Effects of in ovo vaccination time on broiler performance parameters under field conditions.

Hatchery performance is often evaluated based on descriptors such as hatchability, 7-d mortality, and cost. In addition to these descriptors, it is useful to include in this analysis aspects of chick quality through post-hatch performance. Realizing the bird's complete genetic potential necessitates meeting various criteria, with effective support for the chick's immune system being among the pivotal factors.

Successful xenotransplantation of testicular cells following fractionated chemotherapy of recipient birds.

An essential step in the success of germ cell transplantation is the preparation of the recipient's testicular environment to increase the availability of stem cell niches. However, most methods for this purpose in birds face serious limitations such as partial germ cell depletion, high toxicity and mortality, or the need to use expensive technologies. Here, we validated a simple and practical technique of transferring quail testicular cells into chicken testes depleted of endogenous spermatozoa by fractioned chemotherapy (20 mg/kg/week busulfan for 5 weeks).

Kinetic vitrification: concepts and perspectives in animal sperm cryopreservation.

Sperm cryopreservation is an important tool for genetic diversity management programs and the conservation of endangered breeds and species. The most widely used method of sperm conservation is slow freezing, however, during the process, sperm cells suffer from cryoinjury, which reduces their viability and fertility rates. One of the alternatives to slow freezing is vitrification, that consist on rapid freezing, in which viable cells undergo glass-like solidification.

Ecological drivers of breeding periodicity in four forest neotropical eagles.

We explore the potential factors that affect clutch initiation in four Neotropical large raptors (Harpy eagle-HE, Crested eagle-CE, Ornate hawk-eagle-OHE, and Black hawk-eagle-BHE) by analyzing 414 clutch events mostly obtained from captive individuals. Differences in how clutch initiation is associated with changes in photoperiod were found between HE and both hawk-eagles, and between CE and BHE. Changes in temperature at the time of clutch initiation only differed between HE and OHE, whereas changes in precipitation varied between BHE and all other species.

Ejaculate characteristics over seasons in five species of lancehead pitvipers (Bothrops spp) kept in captivity.

Due to their major medical importance in Latin America, lancehead pitvipers are frequently kept and bred in captivity for venom extraction to the production of antivenom serums. Nevertheless, despite the great contribution given to captive breeding, much of the knowledge of Bothrops' reproductive biology derived from sporadic and insufficient data provided by zoological collections. Thus, we aimed to investigate seasonal changes in gonadosomatic index (GSI) and seminal parameters (e.

Assessing different liquid-storage temperatures for rooster spermatozoa.

Although liquid-storage is extensively used in poultry, there are still questions on how sperm physiology is affected and to what extent sperm functions are disrupted by storage temperature and time. There, therefore, was investigation of storage temperature and durations on multiple semen variables. The storage at 37 °C was the most damaging, affecting values for several variables within 4 h of storage, whereas most differences occurred between 5 and 25 °C after 8 h.

Short-term cold storage of seminal samples of the golden lancehead pitviper (Bothrops insularis).

Assisted reproductive technologies such as cooling, freezing, and artificial insemination are essential in conserving genetic diversity of critically endangered reptiles like the golden lancehead pitviper (Bothrops insularis). Therefore, we examined viability of semen samples from captive golden lanceheads diluted in coconut-water based extender over a 48-h period of cooling (5°C). Semen evaluations were performed immediately after the dilution and at 6, 24, and 48 h, using computer-assisted sperm analysis and stains to assess plasma membrane and acrosomal status.

Fecal sex steroids and reproductive behaviors in harpy eagles (Harpia harpyja).

Aiming to improve our reproductive knowledge of large birds of prey, behavioral data and fecal steroids were assessed in captive pairs of Harpy eagles, a keystone species that is monogamous and resides in the Neotropics year-round. Adult individuals exhibited different reproductive outcomes and a breeding season extending beyond summer solstice (5-9 months) suggests that harpy eagles may not be absolutely photorefractory. Comparisons among breeding stages in males revealed that mean androgen levels in courtship were higher than in copulation and incubation, but no differences were detected in fecal progestagens or estrogens.

Seasonal effects on testes size and sustained semen quality in captive golden-headed lion tamarins, Leontopithecus chrysomelas.

The golden-headed lion tamarin (Leontopithecus chrysomelas) is an endangered primate that, according to timing of births, there seems to have seasonal reproductive patterns in captive populations inhabiting the Southern Hemisphere. The extent to which male tamarins have circannual cyclic fluctuations in testicular functions, however, remains unknown. Changes in testis size and seminal variables, therefore, were evaluated during the rainy and dry seasons of the year in seven males.

Assessment of different sperm functional tests in golden-headed lion tamarins (Leontopithecus chrysomelas).

The golden-headed lion tamarin (Leontopithecus chrysomelas) is an endangered species endemic to Brazil's Atlantic Forest, a shrinking biodiversity hotspot. As in other Neotropical primates, its semen characteristics and freezability are poorly studied. Hence, reproductive technologies for callitrichids would greatly benefit from reliable methods of semen analysis.

Immunolocalisation and expression of oxytocin receptors and sex hormone-binding globulin in the testis and epididymis of dogs: correlation with sperm function.

The aim of this study was to confirm gene and protein expression of oxytocin receptor (OTR) and sex hormone-binding globulin (SHBG) in the testis and epididymis of dogs, correlating these data with sperm quality and production and testosterone concentrations. Positive correlations were found between OTR and SHBG expression in both the testis and epididymis. Testicular OTR expression was positively associated with plasma membrane and acrosome integrity in canine spermatozoa, whereas SHBG expression in the testis was positively correlated with various sperm characteristics, such as sperm concentration, total and progressive motility, plasma membrane integrity and acrosome integrity.

Gonadal pathogenicity of an infectious bronchitis virus strain from the Massachusetts genotype.

An outbreak of infectious bronchitis caused by the IBVPR03 strain of the Massachusetts genotype affected H-120 vaccinated laying hens in South Brazil. We investigated the cross protection of the vaccine by assessing the traqueal ciliostasis, virus recovery, and histopathological changes typically observed in the respiratory tract. Although the IBVPR03 strain is S1-genotyped as Massachusetts with a high genomic similarity to the H-120 vaccine strains, surprisingly, we found no tropism or pathogenicity to the trachea in birds infected with this strain.

Semen collection by electro-stimulation in a variety of bird orders.

It is unquestinable that artificial insemination (AI) offers many benefits to avian conservation programs, but a serious impediment towards implementing AI for wild species is the development of effective techniques to consistently collect good quality ejaculates. Thus, we aimed to examine the success rate of electro-stimulation (ES) in collecting semen from 49 unconditioned males from orders Piciformes, Strigiformes, Accipitriformes, Cathartiformes, Galiformes, Anseriformes and Psittaciformes at different times of the year. Sixty out of 299 ES attempts provided ejaculates with sperm, but collection success rates varied widely (0-50%) depending on the species.

Carnosine as malondialdehyde scavenger in stallion seminal plasma and its role in sperm function and oxidative status.

Semen biotechniques may impair sperm quality due to excessive production of reactive oxygen species (ROS). Additionally, products of the oxidative reaction, especially involving lipids (e.g.

Effect of simple and low-cost enrichment items on behavioral, clinical, and productive variables of caged laying hens.

Housing layers in battery cages is a practice still used by many countries but it has been criticized because of its influence on behavioral repertoire of birds. We investigated whether simple and affordable enrichment devices alone impact behavior, foot condition and performance of laying hens housed in conventional cages. Hens were divided into plain cages (CON), cages with perches (PER), and cages with tassels and scratch-pads (ENR), and parameters were evaluated before and after enrichment placement.

Urofecal steroid profiles of captive Blue-fronted parrots (Amazona aestiva) with different reproductive outcomes.

Despite Psitaciformes (parrots) being the third largest nonpasserine order (398 species), it currently ranks second in number of threatened species (28%) according to the Internatinal Union for Conservation of Nature (IUCN) criteria. Since most of the literature concerning reproductive endocrinology in avian species derives from domestic and song birds, it is puzzling that advances in reproductive science for the Psitaciformes order lags far behind, in spite of the growing threats against them. In order to expand our knowledge of Neotropical parrots (Psittacidae), we examined annual changes in urofecal sex steroid metabolites of Blue-fronted amazon pairs (Amazona aestiva) exhibiting successful (nestlings) and unsuccessful breeding (infertile or no eggs).

Validation of simple and cost-effective stains to assess acrosomal status, DNA damage and mitochondrial activity in rooster spermatozoa.

Several methods have been developed to evaluate spermatozoa function in birds but many of these are sometimes complicated, costly and not applicable to field studies (i.e., performed within poultry breeding facilities).

Impact of induced levels of specific free radicals and malondialdehyde on chicken semen quality and fertility.

Over the past decades, scientists endeavored to comprehend oxidative stress in poultry spermatozoa and its relationship with fertilizing ability, lipid peroxidation (LPO), free-radical scavenging systems, and antioxidant therapy. Although considerable progress has been made, further improvement is needed in understanding how specific reactive oxygen species (ROS) and malondialdehyde (MDA, a toxic byproduct of LPO) disrupt organelles in avian spermatozoon. Hence, this study examined functional changes in chicken spermatozoa after incubation with different ROS, and their implications for the fertility.

Conservation of avian germplasm by xenogeneic transplantation of spermatogonia from sexually mature donors.

Approximately 12.5% of all 9,920 extant bird species in the world are threatened with extinction, and yet conservation efforts through natural breeding of captive species continue to encounter difficulties. However, sperm cryopreservation and artificial insemination offer potential benefits over natural breeding, but their applicability is still limited in nondomestic species.

RAD51 plays a crucial role in halting cell death program induced by ionizing radiation in bovine oocytes.

Reproductive health of humans and animals exposed to daily irradiants from solar/cosmic particles remains largely understudied. We evaluated the sensitivities of bovine and mouse oocytes to bombardment by krypton-78 (1 Gy) or ultraviolet B (UV-B; 100 microjoules). Mouse oocytes responded to irradiation by undergoing massive activation of caspases, rapid loss of energy without cytochrome-c release, and subsequent necrotic death.

Chemotherapy-induced late transgenerational effects in mice.

To our knowledge, there is no report on long-term reproductive and developmental side effects in the offspring of mothers treated with a widely used chemotherapeutic drug such as doxorubicin (DXR), and neither is there information on transmission of any detrimental effects to several filial generations. Therefore, the purpose of the present paper was to examine the long-term effects of a single intraperitoneal injection of DXR on the reproductive and behavioral performance of adult female mice and their progeny. C57BL/6 female mice (generation zero; G0) were treated with either a single intraperitoneal injection of DXR (G0-DXR) or saline (G0-CON).