Broiler Breeder Roosters Research Articles

Improvement of post-thawed sperm quality in broiler breeder roosters by ellagic acid-loaded liposomes

ABSTRACTLiposomes could improve the delivery of substances to sperm. This study was conducted to investigate the effect of the antioxidant ellagic acid and ellagic acid-loaded liposomes on post-thawed sperm quality in broiler breeder roosters. Semen was diluted in Beltsville extender containing ellagic acid or ellagic acid-loaded liposomes (ellagic acid at 0 (control), 0.5, 1, and 2 mM) and cryopreserved. Sperm quality was evaluated post-thawing: motility characteristics (Computer-Assisted Semen Analysis), membrane functionality (HOS test), abnormal morphology, mitochondrial activity (Rhodamine 123), apoptotic status (Annexin V/Propidium iodide), malondialdehyde, and antioxidant activities (glutathione peroxidase (GPx), superoxide dismutase (SOD), and total antioxidant capacity (TAC)). The results showed that 1 mM ellagic acid-loaded liposomes improved total motility, membrane functionality, and viability comparing to 0.5 and 2 mM ellagic acid, 2 mM ellagic acid-loaded liposomes, and control group. Mitochondrial activity was significantly higher for 1 mM ellagic acid-loaded liposomes compared to the rest of the treatments, except 1 mM ellagic acid. Ellagic acid at 1 mM in both forms significantly increased GPx and TAC after freeze-thawing (no significant variation for SOD), and also yielded the lower proportion of apoptotic and dead cells. In conclusion, ellagic acid improved post-thawed sperm quality in broiler breeder roosters. The use of liposomes could further enhance the effects of ellagic acid.

Correlation of Plasma Lipids' Profile with Testicular Histology Parameters in Broiler Breeder Roosters

Correlation of Plasma Lipids' Profile with Testicular Histology Parameters in Broiler Breeder Roosters

Improvements in semen quality, sperm fatty acids, and reproductive performance in aged Ross breeder roosters fed a diet supplemented with a moderate ratio of n-3: n-6 fatty acids.

The purpose of this study was to evaluate the effects of dietary n-3: n-6 fatty acid (FA) ratios and vitamin E (vitE) on the semen quality, FA composition, hormonal responses, and reproductive performance of aged roosters. Thirty-six Ross broiler breeder roosters were assigned to a 3 × 2 factorial design with 3 n-3: n-6 FA ratios (0.09, 0.16, and 0.23) based on the inclusion of 3 oil sources (canola, canola/fish, and fish) and 2 vitE levels (0 and 200mg/kg). During the 60 d of treatment, semen parameters, FAs composition of sperm, lipid peroxidation, and hormonal responses were monitored. Reproductive performance using artificial insemination was also evaluated at the end of experiment (on day 60). Results showed that the 0.16 and 0.23 dietary ratios increased docosahexaenoic acid and n-3 polyunsaturated FA and decreased docosatetraenoic acid and arachidonic acid in rooster sperm (P<0.05). The 0.16 dietary ratio supplemented with 200mg vitE improved total sperm motility (P<0.05) than the 0.09 and 0.23 ratios, both with and without vitE. Progressive motility, membrane functionality, and viability were significantly (P<0.05) improved in the 0.16 and 0.23 ratios supplemented with vitE. The highest concentration of testosterone was observed in the roosters fed a diet ratio of 0.16 (P<0.05). Compared with no supplementation of vitE, 200mg/kg vitE reduced the lipid peroxidation of rooster sperm (P<0.05). In the artificial insemination, the higher significant percentage of fertility rate (P=0.02) was observed in the 0.16 ratio group that was supplemented with vitE compared to other groups. It can be concluded that supplementation of aged roosters' diet with 0.16 ratio of n-3: n-6 can be a beneficial strategy for improvement of their fertility.

Lycopene-loaded nanoliposomes improve the performance of a modified Beltsville extender broiler breeder roosters

Antioxidants may ameliorate the effects of the freeze-thawing stress on cryopreserved spermatozoa. Lycopene is an effective antioxidant yet to be tested for rooster sperm cryopreservation and nanoliposomes, a technology recently applied to sperm cryopreservation, could improve conservation and antioxidant delivery to spermatozoa. Therefore, we evaluated the effect of 0.1, 0.2, and 0.3 mM lycopene and lycopene-loaded nanoliposomes (LnL) on the cryopreservation of rooster sperm in Beltsville extender. Post-thawing evaluation included sperm motility, membrane integrity, abnormal morphology, mitochondria activity, apoptotic status, malondialdehyde (MDA) and antioxidant activities: Glutathione peroxidase (GPx), superoxide dismutase (SOD) and total antioxidant capacity (TAC). Total and progressive motility, membrane integrity and mitochondria activity were higher with 0.2 mM lycopene and LnL (P < 0.05), compared to 0.1 and 0.3 mM (lycopene and LnL) and the control group. The 0.2 mM lycopene and LnL showed a lower percentage of apoptotic sperm and increased GPx activity and TAC when compared with the other treatments, and reduced MDA levels when compared to 0.3 mM (lycopene and LnL) and control. Supplementation did not significantly affect activities of SOD or the proportion of abnormal spermatozoa. A fertility trial showed that 0.2 mM lycopene increased the proportion of fertile and hatched eggs in comparison to the control, especially when using nanoliposomes. Therefore, the supplementation of the Beltsville extender with 0.2 mM lycopene could improve the quality of rooster spermatozoa after freeze-thawing, and the combination with nanoliposomes seems promising in order to improve the performance of existing approaches.

Reproductive performance of floored and cage housed broiler breeder roosters

Reproductive performance of floored and cage housed broiler breeder roosters

Comb, cloaca and feet scores and testis morphometry in male broiler breeders at two different ages

ABSTRACT In broiler breeder roosters, the weight of the testes is positively associated with daily sperm production and fertility. In birds, the testes are located in the coelomic cavity, not being accessible to reproductive evaluation as mammalian testes. The reproductive evaluation of roosters is based on phenotypic traits. Any changes on testes will be reflected on fertility levels. The aim of this paper was to evaluate the potential of association of phenotypic traits as body weight (BW), comb scores (COS), cloaca scores (CLS) and feet scores (FS) with testicular morphometric parameters in adult Cobb® Mx roosters in two ages (25 and 45 weeks of age). The low BW roosters had lower testes weight (TW), smaller seminiferous tubule diameter (STD) and lower comb and cloaca scores than the medium and high BW roosters (P≤0.05). Heavy roosters had the highest COS and bigger seminiferous epithelium height (SEH). There was no statistical difference between the BW categories in FS and volumetric proportion of seminiferous tubule (ST) and interstitial tissue (IT). Considering the age effect, roosters with 45 weeks of age had lower TW and ST than 25-week roosters. Positive, moderate and significant correlation was found between testes weight and phenotypic characteristics as BW, COS and CLS in 45week roosters. A positive, moderate and significant correlation was found between body weight and histologic testicular characteristics as STD and SHE in both evaluated ages. In conclusion, there is a regression in the testes weight with age and it is more intense in Cobb® Mx roosters with lower BW. Furthermore, it is concluded that the BW positively influences the testes weight and histological quality of the testes. COS and CLS can be used with moderate potential prediction to identify roosters with low testes weight at 45 weeks of age.

Association of the severity of tongue lesions in broiler chickens with the quality of corn in feed

Abstract: The objective of this work was to determine the correlation of the physical attributes of corn and the mycotoxins present in its grains with the severity of tongue lesions in broiler breeder roosters. The occurrence of the aflatoxin, vomitoxin, zearalenone, T-2 toxin, and fumonisin mycotoxins was detected in the corn grains used in the feed formulation for breeder chickens. The percentages of moisture and broken grains were positively correlated (Pearson’s correlation) with the presence of aflatoxin. Milder lesions (grade 1) are positively correlated with aflatoxin and negatively correlated with fumonisin, and the most severe lesions (grade 3) are positively correlated with vomitoxin, fumonisin, and T-2 toxin.

Effects of guanidinoacetic acid diet supplementation on semen quality and fertility of broiler breeder roosters

Decreased semen quality and fertility rate is a common feature in broiler breeder roosters. This decrease is associated with dysfunction of Sertoli cells and defective spermatogenesis. Guanidinoacetic acid (GAA), as a precursor of creatine, plays an important role in the proper functioning of Sertoli cells and energy metabolism in sperm. Twenty, 29-wk-old broiler breeder roosters (Ross 308) were randomly allotted to 4 treatment groups and fed diets supplemented with different levels of GAA, including 0 (GAA-0), 600 (GAA-600), 1200 (GAA-1200), and 1800 (GAA-1800) mg GAA/kg of diet for 26 successive weeks. During a 24-wk period, the seminal characteristics were weekly evaluated. At the end of experiment, sperm penetration and fertility rates were determined, using 68 artificially inseminated age-matched broiler breeder hens of the same strain (for 2 weeks). Semen concentration (P = 0.003), total sperm number (P = 0.005) and sperm forward motility (P = 0.01) were increased by GAA-1200 group. Also, sperm plasma membrane functionality was marginally affected (P = 0.06) in roosters received all levels of GAA. Sperm abnormality and plasma membrane integrity were not affected by dietary GAA. The highest number of sperm penetration holes was recorded for the GAA-1200 group (P = 0.08). Interestingly, fertility rate was increased by the feeding of all levels of GAA (P = 0.01). In conclusion, dietary GAA was associated with improvement in most of the rooster's seminal characteristics and fertility rate, suggesting a potential for using GAA to attenuate the age-related sub-fertility in commercial broiler breeder roosters.

Avaliação da suplementação antioxidante na dieta para galos de matrizes pesadas em idade avançada sobre parâmetros reprodutivos

RESUMO Objetivou-se avaliar os efeitos de antioxidantes suplementados às dietas de galos de matrizes pesadas em idade avançada sobre as características reprodutivas. Foram utilizados galos da linhagem Cobb com 47 semanas de idade. Estes foram distribuídos em quatros tratamentos, de acordo com a adição de antioxidante à dieta, sendo: A = grupo controle (sem suplementação antioxidante); B = suplementação de 9ppm de citranaxantina; C = suplementação de 6ppm de cantaxantina e D = 150ppm de vitamina E. Foram avaliadas as características seminais, tais como volume, vigor, motilidade e concentração, a composição de ácidos graxos do sêmen (saturados, insaturados, monoinsaturados, poli-insaturados, ômega 3, ômega 6 e ômega 9) e a correlação entre o peso dos testículos e o peso dos galos. Não foram observados efeitos das substâncias antioxidantes testadas sobre os parâmetros reprodutivos avaliados. Os antioxidantes avaliados não influenciam as respostas reprodutivas de machos reprodutores de matrizes pesadas em idade avançada.

Detecting reproductive system abnormalities of broiler breeder roosters at different ages.

The objective of this study was to detect the reasons of rooster's fertility decrease at 50weeks 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 50weeks). 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 50weeks of age. Therefore, the use of the laparoscopy as a way to detect the roosters with testicular atrophy before 50weeks of age and their removal from them flock could be useful as a diagnostic tool to prevent the birds' fertility loss.

Morphometric Documentation of a High Prevalence of Left Ventricular Dilated Cardiomyopathy in Both Clinically Normal and Cyanotic Mature Commercial Broiler Breeder Roosters with Comparisons to Market-Age Broilers.

Previous studies documented the common occurrence of transitory cyanosis and echocardiographic aortic insufficiency in mature commercial broiler breeder roosters. During further investigations, we observed a high prevalence of hearts exhibiting extensive dilation of the left ventricle chamber compatible with dilated left ventricular cardiomyopathy present in both cyanotic and normal subpopulations. We conducted quantitative studies focused on documentation of cardiac ventricle parameters by using simple gross morphometric methods performed on formalin-fixed hearts obtained from both clinically normal roosters and those exhibiting variable transitory cyanosis, echocardiographic aortic insufficiency, or both. A high prevalence of often dramatic left ventricular dilation reflected in enlarged left ventricular chamber areas and elevated left ventricle-to-total ventricle area ratios was morphometrically documented. However, no statistically significant differences in the occurrence of ventricular abnormalities were observed between normal and cyanotic roosters. Age-associated changes were also demonstrated by comparative morphometric studies on hearts from normal market-age broilers (average age of 7 wk) and those of mature roosters (average age of 42 wk). Elevation in both left and right ventricular weight-to-total heart weight ratios dramatically increased with aging. In addition, values (average ± SD) for the left ventricle chamber area-to-total ventricle area ratios increased from 3.2 ± 2.0% in broilers up to 10.0 ± 8.8% in roosters. None of the normal broilers studied demonstrated left ventricular volume ratios above 10%, whereas 33% of the roosters had left ventricular volume ratios above 10%, including 13% with ratios of 20% or higher. However, the left ventricle wall area-to-body weight ratios were much closer for the two age groups (0.85 ± 0.18 cm(2)/kg in broilers and 0.79 ± 0.13 cm(2)/kg in roosters). Also, the standard right ventricle-to-total ventricle weight ratio (RV/TV) went from 0.18 ± 0.04 in broilers to 0.25 ± 0.12 in roosters, whereas the left ventricle-to-total ventricle weight ratios were similar for the two age groups (0.74 ± 0.12 and 0.75 ± 0.08 in broilers and roosters, respectively). Our results for RV/TV in normal broilers were similar to the reported values for normal market-age broilers. In contrast, 36% of the roosters had RV/TV above values reported for broilers considered reflective of right ventricular hypertrophy due to pulmonary hypertension, whereas 4% had values above the reported threshold for broilers dying with ascites (ratios greater than 0.0249 and 0.299, respectively). However, ascites was not observed for any of the roosters. Although essentially all cardiac morphometric parameters demonstrated statistically significant correlations with the age-class group comparisons, significance could not be documented for comparisons between cardiomorphometrics and the subjective occurrences of transitory cyanosis or echocardiographic aortic insufficiency.

Role of the serotonergic axis in the reproductive failure associated with aging broiler breeder roosters

Reproductive failure associated with aging is a well-known phenomenon. However, the mechanism by which this failure occurs in broiler breeder roosters is still unclear. A previous study conducted in our laboratory, comparing young and aging broiler breeder roosters, demonstrated an elevation in hypothalamic vasoactive intestinal peptide (VIP) and pituitary prolactin (PRL) gene expression accompanied by a deterioration of gonadal axis function. This resulted in a decrease in semen-quality variables as roosters aged. The objective of this study was to examine the involvement of the serotonergic axis in the age-associated reproductive failure in broiler breeder roosters. Cobb roosters aged 64 wk were divided into 3 groups (n = 20 each): parachlorophenylalanine (PCPA) administration, active immunization against chicken VIP, and controls. At 69 wk of age, each group was divided into 2 equal subgroups: 1 received ovine PRL and the other served as controls. Weekly semen volume, concentration and motility, and plasma testosterone, estradiol, and PRL concentrations were examined. At the end of the experiment, roosters were euthanized, testes were weighed, and hypothalamus and pituitary were removed to assay the expression of genes encoding hypothalamic GnRH-I, pituitary FSH, pituitary LH, hypothalamic VIP, and pituitary PRL. Both PCPA administration and active immunization against chicken VIP significantly increased testis weight, semen volume, sperm concentration, ejaculation grade, plasma testosterone level, and GnRH-I, FSH and LH gene expression compared with controls (P ≤ 0.05). In addition, a decrease in plasma estradiol and PRL concentrations and VIP and PRL gene expression was observed in PCPA- and VIP-immunized birds compared with controls (P ≤ 0.05). Administration of PRL in all groups decreased gonadal axis function and semen-quality variables (P ≤ 0.05). Collectively, these results suggest that the increasing expression levels of the serotonergic axis in aging broiler breeder roosters inhibit proper gonadal function and reproductive performance. This article establishes for the first time the inhibitory role of serotonin on reproduction in aging roosters.

Escores de cloaca e de crista e morfometria testicular em galos de matriz pesada com 71 semanas de idade e três categorias de peso corporal

Em galos de matriz pesada, o peso dos testículos se associa positivamente com a produção diária de espermatozoides e com a fertilidade. Contudo, os testículos de aves se localizam na cavidade abdominal, não sendo acessíveis para exame andrológico como os testículos de mamíferos. A avaliação reprodutiva de galos de matriz pesada é subjetiva e se baseia em características como peso corporal (PC), qualidade de pés e pernas e morfologia de cloaca e crista. Estudos que validem o potencial de associação dessas características fenotípicas com parâmetros da morfometria testicular são raros, principalmente quando se consideram galos de matriz pesada manejados em lotes comerciais. Escores de cloaca e de crista e parâmetros da morfometria testicular foram avaliados em galos Cobb 500 Slow adultos das categorias de PC leve (&lt;4,300kg), médio (entre 4,300 e 5,250kg) e pesado (≥5,250kg). O coeficiente de variação para PC foi de 12%. Os galos da categoria de PC pesado apresentaram testículos mais pesados e maiores escores de cloaca e de crista do que os galos da categoria de PC leve. Não houve diferença estatística entre as categorias de PC, considerando-se índice gonadossomático, porcentagens de túbulo seminífero e de tecido intersticial, diâmetro de túbulo seminífero e altura de epitélio seminífero. Correlação positiva, moderada e significativa foi observada entre peso de testículo e características de PC, escores de cloaca e de crista, diâmetro de túbulo seminífero e altura de epitélio seminífero. Um dos seis galos da categoria de PC leve avaliados quanto à histologia de testículo apresentou atrofia testicular. Em galos Cobb 500 Slow, conclui-se que o PC influencia o peso e a qualidade histológica de testículos e que os escores de cloaca e de crista podem ser utilizados com potencial moderado de predição para identificar galos com baixo peso de testículos.

Reproductive performance, semen quality, and fatty acid profile of spermatozoa in senescent broiler breeder roosters as enhanced by the long-term feeding of dried apple pomace

Avian spermatozoa are characteristically high in polyunsaturated fatty acids which predispose them to lipoperoxidation, thereby diminishing their fertility. As a by-product, well-known for antioxidative properties, dried apple pomace (AP) was fed to aging Ross 308 breeder roosters (n=80) at the dietary inclusion levels of 0 (AP0), 10 (AP10), 20 (AP20), or 25 (AP25) percent for 14 consecutive weeks. Seminal traits were studied every other week. At the end of the trial, sperm fatty acids profile, seminal plasma total antioxidant capacity (TAC), fertility, hatchability, and hatchling quality were evaluated, using 240 artificially-inseminated young hens. Dietary AP increased sperm motility and livability and decreased the seminal content of thiobarbituric acid reactive species. Dietary treatment and age interacted to positively affect sperm concentration and sperm membrane integrity. Feeding AP was associated with an increase in C20:4(n-6), C22:4(n-6), and total unsaturated fatty acids percentages. Birds in the AP25 and AP20 treatment groups respectively showed 6 and 7% increases in fertility rate. Interestingly, a higher hatchability rate was found for AP20 group, associated with a higher number of sperm penetration holes in the perivitelline membrane and a lower rate of early embryonic mortality. However, hatchling quality was not affected by dietary AP. Overall, these data suggest that AP could remarkably improve several sperm characteristics, seminal TAC, fertility, and hatchability rate in aging breeder roosters. These improvements were also associated with a higher content of total unsaturated FA in the sperm plasma membrane. Future studies are needed to disclose the causal mechanisms involved.

Age-related changes in gonadal and serotonergic axes of broiler breeder roosters

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.

Relationships Between Fertility and Some Parameters in Male Broiler Breeders (Body and Testicular Weight, Histology and Immunohistochemistry of Testes, Spermatogenesis and Hormonal Levels)

In a farm of grandparent broiler breeder chickens, we followed the development of 350 roosters from 6 to 55 weeks of age. Data collected and evaluated from these males included body weight, testicular weight, histologic and immunohistochemistry studies of the testes, hormone levels (testosterone, estradiol and corticosterone) and sperm production. The objective was to understand the factors that affect or influence hatch loss that is commonly observed after 45 weeks of age in breeder flocksare often correlated to broiler breeder male chickens. The results of this study showed that in conjunction with the weight of the rooster, the testicle weight increases quickly after the rooster receives light stimulation. At an older age, the study showed that there is a process of testicular shrinkage, and the same effect is seen in sperm production and testosterone levels in broiler breeder roosters. From the histology evaluation, we defined 5 histologic phases that illustrate the evolution of the testicular tissue: perinatal, infantile, puberty, adult and senile. We observed that the adult males with a body weight <3800 g were infertile or had subfertile levels and also had low levels of testosterone and high levels of corticosterone. In contrast, the heaviest males showed correct testicular vitality, high levels of testosterone and low levels of corticosterone. However, the roosters that had acquired this high body weight were also at risk of having less complete copulations because of their physical mass. The loss of uniformity of the males and the appearance of hierarchies within the flock accompany a decline in the percentages of hatches as a consequence of the poor confirmation of the males for copulation or the restriction to the access to the females. Results of this study show that the decrease in fertility from 45 weeks of age has been associated with a decline in testicular weight, sperm production and the testosterone levels in animals with a sub-par weight. Likewise, decreasing hatch in older flocks may also result from a loss of conformation, and the lack of complete copulations is possible because of animals that are grossly overweight.

The effect of dietary n-6:n-3 ratio and sex on broiler breeder immunity

A study was conducted with male and female adult broiler breeders to determine the effect of feeding a fish oil supplement on selected immune activities. The fish oil was added to the diet such that the n-6:n-3 ratios could meet certain levels. Four hundred Ross 308 broiler breeder hens and 48 Ross 308 broiler breeder roosters at 30 wk of age were randomly assigned to diets containing 3.5% fat with n-6:n-3 ratios of 4, 6, 8, and 16. As a measure of cell-mediated immunity, thickness of the toe web was measured at 4, 8, 24, and 48 h after injection of phytohemagglutinin-P (PHA-P) at 32 wk of age. Total antibodies were quantified 6 and 9 d after the injection of SRBC at 33 wk of age. Blood lymphocyte proliferation was assayed after in vitro stimulation with PHA-P at 34 wk of age. The fatty acid profile of the spleen was determined in roosters. The effects of dietary n-6:n-3 ratios on total antibodies and in vitro lymphocyte proliferation were not significant (P > 0.05). However, the birds fed diets containing an n-6:n-3 ratio of 8 showed the greatest toe web thickness (P < 0.05). Total antibodies in hens at 9 d after SRBC injection were significantly greater than those of roosters. Conversely, toe web thickness in roosters was greater than that of hens (P < 0.05). Although the increase in the dietary n-6:n-3 ratio of polyunsaturated fatty acids significantly decreased the concentrations of eicosapentaenoic acid, docosahexaenoic acid, total n-3 (P < 0.05), linoleic acid, arachidonic acid, and total n-6, the n-6:n-3 fatty acid ratios of the entire spleen were significantly increased (P < 0.05). Results indicated that under the conditions of this study, the n-6:n-3 ratios seemed to influence the toe web response to PHA-P, but not the antibody response or the cell proliferation response in vitro.

Association of Enterococcus cecorum with vertebral osteomyelitis and spondylolisthesis in broiler parent chicks

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.

Effect of ascorbic acid on chicken semen quality during liquid storage

The aim of this study was to evaluate the in vitro effects of ascorbic acid on Ross-308 chicken sperm quality. The semen was collected from eight teen Ross-308 broiler breeder roosters and mixed together. The mixed semen was diluted with modified Ringer’s solution and supplemented with five treatment levels (0%, 0.5%, 1%, 2%, and 3%) of ascorbic acid (w/v). Treatments were evaluated for sperm motility, viability, and morphological defect rates at 0, 3, 6, 10, and 24 h after storage at 4°C. At 0, 3, and 6 of storage, no significant differences were observed between treatments with ascorbic acid and controls for all spermatozoa quality parameters. At 10 h, sperm viability in treatment added with 1% ascorbic acid was significantly higher than control and other treatments. In this time, there were not significant differences among treatments with 0%, 0.5%, 2%, and 3% ascorbic acid. At 24 h, sperm motility in treatment with 1% ascorbic acid and sperm viability in treatments contain 1% and 2% ascorbic acid were higher than controls and other treatments. In this period, morphological defect percent of spermatozoa in treatment with 1% ascorbic acid was significantly lower than control and other treatment groups. Also, at 24 h, sperm morphological defect percent in treatment added with 3% ascorbic acid was significantly higher than that in control and other treatments.

Sel-Plex® Improves Spermatozoa Morphology in Broiler Breeder Males

Sodium Selenite (SEL) has been the traditional source of Selenium (Se) in poultry diets, but SelPlex® (SP, a source of organic selenium in yeast protein, Alltech Inc.) has become widely used in several countries signaling its importance as a replacement for SEL. SP is equivalent or even superior to SEL in terms of gut absorption, performance, induction of whole body feathering and tissue retention. Therefore, it was important to extend our understanding of the influence of selenium on performance characteristics of poultry by comparing the influence of SEL or SP in broiler breeder roosters. In the first part of this investigation, 14-week-old roosters were fed diets that contained SEL, SP, or no supplemental selenium (deficient). Selenium-supplemented roosters produced semen at 19 weeks of age while selenium-deficient roosters did not produce semen until 26 weeks of age. Semen quality, as indicated by spermatozoal morphology, was best for SP-fed roosters and SEL-fed roosters produced semen with a quality that was intermediate between SP-fed and selenium-deficient rooster semen quality. In the second part of this investigation, adult roosters in a commercial setting were fed SEL at 0.3 ppm Se/kg of diet until they were 19 weeks of age and then half of the males on each of two farms were fed SP at 0.3 ppm Se/kg of diet. At 32 and 42 weeks of age, semen samples were evaluated via microscopy for quality based on spermatozoal morphology and spectrophotometric analysis to determine a sperm quality index, consisting of a composite determined by sperm motility and sperm density in the semen sample. The results from the laboratory trial and the field trial suggest that SP is superior to SEL as a source of selenium for broiler breeder males. This conclusion was further supported by histological evaluation of testicular tissues from roosters fed either no supplemental selenium, SP or SEL.