Comparison of four strategies of ram management in a semen collection centre

Thirty Merino rams were used to determine the effect of four management systems of rams on semen quality during the anoestrous season. Animals were divided into four groups: Artificial-Photoperiod group (AP; n = 8), which were isolated from females and exposed to artificial long days (16 hr/d) from 1 Feb to 15 Mar; Natural-Photoperiod (NP; n = 8), isolated from females and exposed to the natural photoperiod throughout the experiment; Oestrous-Ewe group (EE; n = 7), housed in a pen adjacent to another pen that housed three ewes in oestrus, and Anestric-Ewe group (AE; n = 7), housed adjacent to another pen that housed three ovariectomized ewes. From 20 Mar to the end of May (10 weeks), semen samples were collected weekly, and blood samples were collected to determine plasma testosterone concentrations. Mean plasma testosterone concentrations, ejaculate volume and reaction time were not affected either by treatment or week. There was a significant effect (p < .01) of ram treatment on sperm concentration, and both TM y PM, and their interaction, were significantly affected by group and week (p < .001). Rams exposed to ewes in oestrus presented the largest sperm concentration (p < .05) compared with the other three groups, although they had the lowest total and progressive motilities (p < .01). In conclusion, management strategy in spring affects semen quality of rams, with the presence of ewes in oestrus being the best plan to increase sperm concentration

Can the understory affect the Hymenoptera parasitoids in a Eucalyptus plantation?

The understory in forest plantations can increase richness and diversity of natural enemies due to greater plant species richness. The objective of this study was to test the hypothesis that the presence of the understory and climatic season in the region (wet or dry) can increase the richness and abundance of Hymenoptera parasitoids in Eucalyptus plantations, in the municipality of Belo Oriente, Minas Gerais State, Brazil. In each eucalyptus cultivation (five areas of cultivation) ten Malaise traps were installed, five with the understory and five without it. A total of 9,639 individuals from 30 families of the Hymenoptera parasitoids were collected, with Mymaridae, Scelionidae, Encyrtidae and Braconidae being the most collected ones with 4,934, 1,212, 619 and 612 individuals, respectively. The eucalyptus stands with and without the understory showed percentage of individuals 45.65% and 54.35% collected, respectively. The understory did not represent a positive effect on the overall abundance of the individuals Hymenoptera in the E. grandis stands, but rather exerted a positive effect on the specific families of the parasitoids of this order