14 research outputs found
Development of sexual behaviour in commercially-housed broiler breeders after mixing
1. It has been reported that broiler breeder males behave aggressively towards females during mating. However, the cause of this aggressive sexual behaviour is not yet clear. In this experiment we studied the development of the sexual behaviour in male and female broiler breeders from mixing (20 weeks of age) until complete development of the behaviour (28 weeks of age) to formulate hypotheses on the causes of the aggressive mating behaviour. 2. Behaviour was observed on 8 farms with commercially-housed Ross 308 broiler breeder parent stock (males and females) at 20, 22, 24, 26 and 28 weeks of age, either observed by direct observations at 6 different locations in two units per farm, or recorded on video tape in one unit per farm for more detailed observations. 3. Broiler breeder males behaved aggressively towards females both during and outside the mating context. Some elements of courtship behaviour were not observed. Upon male approach hens either did not respond or they ran away. Males frequently used forced behaviour before mating (pushing hens into a crouch position). The majority of the matings did not succeed (no copulation, due to frequent escape of hens) and was forced (no voluntary crouching of the hen). Rough male behaviour did not decrease, neither did hens show habituation or a more ¿normal¿ response over the 8 weeks observation period. 4. We conclude that both male and female sexual behaviour of commercially-housed broiler breeders seem to be incomplete and may be indicative of poor welfare and stress, especially in the hens. We hypothesise that factors like separate rearing (common practice under commercial conditions), large group sizes and stocking density may play an important role in the development and performance of sexual behaviour and should be further studie
Ruwe macho's in de stal. Paargedrag bij vleeskuikenouderdieren
Bij de vleeskuikenouderdieren blijken hanen weinig zachtzinnig om te springen met de hennen, blijkt uit een praktijkinventarisatie in Nederlandse stallen. Dit kan problemen op gaan leveren, nu ingrepen bij hanen om veer- en huidbeschadigingen bij hennen te voorkomen, niet langer zijn toegestaa
Goede moed na ronde 1
In de eerste ronde met de Quality Time-stal heeft het iets betere paargedrag zich (nog) niet vertaald in een betere bevruchting. Aanpassingen moeten er in ronde 2 voor zorgen dat dit wel gebeurt
Cutis laxa, fat pads and retinopathy due to ALDH18A1 mutation and review of the literature
Contains fulltext :
137727.pdf (publisher's version ) (Closed access)Autosomal recessive cutis laxa (ARCL) is a connective tissue disorder characterized by wrinkled, inelastic skin, frequently associated with a neurologic involvement and multisystem disease. Next generation sequencing was performed in genetically unsolved patients with progeroid features, neurological and eye involvement to assess the underlying etiology. We describe an 6 month old child, diagnosed with a novel, homozygous nonsense mutation c.2339T>C in exon 18 of the ALDH18A1 gene, and reviewed all reported P5CS patients. So far 10 patients were described with mutations in ALDH18A1. Features of our patient that have been described in literature included cutis laxa on hands and feet, visible veins on thorax and abdomen, joint laxity, failure to thrive, short stature, microcephaly, and severe developmental and speech delay. Furthermore, abnormal fat distribution, retinal abnormalities, undescended testis, and retinitis pigmentosa have never been described in ALDH18A1. Some features described as unique in ALDH18A1 have been observed in PYCR1 patients, thus suggesting that the phenotypic overlap is higher than previously shown. In conclusion, the clinical phenotype caused by ALDH18A1 mutations is diverse, with variable degree of progeria in children, but always in association with neurologic disease. We suggest genetic testing for possible ALDH18A1 mutations in all patients with progeroid features, like wrinkled or parchment-like skin, abnormal growth, especially with central nervous system involvement and microcephaly