Effect of methimazole-induced hypothyroidism on adrenal and gonadal functions in male Japanese quail (Coturnix japonica)

To investigate the effect of hypothyroidism on gonadal and adrenal functions in male Japanese quail (Coturnix japonica), hypothyroidism was induced in male adult Japanese quail by daily administration of 2-Mercapto-1-methylimidazole (methimazole) in their drinking water. Four weeks after methimazole treatment, the Japanese quail were sacrificed, and the plasma concentrations of free triiodothyronine (FT3), free thyroxine (FT4), total T3 (TT3), total T4 (TT4), corticosterone, testosterone, LH and immunoreactive (ir) inhibins were measured by radioimmunoassay, the testes and adrenal glands were removed and weighed and the thyroid glands and testes were fixed in 4% paraformaldehyde for histological observation. The results showed that the hypothyroidism induced by methimazole caused a significant decrease in body and testes weight; the plasma levels of FT3, FT4 and TT4 significantly decreased, and the hypothyroid quail possessed a greater number of small follicles and more follicular epithelial cells in the thyroid gland. In addition, hypothyroidism resulted in a significant decrease in the plasma concentrations of corticosterone, LH, testosterone and ir-inhibin. Furthermore, no spermatogenesis was found in the seminiferous tubules of the methimazole treatment groups. These results clearly demonstrate that hypothyroidism caused both gonadal and adrenal disturbances in the adult male Japanese quail.     

精氨酸对雄性动物繁殖性能的影响

L-精氨酸是氮氧化物(NO)和多胺等生物活性物质合成的前体,具有改善繁殖能力、心血管功能、胃肠道发育及调控免疫功能等多种作用。本文就精氨酸对雄性繁殖能力的影响进行了论述,以期对雄性动物的养殖生产有一定的理论作用。     

Effect of dietary fumonisin B1 on laying Japanese quail

1. A 28-d experiment was conducted to evaluate the effects of fumonisin B1 (FB1) on egg production and egg quality of young laying Japanese quail fed on fumonisin-contaminated rations. 2. To this end, 128 7-week-old birds were randomly distributed into 4 experimental groups (32 birds per group) and given rations containing 0 (control), 10, 50 and 250mg FB1/kg feed. Each treatment consisted of 4 replicates of 8 quail. Egg production and egg weight were checked daily. Feed consumption and feed conversion were determined weekly. Eggs laid on the last day of each 7-d period were collected and subjected to individual analysis for specific gravity, Haugh units and percentage eggshell. 3. Compared with controls, quail given > or = 50 mg FB1/kg had reduced feed intake and lower body weight gain. Feed conversion was reduced only in birds given 250 mg FB1/kg. 4. Mean egg production and egg weight were lower in birds given 250mg FB1/kg. Eggshell weight was reduced in birds given > or =50mg FB1/kg. However, mean specific gravity, Haugh units and percentage eggshell were not affected by FB1. 5. No histopathological changes were observed in liver, kidney or heart samples from any treatment group. 6. The results indicated that exposure to FB1 at concentrations > or = 50 mg/kg could adversely affect quail performance, emphasising the importance of controlling fumonisin contamination of quail rations.     

Effect of rate of stimulation on hatching time in Japanese quail

A series of Japanese quail clutches was incubated, then one egg from each clutch was stimulated at a rate between 1 click/10 sec. and 1000 clicks/sec. The hatching time of the stimulated egg was recorded and compared with that of its siblings. Embryos stimulated by discrete clicks at rates of 1 1/2–60/sec. were speeded up; while those stimulated between rates of 100–500 clicks/sec. were slowed down. These results are considered as contributing towards a possible explanation of the synchronisation of hatching in this species.     

Effects of oestrogen and anti-oestrogen on the cells of the endosteal surface of male Japanese quail

1. The endosteal cellular response occurring in the early stages of medullary bone formation was histologically examined in the femurs of male Japanese quail treated with oestrogen and antioestrogen. 2. The numbers of endosteal cells decreased, and preosteoblasts and osteoblasts increased, on the endosteal surface following oestrogen treatment. 3. After oestrogen and anti-oestrogen treatment the numbers of preosteoblasts and osteoblasts on the endosteal surface did not increase. However, endosteal cells slowly decreased in number and osteoclasts increased. 4. This study demonstrates that differentiation of osteoblasts is induced by oestrogen stimulation and suggests that osteoclasts occur by oestrogen inhibition on the endosteal surface.     

Effects of supplemental vitamin E in diet of Japanese quail on male reproduction, fertility and hatchability

1. Two experiments were conducted to examine the effect of feeding higher supplemental vitamin E (VE) concentrations on male reproductive variables, fertility and hatchability of quails. 2. In experiment 1, sixty 5-week-old male quails, reared in individual cages, were fed male breeder diets supplemented with 0, 75, 150, 225 or 300 IU alpha-tocopherol acetate/kg. At 10 weeks, observations on cloacal gland size, foam production, testes weight and blood samples for testosterone estimation were taken. 3. In experiment 2, 50 male and 50 female cage-reared quails (5 weeks old) were fed male breeder and layer rations, respectively, supplemented with 0, 75, 150, 225 or 300 IU/kg. At 13 weeks, 9 different mating pairs (5 pairs/group) were formed. Group 1 contained one control male and one control female in each of 5 pens. In groups 2 to 5, control males were paired with females on supplements of 75, 150, 225 or 300 IU/kg. In groups 6 to 9, control females were paired with males on supplements of 75, 150, 225 and 300 IU/kg. During subsequent adaptation and egg collection periods, each of 10 d, control layer ration was fed to all groups. All the eggs laid during the 10-d egg collection period were incubated artificially to estimate fertility and hatchability. The trial was repeated at 15 weeks. 4. Adult male quails receiving moderate supplemental VE (75 and 150 IU/kg) had a higher cloacal gland index, quantity of foam secretion, testicular weight and plasma testosterone than quails fed on either VE-deficient or more highly supplemented diets (225 and 300 IU alpha-tocopherol acetate/kg). 5. It was concluded that a supplement of 75 IU VE/kg in maize/soybean diet could provide the best reproductive performance of male breeder quails. Cloacal gland index, quantity of foam secretion, testicular weight and plasma testosterone can serve as indirect indicators of testicular activity and fertilising ability in quails. Supplemental VE did not affect the fertility and hatchability of male and female Japanese quails.     

Effect of dietary cereal on liver and plasma lipids in laying Japanese quail

1. In three experiments the effect of diets containing maize or wheat on hepatic and plasma lipids in laying japanese quail were studied. In two of these diets of equal energy, nitrogen and fat contents were used. 2. Liver weight, relative to body weight, liver lipid content and plasma lipid concentration were greater in birds fed on maize-containing diets. 3. The maize-containing diet also produced more (14 : 0, 16 : 0, 16 : 1 and 18 : 1) and less (18 : 0, 18 : 2 and 20 :4) fatty acids in the liver lipid. 4. Egg production was not affected by the treatments. 5. The effect of dietary cereal on hepatic and plasma lipids may be due to altered lipogenesis and the quail may be a useful model for the laying hen with respect to hepatic lipid accumulation.     

牛磺酸对不同月龄雄性大鼠生殖器官指数及生殖激素水平的影响

通过给不同月龄雄性W istar大鼠饮用添加1%牛磺酸或1%β-丙氨酸(牛磺酸转运抑制剂)的自来水,研究牛磺酸对不同月龄雄性大鼠体重、生殖器官指数及生殖激素分泌水平的影响。结果表明:牛磺酸对不同月龄大鼠体重、睾丸指数、前列腺指数没有明显的影响,但显著提高了14月龄大鼠的精囊腺指数;显著提高不同月龄雄性大鼠的血清睾酮水平(P<0.05),对血清促卵泡生成素(FSH)、促黄体生成素(LH)水平没有显著的影响。     

Effect of restraint upon hypothalamic and adrenal catecholamines in Japanese quail

1. Changes in catecholamine concentration after periods of restraint up to 48 h in male Japanese quail have been measured. 2. Hypothalamic catecholamines decreased after 10 min restraint. Dopamine concentration increased after 4 h and persisted to 48 h. 3. Plasma catecholamines increased after 10 min, remained high for 2 h and then decreased despite continuing restraint. Catecholamine content of adrenals slightly decreased during restraint. 4. The activity of adrenal phenylethanolamine-N-methyl transferase increased from the 4th hour of restraint.     

Ontogeny of copulatory behaviour in male Japanese quail classified by their T-maze performance as hatchlings

1. This study examines the time courses of male mating behaviours using quail that were categorised at 2 d of age as high performance (HP) or low performance (LP) individuals in a T-maze. 2. Individually caged males from each T-maze category were observed for 5 min after a female of the same category (HP or LP) was introduced into their home cages as a sexual partner at 4, 5, 6, 8, 10 and 12 weeks of age. The number of grabs, mounts and cloacal contacts performed by each male and his copulatory efficiency (number of cloacal contacts/number of grabs; CE) were determined at each time interval. 3. No differences were observed in the proportion of HP and LP males performing grabs at any of the ages evaluated. However, a greater proportion of HP males showed mounting and cloacal contact behaviour, coupled with a higher CE than did their LP counterparts at 5 and 6, 6 and 8, and 8 weeks of age, respectively. At those ages, a higher mean number of mounts and cloacal contacts were also observed. No significant sexual behaviour differences between HP and LP quail were observed at 10 and 12 weeks of age. 4. The results suggest that rapid negotiation of the T-maze in hatchlings is associated with accelerated puberty in male quail. The differential reproductive behaviour of HP males during the development of puberty does not remain extant in fully developed quail. 5. The finding of accelerated male developmental sexual activity responses in HP quail indicates that selection for T-maze HP behaviour may allow males to be successfully bred at an earlier age.     

Effect of acute stress on Catecholamine content in the hypothalamic nuclei of Japanese quail

1. Concentration of noradrenaline, adrenaline and dopamine in eight hypothalamic nuclei or areas (nucleus hypothalamicus medialis anterior, n. periventricularis magnocellularis, n. hypothalamicus lateralis anterior, n. hypothalamicus medialis posterior, n. hypothalamicus lateralis posterior, eminentia medialis, n. tuberis, area hypothalamica posterior) have been determined by a sensitive radioenzymatic micromethod in male Japanese quail restrained for 30 min.

2. In control quail the highest concentrations were found in the a. hypothalamica posterior, n. periventricularis magnocellularis and n. hypothalamicus medialis anterior; the lowest was in the n. hypothalamicus medialis posterior.

3. After restraint, noradrenaline concentrations decreased in the n. periventricularis magnocellularis and n. hypothalamicus medialis posterior. However, the concentration of adrenaline increased in the n. tuberis under the same conditions. In stressed animals the dopamine concentration was lower than in controls in the n. periventicularis and higher in the n. tuberis.     

Early embryonic administration of xenoestrogens alters vasotocin system and male sexual behavior of the Japanese quail

The copulatory behavior and the parvocellular vasotocin (VT) system of the nucleus of the stria terminalis (BST) are sexually dimorphic in the Japanese quail. Embryonic administration of estradiol benzoate (EB) induces an organizational effect determining the disappearance of such a dimorphism (male shows behavior and cerebral phenotype of the female). The VT parvocellular system can therefore be considered an accurate marker of the sexual differentiation of brain circuits and a very sensitive indicator of the activity of estrogen-like substances on neural circuits. To test this hypothesis we administered diethylstilbestrol (DES), a powerful synthetic xenoestrogen, genistein (GEN), a phytoestrogen produced by soy, and bisphenol A (BPA). After 3 days of incubation, quail eggs were injected with vehicle, EB, DES, GEN or BPA. Administration of BPA caused an early blockage of development and no further analyses were done on the BPA groups. At puberty, the copulatory behavior of EB- or DES-treated male quail was totally abolished, whereas only the highest doses of GEN determined a significant decrease of the behavior. After the tests, the animals were sacrificed and perfused. The fractional area (FA) covered by VT immunoreactivity was analyzed in BST, medial preoptic nucleus, and lateral septum by computerized image analysis. The FA was significantly reduced after treatment with EB, DES and GEN at high doses. These results confirm that the sexually dimorphic VT system of the Japanese quail is a sensible indicator of the effects of xenoestrogens at the level of the central nervous system.     

Sertoli cell tumors in Japanese quail

Testicles were collected from 33 male Japanese quails older than 3 years. Three of these quails (9.1%) had one or two large neoplastic testicles. These testicles were 2-5 times normal size, round, and firm, with cystic spaces of various sizes. Microscopically, there was marked intratubular Sertoli cell proliferation and various-sized cystic spaces filled with an eosinophilic vacuolated fluid. Microscopic changes in all neoplastic testicles were diagnostic for Sertoli cell tumors.     

Effect of coccidiosis on pigmentation in broilers

Broiler chicks were fed on a high energy, commercial‐type ration with 20 g oxycarotenoids/ton¹ for 5 weeks. They were then transferred to two finisher rations: one with 20 g oxycarotenoids from the ingredients plus 3 g canthaxanthin/ton; the other containing 26 g oxycarotenoids/ton derived solely from the ingredients. Three replicated groups fed on each finisher ration were inoculated daily for 5 d with either 6000 sporulated oocysts of E. maxima, 30,000 sporulated oocysts of E. acervulina or no coccidial oocysts. The resultant mild infections caused reduced growth and impaired food conversion irrespective of the ration fed. Pigmentation, based on shank visual scores, plasma and toe‐web total carotenoid concentrations, was adversely affected in all infected groups. Groups fed canthaxanthin had higher visual scores than comparable groups not so supplemented; however, the presence of coccidiosis depressed flesh pigmentation proportionately in both groups judged by several pigmentation parameters. E. acervulina infection was as deleterious to the broiler as E. maxima, based on these criteria.     

Influence of various dietary protein levels on carcase composition in the male Japanese quail (Coturnix coturnix japonica)

1. The present study was conducted to determine the effect of various dietary protein concentrations on the carcase composition of male Japanese quail.

2. Six diets varying in protein from 160 to 300 g/kg and containing approximately 11–72 MJ/kg ME were fed for 5 weeks and analysed for dry matter, protein, fat and ash.

3. Treatments affected carcase weight, dry matter, protein, ether extract and ash

4. The water content of the carcases decreased with increasing dietary protein concentrations, while the carcase protein content increased with higher dietary protein. The carcases with the highest fat content were obtained from quail receiving the low protein diet.     

Protein requirement of laying Japanese quail.

1. Two feeding experiments were conducted to determine the crude protein requirement of laying Japanese quail. Birds were fed to provide 293 kJ ME and 2, 3, 4, 5, 6 or 7 g protein/d. 2. As protein intake increased from 2 to 5 g egg production increased. 3. Quadratic relationships between protein intake and egg production and protein intake and egg weight were derived. 4. To maintain a production of 90 eggs/100 bird d and an egg weight of 9.3 g required 4.9 g protein and approximately 264 kJ ME/d.