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1.
The objective of this study was to detect the reasons of rooster's fertility decrease at 50 weeks of age. Therefore, the reproductive system of broiler breeder roosters was laparoscopic, macroscopic and histopathology evaluated, and a comparison of the anatomical aspect with the sperm analysis and birds’ age was realized. Cobb roosters (n = 59) were distributed into two groups (30 and 50 weeks). Evaluations were performed with laparoscopy, macroscopy and histopathology, and seminal quality, blood serum testosterone concentration and weight were also determined. The old roosters presented smaller testicle size, higher intensity epididymal lithiasis and lower testicle sperm production, compared to the young roosters. The use of the endoscope could easily distinguish a normal‐sized testicle than an atrophic one. Four old roosters with severe testicular atrophy did not show spermatogenesis, although three still had sperm in the ejaculate. This would falsely indicate a wrong diagnosis of normal fertility before the testicular atrophy took place. In conclusion, in addition to the weight increase with age, the testicular atrophy and impairment of sperm production seemed to be the main reason to the decrease in the rooster's fertility at 50 weeks of age. Therefore, the use of the laparoscopy as a way to detect the roosters with testicular atrophy before 50 weeks of age and their removal from them flock could be useful as a diagnostic tool to prevent the birds’ fertility loss.  相似文献   

2.
Fertility of domestic roosters decreases at ∼50 wk of age. In a previous study on aging white leghorn roosters, low fertility was accompanied by low levels of both hypothalamic vasoactive intestinal peptide (VIP) and pituitary prolactin (PRL) mRNA expression; however, their role in aging broiler breeder rooster reproduction is still unclear. In this study we compared reproductive activities of young (35-wk-old) and aging (73-wk-old) broiler breeder roosters. Weekly semen volume; concentration and ejaculation grade; and concentrations of plasma testosterone, estradiol, and PRL were examined. Every other week, 10 roosters from each group were euthanized, their testes weighed, and hypothalamus and pituitary removed to determine mRNA expression of hypothalamic GnRH-I, pituitary FSH, pituitary LH, hypothalamic VIP, and pituitary PRL. Aging roosters had significantly lower testis weight and semen volume, sperm concentration, ejaculation grade and plasma testosterone and low hypothalamic GnRH-I, pituitary FSH, and pituitary LH mRNA expression than young roosters (P ≤ 0.05). Aging roosters had higher concentrations of plasma estradiol and PRL and higher hypothalamic VIP and pituitary PRL mRNA expression than young roosters (P ≤ 0.05). We suggest that PRL, which is known to inhibit the gonadal axis, and its releasing factor, VIP, play an important role in the reproductive failure associated with age in broiler breeder roosters.  相似文献   

3.
Age negatively affects reproductive success of broiler breeder flocks. One of the main hormones involved in the change of fertility with the age is testosterone (TT). The introduction of young males at later production stages of broiler flocks is known as spiking and is expected to reduce the fertility decline with age. The aim of this study was to determine the effect of injection of different levels of TT and the effect of spiking on reproductive fitness of broiler breeder flocks. Two experiments were conducted on Ross 308 breeder flocks for 10 weeks (41–50 weeks of age). The experiment 1 included a control and three treatments corresponding to three doses of TT (0.1, 0.2 and 0.3 cc), while the experiment 2 included a control and one treatment corresponding to spiking. The lower dose of TT (0.1 cc) and the spiking clearly slowed down the decline in hatchability. Therefore, either the external administration of TT to the males when the natural concentration of TT starts to decline or spiking the breeder flock with young roosters could contribute to improve reproductive success in later stages of the production cycle in broiler breeder flocks.  相似文献   

4.
The objective of this study was to evaluate the effect of dietary supplementation of whole flaxseed on sperm traits and sperm fatty acid profile in aged broiler breeder roosters. Twelve Ross 308 broiler breeder roosters (age: 52 weeks; weight: 4,900 ± 210 g) haphazardly allotted to three dietary treatments (each treatment contained four replicates and one bird in each replicate) for six weeks. Treatments were different levels of flaxseed (0% flaxseed [GFL0], 2% flaxseed [GFL2] and 4% flaxseed [GFL4]). The feed intake quadratically decreased (p < .05) with increasing whole flaxseed levels for the period (58 to 60 weeks). Sperm traits (semen volume and sperm concentration, sperm total and forward motility, sperm viability and morphology, sperm plasma membrane functionality) were evaluated every two weeks (four times), and sperm fatty acid profile was assessed at the end of the experiment. Semen volume, sperm concentration and sperm morphology were not affected by treatments. On week 60, GFL2 group showed a significantly lower percentage of total and progressive sperm motility and sperm membrane functionality in comparison with the control and GFL4 groups. Also, sperm viability was lower in GFL2 group compared with other groups on week 58 (p < .05). In terms of sperm fatty acid profile, GFL2 group significantly reduced the percentage of linoleic acid (C18:2 [n-6]) in comparison with other groups. However, any of the other fatty acids were not affected by dietary flaxseed. In conclusion, dietary supplementation of whole flaxseed could not improve the quality of aged broiler breeder roosters' sperm in this study, nor it could alter the sperm fatty acid profile; thus, it seems necessary to use some antioxidants such as vitamin E in the diet of aged broiler breeder roosters, when supplementing the diets with oils or oilseeds such as flaxseed.  相似文献   

5.
1. Genetic selection for growth to enhance production may be associated with stress and with modified physiological and behavioural phenotypes which depress male primary broiler breeder fertility. 2. We hypothesised that male serum testosterone (T) and corticosterone (C) concentrations might correlate with fertility, sexual behaviour, and testicular, comb and wattle size. 3. Cockerels from two genetic strains (A and B) of primary broiler breeder were penned individually with an average of 10 females across 5 age periods (30 to 51 weeks) to evaluate male fertility, behaviour, serum T and C, and comb, wattle and testicular dimensions. 4. Strain A males had higher T at age periods 2, 4 and 5 than Strain B. Both strains had basal concentrations of C, apart from an elevated concentration for Strain B in period 5. 5. Strain B had a weak but significant, positive correlation between sexual behaviour and T and C, while Strain A males with higher C had larger combs and wattles. 6. Neither T nor C correlated with fertility. We conclude that evaluation of these endocrine factors (quantifiable measurements with the potential to correlate with fertility) alone seems insufficient to predict male fertility potential in these strains of primary broiler breeder.  相似文献   

6.
1. Broiler breeder males were reared on 8-h photoperiods, transferred to 12 h at 20 weeks, and either maintained on 12 h or further transferred to 14, 16, 18, 20 or 22 h at 40 weeks to determine whether reproductive status and the timing of the onset of adult photorefractoriness is influenced by photoperiod during the breeding cycle. 2. No photoperiodic effect was observed on sperm concentration although the combination of large variation within a treatment and the lack of a semen sample from some males at each collection may have masked small differences and indicates that perhaps fertility in individual males fluctuates naturally during the breeding season. 3. The rate of comb growth to, and testicular weights at, 60 weeks were not significantly different between treatments. 4. Plasma testosterone concentration at 60 weeks of age declined linearly with photoperiod between 12 and 22 h, suggesting that in the birds exposed to the more stimulatory photoperiods after 40 weeks, hypothalamic-pituitary-gonadal activity shut down earlier. 5. An increase in photoperiod at 40 weeks of age appears to advance the onset of photorefractoriness in male broiler breeders, evident from the decline in testosterone concentration with increasing photoperiod; it is however insufficient to affect sperm concentration or comb area.  相似文献   

7.
Boltz DA  Nakai M  Bahra JM 《Avian diseases》2004,48(4):909-915
The formation of epididymal stones in the rooster epididymis is a widespread problem that has detrimental effects on sperm production and fertility. The cause of epididymal stones is unknown, but an infectious agent, the avian infectious bronchitis virus (AIBV), has been implicated. The goal of this study was to determine if administering the live attenuated AIBV vaccine to male chicks increases the incidence of stones in the epididymal region of the adult rooster. Specific pathogen free (SPF) Leghorn roosters were divided into two groups: a vaccine-free group (n = 7) and a group vaccinated with AIBV (n = 12). The vaccine was administered orally at 2, 4, 10, and 14 wk of age. Blood was drawn weekly to monitor antibodies to AIBV. At 26 wk of age, blood was obtained to determine testosterone concentrations, and reproductive tracts were removed to analyze daily sperm production and to detect epididymal stones. Nine of 12 vaccinated roosters developed stones, whereas those not given the vaccine did not develop stones. Serum testosterone concentrations were significantly (P < 0.05) reduced in vaccinated roosters with epididymal stones (3.6 +/- 0.30 ng/ml) when compared with nonvaccinated roosters that did not have epididymal stones (7.0 +/- 1.63 ng/ml). Testis weight was significantly (P < 0.05) reduced in vaccinated roosters with epididymal stones (12.1 +/- 0.76 g), as compared with nonvaccinated roosters without epididymal stones (15.2 +/- 0.81 g). Daily sperm production was significantly (P < 0.05) decreased in vaccinated roosters with epididymal stones (5.03 +/- 0.31 x 10(8) sperm/testis/day) when compared with nonvaccinated roosters without epididymal stones (7.43 +/- 0.52 x 10(8) sperm/testis/day). Comparing daily sperm production on a per gram basis, vaccinated roosters with epididymal stones had 4.38 +/- 0.14 x 10(7) sperm/g of testis, which was significantly (P < 0.05) smaller than nonvaccinated roosters without epididymal stones, which had 5.17 +/- 0.17 x 10(7) sperm/g of testis. We conclude that the use of a live attenuated AIBV vaccine increases the incidence of epididymal stones in roosters, resulting in decreased sperm production and decreased serum testosterone concentrations.  相似文献   

8.
(1) Tolerance to ad libitum feeding was compared in three genotypes of broiler breeder hens: a standard broiler breeder fed ad libitum (SA) or restricted (SR), a slow growing 'label' broiler breeder (L) and an experimental dwarf heavy broiler breeder (E). Two similar experiments were conducted in two distinct research centres. (2) Feed intake and body weight were measured every 3 weeks from hatch to 40 to 49 weeks of age. Egg production and egg abnormalities were recorded. The number of yellow follicles in ovaries was counted at the age of 32 weeks. (3) Body weight was stabilised at 2.2, 3.7 and 5.4 kg after 24 weeks of age in L, E and SA hens, respectively. Growth of the SR hens was similar to that of L up to 20 weeks and stabilised at a similar level to that of E hens after 30 weeks of age. (4) Sexual maturity was delayed by 6 weeks in restricted breeders compared to ad libitum fed hens that started to lay at 20 weeks. SA hens had low egg production and a high proportion of defective eggs, which was largely compensated for by feed restriction. However, productivity of SR hens remained lower than that of L breeders. (5) Compared to the low viability and reproductive fitness observed with SA hens, the E dwarf broiler breeder tolerated ad libitum feeding and had better egg production, fewer egg abnormalities and yellow follicles per ovary and a higher egg production. However, laying rate was still lower than that of the SR and L groups. Energy conversion (kJ/g egg) from 32 to 40 weeks of age was much higher in the SA group than in the other three groups. 6. The feasibility of feeding a dwarf broiler breeder ad libitum calls for further research on implications of specific IGF and GH-receptor expression at the level of the ovary in dw chickens.  相似文献   

9.
Reproductive efficiency of male broiler breeders declines toward the end of a production cycle. It is common to add young, replacement males (spiking) to a breeder flock to maintain or increase fertility. To date, no study has reported if there are differences in the carcass and reproductive morphology between original and spiked males at the end of the breeding period. In this study, the weight, fleshing traits, footpad condition, and testes size of 327 Hubbard males (237 original and 90 replacement) from a commercial operation were examined. The original birds (63 wk of age) had significantly higher BW, breast weight, girth measurement, keel length, and spur length than the spiked males (48 wk of age). While external indicators of size and fleshing differed betweenreplacement and original roosters, testis weight was not affected by the age of the bird. It was found that average testis weight correlated well with BW in birds in which testicular regression had not taken place but only weakly with spur length. Because original males had a higher BW and were more heavily fleshed than replacement males, their ability to successfully complete matings may have been impeded. Further research is needed to link growth profiles with semen quality, sexual behavioral, and longevity of a male breeder in a commercial flock.  相似文献   

10.
In order to assess the effects of subgroup J avian leukosis virus (ALV-J) on semen quality, broiler breeder males were separated by ALV-J status (ALV-J positive = POS, ALV-J negative = NEG) at 44 wk of age. Of the 249 males originally placed at 1 day of age, 101 (40.6%) died by 43 wk of age. Observations of tumor expression and high mortality suggest that many of the males that died prior to 44 wk of age were infected with ALV-J. From 47 to 56 wk of age, hens were inseminated every third week with 7.5 x 10(7) sperm. Fertility and hatch data were collected by incubating eggs laid during the 2 wk postinsemination (WPI). The number of sperm that penetrated the perivitelline membrane of the ovum was determined from eggs laid on the eighth day postinsemination. Sperm mobility index (SMI) was determined at 58 and 60 wk of age from all males producing semen. Whereas SMI and sperm hole penetration measurements indicated that the sperm quality from treatments POS and NEG were similar, fertility was significantly greater in the POS treatment during the first (89.0% vs. 79.0%) and second WPI (59.3% vs. 45.0%). However, because of numerically higher hatch of fertile from the NEG group, the percentage of hatch of eggs set was similar between groups. These data suggest that ALV-J status of caged males has no influence on sperm quality or hatchability of eggs.  相似文献   

11.
Two experiments were conducted to evaluate the effects of feeding guanidinoacetic acid (GAA) and L‐arginine (ARG) on fertility and sperm penetration (SP) rate of broiler breeder hens. In the first experiment, a total of 200 broiler breeder hens (Ross 308) aged 53 week were randomly allotted to four dietary treatments (0, 0.6, 1.2 and 1.8 g GAA/kg diet) with five replicates of 10 birds each. In the second experiment, 320 broiler breeder hens (Ross 308) were used from 53 to 62 weeks of age in a 2 × 4 factorial arrangement (0 or 1.2 g GAA/kg diet along with 0, 3, 6 or 9 g ARG/kg diet). The hens received a diet containing 2800 kcal ME/kg and 14% CP. Sixteen sexually mature Ross 308 breeder roosters (34 weeks old) were used to artificially inseminate the hens. Fertility of the hens was determined in 61 and 62 weeks of age. The sperm penetration holes in the inner perivitelline layer (IPL) overlying the germinal disc were enumerated on days 3 and 7 following each insemination. Adding GAA to the breeder diet increased the number of SPs in the IPL and fertility in both experiments (p < 0.01). The interactive effect of ARG and GAA on the SP and fertility was significant. Supplementary ARG increased the SP rate in the IPL (p < 0.01). In conclusion, dietary supplementation of GAA and ARG might be potentially used to improve the fertility of broiler breeder hens at the later phase of the egg production period.  相似文献   

12.
Peracute onset of disease was reported in a 42-wk-old broiler breeder flock that was presented by error with feed containing monensin at approximately seven times the approved level for broiler chickens. Morbidity and mortality were extremely high, and the affected chickens displayed feed refusal, decreased water consumption, and severe paralysis that ranged from abnormal gait to a complete inability to move. During the first 10 days postingestion of the suspect feed, mortality in hens reached 13.7% and 70.9% in the roosters. Hen day production decreased from 67% to 3% in the same period of time. A total of 638 g/ton of monensin was detected in suspect feed samples by one laboratory and 740 g/ton in a second laboratory. Twenty-one days after removal of the suspect feed, the mortality rate returned to normal levels in both hens and roosters, albeit feed consumption and egg production remained extremely low, which prompted the company involved to eliminate the flock.  相似文献   

13.
ABSTRACT

1. Deleterious effects from the freeze-thawing process on post-thawed sperm quality attributes are main limiting factors in cryopreservation. The current study was conducted to determine the effect of semen extender containing zinc oxide (ZnO) on post-thaw rooster sperm quality indices.

2. Semen samples from six, 60-week-old broiler breeder roosters were collected weekly during five successive weeks. The samples were mixed and divided into three equal parts and diluted with semen extender containing different levels of ZnO; 0 (ZnO-0), 1 (ZnO-1) or 2 (ZnO-2) µg/ml. After thawing, motility and velocity parameters, plasma membrane functionality, apoptotic like changes, mitochondrial membrane potential (MMP), and DNA fragmentation index (DFI) were evaluated.

3. Results showed that the addition of ZnO in the extender quadratically affected (P < 0.01) total motility (TM), progressive motility (PM), and average path velocity (VAP) with the highest values were noted in the ZnO-1 group. Levels of ZnO quadratically affected percentages of live (P < 0.01), apoptotic (P < 0.03) and dead (P < 0.10) spermatozoa, where the highest percentage of live, and the lowest percentage of apoptotic or dead spermatozoa was for the ZnO-1 group. Although adding ZnO quadratically affected plasma membrane functionality and MMP (P < 0.01), it did not affect (P > 0.05) DFI.

4. In conclusion, there were some beneficial effects of ZnO supplementation in semen extender on post-thawed rooster sperm quality which may result in a better freezability.  相似文献   

14.
Enterococcus cecorum is the most frequently occurring enterococcal species in the intestine of chickens of over 12 weeks of age, and there are few reports on its isolation from the skeleton of broiler parent chicks. In the present study, observations on vertebral osteomyelitis and spondylolisthesis ('kinky back syndrome') showing high incidence in 8 broiler parent flocks in different parts of Hungary are summarised. Clinical signs were seen only in roosters between 5 and 13 weeks of age. Diseased birds were alert and remained sitting on their hocks with their feet slightly raised off the ground. Incidence of the disease among male birds ranged from 8% to 30% depending on flocks. Enlargement and distortion of the body of the 6th vertebra were seen as the main pathological lesions. The cavity of the spinal canal was constricted by the distorted vertebral bodies. Resorption of bone tissue and sequestrum formation, signs of increased osteoclast activity, proliferation of fibrotic tissues, infiltration with heterophils and formation of sclerotic layers were detected in the vertebral bodies. From all 24 samples collected from the vertebral lesions, Enterococcus cecorum was isolated and identified using metabolic fingerprinting as well as 16S rRNA gene sequencing. Demonstration of E. cecorum from the vertebral lesions in all examined broiler breeder roosters showing the same clinical and pathological findings in different flocks suggested the pathogenic role of this microorganism for the first time in Hungary.  相似文献   

15.
16.
1. An experiment was conducted utilising 480 eggs from broiler breeder hens to determine the effect of oviposition and parental age on 1-d-old chick weight when egg weight remained constant. 2. Neither the age of the breeder flock nor the time of oviposition had a significant effect on egg weight loss during the 18 d of incubation. Nor was there any effect on chick weight: egg weight ratio and 1-d-old chick weight when chicks were removed and weighed at the same time. 3. Hatching time was significantly affected by time of oviposition and age of parents. Afternoon eggs or eggs from older hens tended to hatch earlier than morning eggs or eggs from younger ones.  相似文献   

17.
A new quantitative trait affecting male fertility was discovered in the 1990s. The term sperm mobility denotes the net movement of a sperm cell population against resistance at body temperature. Even though sperm cells are self-propelled DNA delivery vehicles, their self-propulsive nature is neither uniform among sperm within an ejaculate nor among males within flocks. Such variation is evident when semen quality is evaluated by sperm penetration of an Accudenz solution, hence the term sperm mobility assay. It is noteworthy that populations showing modest variation with respect to semen volume or sperm concentration often show considerable variation with respect to sperm mobility. Likewise, it is noteworthy that broiler breeder fertility is a function of sperm mobility phenotype when hens are inseminated artificially. This article outlines the following: 1) a series of experiments in which the sensitivity of the commercial sperm mobility assay was improved using semen donors from lines of chickens selected for either low or high sperm mobility and 2) the application of the improved technique to pedigree broiler breeders. Male fertility is subject to genetic selection when sperm mobility is the selection criterion. Therefore, sperm mobility may be a useful trait for improving broiler breeder reproductive efficiency.  相似文献   

18.
At 45 wk of age, 99 roosters housed in individual cages were tested for avian leukosis-J strain virus (ALV-J); 32 tested positive and 67 tested negative. These roosters were fed a restricted diet to maintain weight to primary breeder specifications. Individual semen and ceca samples were analyzed for presence and level of Campylobacter. Population levels of Campylobacter in semen and ceca of ALV-J individuals were 3.5 times higher than negative birds. Controlling viruses such as ALV-J may be an important part of limiting colonization of broiler breeders by organisms such as Campylobacter.  相似文献   

19.
Campylobacter is considered to be the leading bacterial etiologic agent of acute gastroenteritis in humans. Evidence implicates poultry as a major source of the organism for human illness; however, the pathways involved in Campylobacter contamination of poultry flocks, horizontal transmission and/or vertical transmission, remain unclear. Recent evidence implicates breeders as a potential source for Campylobacter contamination of the subsequent broiler offspring. In this investigation, Campylobacter isolated from feces, cloacal swabs, ceca, semen, and vas deferens of 12 breeder broiler roosters were genotyped by both flagellin A short variable region (flaA SVR) DNA sequence analysis and repetitive element (rep)-polymerase chain reaction (PCR). In 9 of 12 roosters, Campylobacter was isolated from multiple sites sampled. Comparison of multiple isolates obtained from individual roosters revealed variable results. In five of the nine roosters, all Campylobacter isolated demonstrated closely related flaA SVR DNA sequences as well as rep-PCR patterns; isolates from these roosters were collected from both the gastrointestinal and the reproductive tracts or from the gastrointestinal tract alone. The remaining four roosters had Campylobacter that were distinct by both typing methods. Isolates from two of these four roosters originated from both the gastrointestinal and the reproductive tracts. Isolates from the remaining two roosters originated from only the reproductive tract. Comparisons of all Campylobacter isolates recovered from a distinct sample type within either the reproductive tract or the gastrointestinal tract (feces, semen, cloaca, vas deferens, or ceca) were quite diverse. No relationship between the genotypes and the sample type could be ascertained. Further investigation is needed to determine the route of contamination and if the presence of Campylobacter within the rooster leads to contamination of the broiler offspring via the fertilized egg.  相似文献   

20.
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