heat loss fell from 26.5% at 1.24 km h-1 to 17% at 3.6 km h-1. The fraction of the total metabolic energy stored as body heat rose progressively with air temperature.

Animals↗

The respiratory responses of the fowl to hot climates.

Respiratory rate (f) and tidal volume (VT) have been measured at normal and at warm ambient temperatures (Ta) in adult domestic fowl by means of a whole body plethysmograph. Resting values of f = 23 +/- 9 min-1 and of VT = 25.6 +/- 0.9 ml min-1 were found. At Ta 30, 35 or 40 degrees C f increased in direct relation to the severity of the heat stress reaching a maximum values of 273 +/- 12 min-1; VT fell uniformly in all three climates to a minimum of 9.0 +/- 0.5 ml. Total ventilation (V) showed a linear relation with f during first-phase panting. Second-phase panting occurred only at Ta 40 degrees C; V increased at first but subsequently fell as the decline in f became more pronounced.

Acclimatization↗

Influence of dopamine, levodopa and apomorphine on maximal electroconvulsive seizure in the domestic fowl (Gallus domesticus).

The influence of dopamine, levodopa and apomorphine on maximal electroconvulsive seizure was studied in young chicks, adult cocks and rats. The susceptibility of chicks to maximal electroshock seizure increased with age between 1 to 7 days. Low to moderate doses of dopamine (12.5-150 mg/kg, i.p.), levodopa (6.25-25 mg/kg, s.c.) and apomorphine (0.25-2.0 mg/kg, s.c.) significantly (P less than 0.005) protected chicks against electroshock seizure, while high doses (200-400 mg/kg, i.p. of dopamine, 50-200 mg/kg, s.c. of levodopa and 2.5-5 mg/kg, s.c. of apomorphine) enhanced electroshock seizure in 1 to 7 day old chicks. However, when 14 day old chicks were used, these dopaminoceptor agonists protected the chicks against maximal electroshock seizure. Noradrenaline (1-40 mg/kg, i.p.) had no significant effect on electroshock seizure in chicks. Both pimozide (4 mg/kg, i.p.) and haloperidol (0.4 mg/kg, i.p.) antagonized the effects of levodopa (12.5 and 50.0 mg/kg, i.p.) and apomorphine (0.5-5 mg/kg, s.c.) on maximal electroshock seizure. The seizure susceptibility of both adult rats and fowls to electroshock was not altered by dopamine (12.5-400 mg/kg, i.p.). Central dopamine neurotransmission might be involved in the biphasic dose-dependent effects of dopamine, levodopa and apomorphine on maximal electroshock seizure in young chicks.

Age Factors↗