Seasonal variations on semen quality attributes in turkey and egg type chicken male breeders.

A biological experiment was carried out in twenty-four adult healthy breeder males each in turkey (Beltsville small white) and egg type chicken (White Leghorn Babcock) in order to assess the seasonal influence on semen production and quality. The birds were maintained in individual cages under uniform husbandry conditions throughout the year. The birds were fed with breeder ration and water ad libitum was offered with a constant photoperiod of 14 h/day. Physical and biochemical characteristics of semen, serum hormones (testosterone and thyroxine), and antioxidant activity (catalase and lipid peroxidation) were evaluated throughout the year (January-December). Based on the THI calculations, the observations were classified under three different seasons, namely, winter (November-February), spring (March, April, and October), and summer (May-September). Semen physical parameters, sperm concentration, motility, live sperm percentage, and sperm plasma membrane integrity were superior during the winter season. In seminal plasma, biochemical parameters (phosphorus, ALT, ALP, AST, and uric acid) had a significant (P < 0.05) difference between seasons. There was a significant difference (P < 0.05) among serum hormones (testosterone and thyroxine) that were higher during the winter season. Significant variation was observed in catalase and lipid peroxidation antioxidant enzyme activities (seminal and blood plasma) in winter than in the other two seasons. Both the turkey and egg type chicken breeders exhibited superior seminal characteristics, sex hormone profile, and antioxidant enzyme activity during winter seasons.

Effect of Supplementation of Zinc-Methionine on Egg Production, Semen Quality, Reproductive Hormones, and Hatchability in Broiler Breeders.

A biological study was conducted to explore the effect of zinc-methionine (Zn-Met) supplementation on productive, reproductive, and immunological response in broiler breeders. Adult healthy 45-week breeder males (192) and females (288) were used in a completely randomized design. Birds were randomly divided into four treatments consisting of six replicates and fed basal diet (control, 40 mg/kg), basal diet supplemented with Zn-Met 20 (T1), 40 (T2), and 60 mg/kg (T3). There was no effect (P > 0.05) on body weight and feed consumption among the breeders due to the supplementation of organic Zn. The T3 group had significantly (P < 0.05) higher semen volume, sperm motility, concentration, and live sperm count. The seminal plasma calcium and alkaline phosphatase activity were higher (P < 0.05), and total cholesterol and aspartate transaminase levels were low in the T3 group. Birds fed with additional supplementation of Zn (60 mg/kg) had improved both cellular and humoral immunity. Throughout the experimental period, the hen day egg production was comparable (P > 0.05) among the experimental groups. Organic Zn-supplemented group showed significant difference in both the internal and external egg qualities-albumen, yolk index, and shell thickness. The higher dose of organic Zn-fed groups had a significant difference in estrogen and progesterone concentration, and the highest testosterone concentration was observed in the T2 group. Supplementary organic Zn had a significant effect on the concentration of Zn and Cu in the seminal plasma. Serum Zn and Cu concentration was significantly increased due to the supplementation of organic zinc in both male and female breeders. The fertility and hatchability percentage were higher (P < 0.05) in the T2 group. It could be concluded that the additional supplementation of organic Zn (zinc-methionine) at 40 mg/kg to the basal diet improved the reproductive performance in broiler breeders.

Effect of polyphenol extract on performance, serum biochemistry, skin pigmentation and carcass characteristics in broiler chickens fed with different cereal sources under hot-humid conditions.

This study investigated the interaction between polyphenols with different cereal sources and their effects on performance, serum biochemistry, corticosterone levels and carcass characteristics in broiler chickens reared under hot-humid environment. Newly hatched coloured broiler chicks (n = 240) were randomly divided into six groups with five replicates of two different cereal sources, namely corn and broken rice-sorghum combined, and three levels of pomegranate peel polyphenol extracts (PPP) 0, 50 and 100 mg/kg in each cereal groups. Birds were maintained under standard management conditions for six weeks during hot-humid environment (Temperature: 29-36 °C; Relative Humidity: 69-80%). Fortnight body weight and feed consumption were recorded and serum biochemical constituents were estimated at 28 and 42 days of age. The body weight gain was significantly (p < 0.05) higher in broken rice-sorghum diet than in corn diet. The supplementation of polyphenols increased the skin and shank pigmentation. Serum protein, lipids and minerals showed significant difference due to cereals, polyphenols and their interactions. Corn-fed birds had significantly higher visceral organs weight than the alternate grain-fed broilers. The serum corticosterone levels were significantly reduced in the PPP supplemented groups than the control, it could be concluded that, supplementation of 50 mg/kg polyphenol extract from pomegranate peels improved production performance in broilers fed broken rice-sorghum as cereal source under hot-humid conditions.

Expression of gonadotropin and sex steroid hormone receptor mRNA in the utero-vaginal junction containing sperm storage tubules of oviduct during sexual maturation in Japanese quail.

Sex steroid hormones play an important role in reproductive tissue development of avian species. However, their role in Japanese quail is yet to be established. To understand the physiological role of hormones involved in the development of sperm storage tubules (SSTs) in quail, we investigated expression profiles of gonadotropin (LH-R and FSH-R) and sex steroid hormone (PR-R, ER-α and ER-ß) receptors in the uterovaginal junction (UVJ) containing SSTs before and during sexual maturation i.e. four to eight weeks. Every week four birds were sacrificed to collect blood and UVJ for sex steroid hormone (progesterone and estrogen) estimation and gene expression profiling of sex steroid hormone (PR-R, ER-α and ER-ß) and gonadotropin receptors (LH-R and FSH-R) using qRT-PCR. Receptor expression results showed that the expression of sex steroid receptor (PR-R, ER-α and ER-ß) genes were upregulated significantly (P < .05) in SSTs with the advancement of age. The expression of gonadotropin receptors (LH-R and FSH-R) was only high at week 5 and 6 respectively. Serum hormone analysis indicated a significant (P < .05) rise in estradiol till 7th week and progesterone from 7th week onwards. These results suggest that the gonadotropin and sex steroid hormone receptors may have the role in the development and maintenance of UVJ that contains predominantly SSTs during sexual maturation.

Effects of bisphenol-A on male reproductive success in adult Kadaknath chicken.

Bisphenol-A (BPA) adversely affects human and animal reproductive success in many ways, but this information is scant on birds. In the present study, we investigated the reproductive toxicity of BPA in adult Kadaknath chicken using two BPA dosages orally (1 or 5 mg/kg body weight) for seven weeks. In order to assess BPA toxicity, sperm functions, fertilizing ability, serum testosterone concentration and testis histopathology were measured in treated and control chickens. The semen volume was highest in birds exposed to 1mg/kg body weight BPA compared to other groups. 5 mg/kg body weight BPA reduced sperm concentration significantly more than other treatment and controls. However, overall fertility and testis histology were unaffected. These results indicate that BPA adversely affects sperm characteristics in adult kadaknath chicken without affecting fertilization potential.

Bisphenol A reduces fertilizing ability and motility by compromising mitochondrial function of sperm.

Bisphenol A (BPA) acts as an endocrine disruptor, affects animal reproductive success in vivo and affects sperm functions in vitro at environmentally relevant concentrations, leading to reduction in sperm motility and fertilizing ability in fish. The effect of in vitro BPA on avian sperm functions has not been explored. The present study examined the effect of environmentally relevant concentrations of BPA (0 mM, 0.18 mM, 0.37 mM, and 0.74 mM) on sperm functions in chicken in vitro. Sperm were exposed to concentrations of BPA for 30 min and analyzed for motility, fertilizing ability, live sperm percentage, and mitochondrial membrane potential (Δψm). Results showed that BPA at a concentration of 0.74 mM significantly decreased motility, fertilizing ability, live sperm count percentage, and sperm Δψm. Sperm motility was positively correlated with fertility (r = 0.73, p ≤ 0.01), live sperm percentage (r = 0.64, p ≤ 0.01), and high Δψm (r = 0.44, p ≤ 0.01). A dose-dependent and time-dependent effect of BPA was observed on sperm motility at all BPA concentrations. However, sperm's fertilizing ability was unaffected in low BPA concentration (0.18 mM and 0.37 mM). A significantly higher percentage of moribund sperm was observed at 0.37 mM and 0.74 mM BPA compared with at 0.18 mM BPA, in the negative control, and in the vehicle control. The present study confirms that environmentally relevant concentrations of BPA are capable of compromising sperm functions, leading to reduction in fertilizing ability of chicken sperm.

Norfloxacin drug induces reproductive toxicity and alters androgen receptor gene expression in testes and cloacal gland of male Japanese quail (Coturnix Japonica).

In an attempt to investigate the reproductive toxicity of norfloxacin in Japanese quail, male quail were given norfloxacin at 20 mg/kg body weight for 14 d. Then reproductive function and androgen receptor (AR) gene expression was examined in treated and control birds. The results of the present study indicate that fertility, cloacal gland area, sperm concentration, and serum testosterone were reduced significantly (p < 0.05) on day 14 in the norfloxacin-treated birds. Upregulation (p < 0.05) of AR mRNA was also seen in the testes on the 14th d of treatment. A trend toward downregulation of AR mRNA was seen in the cloacal gland of norfloxacin-treated birds. Histological observations revealed that norfloxacin induces cellular atrophy in testes and changes in glandular tissue in the cloacal gland. The results of the present study demonstrate that norfloxacin induces testicular toxicity in Japanese quail.

Protective effects of melatonin in reduction of oxidative damage and immunosuppression induced by aflatoxin B1-contaminated diets in young chicks.

In the present study, the ability of aflatoxin B(1) (AFB(1) ) to induce endogenous oxidative damages and the possible ameliorating effects of dietary melatonin (MEL) were investigated. Newly hatched broiler chicks (n = 240) were fed aflatoxin-contaminated diets (0.5 or 1 mg kg(-1) diet) with or without MEL (40 mg kg(-1) bw) supplementation in diet for 40 days. AFB(1) resulted in a significant increase in lipid peroxidation (LPO) in the liver and erythrocytes accompanied with suppression of superoxide dismutase (SOD) and catalase (CAT) enzyme activities of erythrocytes. It also caused a significant reduction in levels of serum proteins and marked elevation in activities of serum transaminases. AFB(1) treatment also decreased both humoral and cell-mediated immune responses in growing chicks. Simultaneous administration of MEL with AFB(1) resulted in an obvious improvement in all the tested parameters. Long-term rather than short-term administration of MEL was more effective in rendering protection against AFB(1)-induced toxicity.

Characterization of lactate dehydrogenase enzyme in seminal plasma of Japanese quail (Coturnix coturnix japonica).

Lactate dehydrogenase enzyme present in quail seminal plasma has been characterized. Polyacrylamide gel electrophoresis and subsequently with LDH specific staining of seminal plasma revealed a single isozyme in quail semen. Studies on substrate inhibition, pH for optimum activity and inhibitor (urea) indicated the isozyme present in the quail semen has catalytic properties like LDH-1 viz. H-type. Furthermore, unlike other mammalian species, electrophoretic and kinetic investigations did not support the existence of semen specific LDH-X isozyme in quail semen. The effect of exogenous lactate and pyruvate on sperm metabolic activity was also studied. The addition of 1 mM lactate or pyruvate to quail semen increased sperm metabolic activity. Our results suggested that both pyruvate and lactate could be used by quail spermatozoa to maintain their basic functions. Since the H-type isozyme is important for conversion of lactate to pyruvate under anaerobic conditions it was postulated that exogenous lactate being converted into pyruvate via LDH present in semen may be used by sperm mitochondria to generate ATP. During conversion of lactate to pyruvate NADH is being generated that may be useful for maintaining sperm mitochondrial membrane potential.

The effect of different foam concentrations on sperm motility in Japanese quail.

A study was conducted to determine the effect of foam extract on sperm motility in the male Japanese quail (Coturnix coturnix japonica). Adult male quails (<12 weeks) of heavy body weight strain were housed in individual cages and divided into 5 groups according to the size of their cloacal glands. The data indicated that the size of the cloacal gland was positively correlated with the frequency of foam secretion and total foam production. One gram of freshly collected clean foam was mixed with 1.0 mL of normal saline and homogenized for 10 minutes. After centrifugation at 35 000 rpm, the supernatant was used as 100% foam extract. The extract was diluted to 1:40, 1:20, 1:10, and 1:4 with normal saline to produce 2.5, 5.0, 10, and 25% foam extracts, respectively. 5% foam extract enhanced sperm survival at room temperature (30°-35°C) for 2 to 3 hrs, whereas higher concentrations (10% and above) suppressed sperm motility. From this study, it may be concluded that foam secretion and quantity of foam are directly proportional to the size of the cloacal gland and that the foam enhances and prolongs sperm motility, in vitro at an optimum concentration of 5%.

Age-dependent variation in hormonal concentration and biochemical constituents in blood plasma of Indian native fowl.

This experiment was to investigate the age-related changes in hormonal concentration and biochemical constituents of blood plasma in Indian native desi fowl. One hundred and sixty two (54 from each breed, i.e., Kadaknath (KN), Aseel peela (AP), and White leghorn (WLH)) day-old female chicks were randomly divided into nine groups each of 18 chicks (3 groups × 3 replicates). WLH was taken in this study to compare the characteristics of Indian native desi fowl. The highest level of estrogen hormone in WLH and desi fowl in blood plasma was occurred at 18 and 24 wks of age, respectively. Whereas, the peak of progesterone hormone in WLH hens noticed around 24 wks, in case of desi fowls, it was at 30 wks of age. Irrespective of the breed, the hormonal profile of Triiodothyronine (T3) and Thyroxine (T4) in blood plasma was found highest around 6 to 12 wks of age. Activities of acid phosphatase (ACP) increased with the reduction of alkaline phosphate (ALP) activities at different time intervals. Irrespective of the breed, transaminases (glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT)) activities of blood plasma increased linearly with the advancement of the age. From this study, it may be concluded that sexual maturity of the Indian native desi fowl occurred nearly 6 wk later (24 wk) than WLH.

Effects of simulated hypo- and hyper-reproductive conditions on the characteristics of circadian rhythm in hypothalamic concentration of serotonin and dopamine and in plasma levels of thyroxine, triiodothyronine, and testosterone in Japanese quail, Coturnix coturnix japonica.

In this study, hypo- and hyper-reproductive conditions, as measured by concentrations of plasma testosterone in male Japanese quail held on long days LD 16:8, were experimentally simulated with injections of 5-hydroxytryptophan (5-HTP) and L-dihydroxyphenylalanine, (L-DOPA) with 8 h and 12 h phase angle differences between them in intact and melatonin-treated birds. The effects of these treatments were assessed on the characteristics of the circadian rhythm in the hypothalamic concentration of serotonin (5-HT), dopamine (DA), and plasma levels of thyroxine (T(4)), triiodothyronine (T(3))(,) and testosterone (T). These rhythms were also studied in sham-operated (SO), pinealectomized (Px), vehicle- (Veh), and melatonin (Mel)-treated birds. On the basis of the circadian mesors of the testosterone rhythms, three distinct categories could be identified: category A (i.e., normal breeding concentrations of plasma testosterone), which includes control, sham-operated, and vehicle-treated groups; category A(+) (i.e., concentrations of plasma testosterone higher than that found in normal breeding quail), which includes 12 h, 12 h+vehicle-treated, and Px quails; and category A(-) (concentrations of plasma testosterone lower than that found in normal breeding quail), which includes 8 h, melatonin-, and 12 h+melatonin-treated groups. It is evident that in normal and hypergonadal conditions (i.e., birds belonging to categories A and A(+)) the circadian rhythm in hypothalamic serotonin maintained a positive phase angle of about 16 h. In contrast, birds of category A(-) (i.e., in a hypogonadal condition) exhibited a negative phase angle of about 2 h. The present results clearly suggest that the internal phase relationship between the circadian rhythms in hypothalamic serotonin and dopamine might play a crucial role in strategizing and conferring a particular reproductive status to the birds. The role of circadian mechanisms involving circulating thyroid hormones in conferring reproductive status is completely ruled out, as no definite internal phase angle between these two hormonal rhythms was witnessed vis-a-vis different treatment groups. The testosterone peaks always occurred at the same time irrespective of breeding status of the bird, but with significant variation in its amplitude (high in hypergonadal and low in hypogonadal condition). It is suggested that administration of 5-HTP and L-DOPA at specific time interval and variation in pineal functions that modulate reproductive responses also alter the circadian pattern (acrophase and amplitude) of hypothalamic serotonin and dopamine, maintaining a specific phase relation between these cycles and breeding status. These findings strengthen our previous reports that a specific circadian phase relation of serotonergic and dopaminergic oscillations regulates reproduction. The present study strongly supports interdependence and specific relation of the two systems (gonadal activity and circadian pattern/phase relation of neural oscillation) in both natural and experimentally simulated conditions.

Role of nitric oxide in ovarian follicular development and egg production in Japanese quail (Coturnix coturnix japonica).

Role of nitric oxide (NO) in regulating the reproductive functions at hypothalamo-hypophysealovarian axis in Japanese quail was studied. In first experiment, metabolites of NO, i.e. nitrite and nitrate (NO2 and NO3) were estimated together in hypothalamus, serum and ovarian follicles of good and poor layers. In the second experiment, different NO modulators such as L-arginine (L-Arg), sodium nitroprusside (SNP) and N(G)-nitro-L-arginine methyl ester, HCl (L-NAME) were administered to the birds. In the first experiment, significantly higher (P < 0.01) NO2 and NO3 levels in serum, hypothalamus and largest (F1) ovarian follicles were observed in good layers as compared to poor layers. Higher (P < 0.05) NO2 and NO3 concentration was observed in F1 follicles than smaller follicles (F2) only in good layers. The NO2 and NO3 concentration was significantly reduced (P < 0.05) in post ovulatory follicles (POFs) in comparison to F1 and F2 follicles. In the second experiment, the serum NO2 and NO3 concentrations were higher (P < 0.05) in the SNP, lower (P < 0.05) in the L-Name group and unchanged in the L-Arg treated group in comparison to control group. compared to control, L-Arg and SNP increased (P < 0.05) the hypothalamic NO2 and NO3 concentration where as L-NAME reduced (P < 0.05) these levels. The NO2 and NO3 concentration was increased (P < 0.05) as the follicle size increased and it was significantly reduced (P < 0.05) in POFs. The higher (P < 0.05) follicular NO2 and NO3 concentration was observed in L-Arg group in comparison to control group. Egg production was also found to be higher (P < 0.05) in L-Arg group whereas it was not different (P > 0.05) in SNP and L-NAME treated groups. The yolk weight and yolk to albumin ratio was reduced (P < 0.05) in L-NAME group in comparison to control group. It may be concluded from the present study that NO plays a key role in regulating follicular development, ovulatory mechanisms and egg production in Japanese quail.

Isolation of E. coli from foam and effects of fluoroquinolones on E. coli and foam production in male Japanese quail.

Sexually active male Japanese quail (Coturnix coutrnix Japonica) produce a foamy substance from their cloacal gland. It was postulated that bacteria played an important role in production of foam. The primary objective of this study was to isolate and identify bacteria present in the cloacal foam. The secondary objective was to evaluate the effect of fluoroquinolone treatment on bacterial counts and foam production. Healthy adult Japanese quail were maintained in individual cages under uniform husbandry conditions and allocated arbitrarily into three groups (each group consisted of 12 male and 12 female birds). Foam was collected from the cloacal gland of male birds of each group separately into sterile petri dishes and was cultured to isolate and identify bacteria and to determine their sensitivity to various antibiotics. Escherichia coli bacteria, sensitive to various antibacterials (including the fluoroquinolones ciprofloxacin and pefloxacin), were isolated. In the second part of the study, male quails of Group I (control) received I mL vehicle (normal saline 0.9% (w/v) NaCl) daily (via the intraperitoneal route) for 12 days. Male birds from groups II and III were treated intraperitoneally with ciprofloxacin or pefloxacin at the rate of 10 mg and 12 mg per/kg body weight respectively, for 12 days. In antibiotic-treated birds, there was a gradual reduction in foam production during treatment. At the end of treatment, the cloacal gland area was smaller (P < 0.05) in pefloxacin-treated birds compared to the other groups. Furthermore, a trend towards decreasing body weight and fertilizing ability was noted in the same group. A drastic reduction in bacterial counts of foam was recorded only in fluoroquinolone-treated groups during treatment period. After cessation of treatment, all end points were increasing back to pre-treatment levels. In conclusion, E. coli were present in the foam of the cloacal gland of Japanese quail and may have a role in foam production.

Effects of hemicastration and castration on foam production and its relationship with fertility in male Japanese quail.

Healthy heavy body weight strain of adult male Japanese quail (Coturnix coturnix Japonica) of the same age were used in this study to observe the effect of hemicastration and castration on the frequency of foam discharges from cloacal gland and other related parameters. The quails were housed in individual cages and divided into four groups: control (intact birds), sham-operated control (intact birds with incision), hemicastrated, and castrated groups of birds. Hemicastration and castration were carried out surgically at 10 and 13 weeks of age, respectively. Subsequently, 3 weeks after castration birds were examined for different parameters. Hemicastration caused a significant (P < 0.05) drop in the foam discharge frequency, weight of the foam, and the level of testosterone in the plasma, whereas in castrated group these variables were observed nil or negligible as compared to both of the controls. A suppressive effect of hemicastration was also noticed on the body weight, area of the cloacal gland, as well as percent fertility. Castration induced the drastic regression of the cloacal gland and a significant reduction (P < 0.05) of the body weight was also noted as compared to other groups. Frequencies of foam discharges were twice the number in daytime (06:00-18:00 h) than night, irrespective of the groups. In another study, the effect of characteristics of foam or foam glands on fertility was examined in 77 male birds paired with females. Several characteristics of foam and foam glands were examined for infertility, such as light yellow foam, dark yellow foam, smaller area of foam gland (below 225 mm2), hardness of foam gland and certain unknown factors that contributed 0.23, 0.68, 5.23, 2.27 and 3.64% infertility, respectively. An overall 12.1% birds were found to be infertile. This data indicated that smaller sizes of foam glands might reflect the poorest fertilizing ability of the male birds. From this study, it may be concluded that the cloacal gland may be considered as an external indicator of testicular function of the birds. Characteristics of the cloacal gland or foam or both may be used as a simple and effective tool to predict the fertilizing ability of an individual male in view of the very small semen ejaculate that is very difficult to collect and evaluate for fertility.