An evaluation of the effect of altering nutrition and nutritional strategies in early lactation on reproductive performance and estrous behavior of high-yielding Holstein-Friesian dairy cows

Reproductive performance in the high-yielding dairy cow has severely decreased in the last 40 yr. The aim of this study was to compare the effectiveness of 4 nutritional strategies in improving the reproductive performance of high-yielding dairy cows. It was hypothesized that offering cows a high-starch ration in early lactation would enhance the onset of luteal activity, and that decreasing the severity of negative energy balance in the early postcalving period would improve reproductive parameters. Nutritional regimens aimed at improving fertility were applied to 96 Holstein-Friesian dairy animals. Upon calving, animals were allocated in a balanced manner to one of 4 dietary treatments. Primiparous animals were balanced according to live weight, body condition score and calving date. Multiparous animals were balanced according to parity, previous lactation milk yield, liveweight, body condition score and calving date. Treatment 1 was based on an industry best practice diet (control) to contain 170 g of crude protein/kg of dry matter. Treatment 2 was an individual cow feeding strategy, whereby the energy balance (EB) of individual animals was managed so as to achieve a predetermined target daily EB profile (+/- 10 MJ/d). Treatment 3 was a high-starch/high-fat combination treatment, whereby an insulinogenic (high-starch) diet was offered in early lactation to encourage cyclicity and followed by a lipogenic (low-starch, high-fat) diet to promote embryo development. Treatment 4 was a low-protein diet, containing 140 g of crude protein/kg of dry matter, supplemented with protected methionine at an inclusion level of 40 g per animal per day. The nutritional strategies implemented in this study had no statistically significant effects on cow fertility measures, which included the onset of luteal activity, conception rate, in-calf rate, and the incidence of atypical cycles. The individual cow feeding strategy improved EB in early lactation but had no benefit on conception rate to first insemination. However, conception rate to second insemination, 100-d pregnancy rate (from the commencement of breeding), and overall pregnancy rate tended to be higher in this group. The high-starch/high-fat treatment tended to decrease the proportion of delayed ovulations and increase the proportion of animals cycling by d 50 postcalving. Animals that failed to conceive to first insemination had a significantly longer luteal phase in the first cycle postpartum and a longer inter-ovulatory interval in the second cycle postpartum. With regards to estrous behavior, results indicate that as the size of the sexually active group increased, the intensity of estrus and the expression of mounting or attempting to mount another cow also increased. Furthermore, cows that became pregnant displayed more intense estrous behavior than cows that failed to become pregnant.

Truth at 24 frames a second? A working dialogue between a film-maker and a historical consultant about the making of The Enigma of Frank Ryan

We employ a practice-based methodology based on a ‘live’ film project to explore the different ways that film-makers and historians narrate the past. Through a case-study of the production and exhibition of a drama-documentary feature-film, The Enigma of Frank Ryan, on which both authors (film-maker Bell and historian McGarry) worked respectively as director and historical consultant, we explore a range of critical issues arising from our collaboration. Through a dialogue between a director and a historian, a model of good practice between historians and film-makers emerges.

O Corpo Masculino Queer e Digital na Arte Contemporânea: Ryan Trecartin e Jacolby Satterwhite

Esta dissertação pretende analisar as práticas de dois artistas contemporâneos, Ryan Trecartin e Jacolby Satterwhite, nomeadamente a nível do modo como trabalham a intersecção do vídeo digital e da performance como forma de manifestação de corporalizações queer através do corpo masculino. Mais concretamente, interessa-nos focar processos de “queerificação” e de produção de corpos que emergem intrinsecamente pelo médium digital, e que exploram as possibilidades transformativas do médium tanto a nível de representação, criação e mutação de formas, como a nível comunicacional e de possibilidades de subjectivação e corporalizações múltiplas. Para tal, partimos dos dois campos teóricos que se mostraram mais pertinentes relativamente aos processos artísticos em análise, nomeadamente: a teoria queer pelo modo como definiu o carácter performativo das normas de género e as categorizações identitárias sexuais como suporte da heteronormatividade, identificando estratégias para a sua re-significação; e o pensamento sobre a relação do corpo com o médium digital, pelo modo como delineou processos de corporalização através da tecnologia digital. A análise dos processos artísticos de Ryan Trecartin e Jacolby Satterwhite demonstra como a arte contemporânea é um território fértil não apenas para a exposição de matrizes normativas de opressão, mas também para a criação de mundos radicalmente queer em que, fazendo uso do potencial transformativo do médium digital, se manifestam realidades e corpos onde a normatividade é totalmente implodida.

Anvers, Pat Ryan, gagnant du lancer du marteau [Jeux olympiques, le 18/8/20] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60648

Professor Fred Smoller, Child Study Center, Chapman College, Orange, California

Professor Fred Smoller, Child Study Center, Chapman College, Orange, California, June, 1990.