Combined effect of permeant and non-permeant cryoprotectants on the quality of frozen/thawed chicken sperm.

The aim of this study was to assess the combined effect of dimethylacetamide (DMA) and two non-permeating cryoprotective agents, trehalose and sucrose, on the quality of post-thaw chicken semen. Adult Lohmann roosters (n = 27) were used. Semen was processed according to the following treatments: Lake pre-freezing extender +6% DMA (LPF, control treatment), LPF + 0.1 M trehalose (LPF-T treatment), LPF + 0.1 M sucrose (LPF-S treatment) and LPF + 0.1 M trehalose + 0.1 M sucrose (LPF-TS treatment). Semen was loaded into straws and frozen in nitrogen vapour. Sperm quality (viability, mobility and kinetic parameters) was assessed immediately after thawing (T0) and at 5 (T5), 10 (T10) and 15 min (T15) thereafter. The different cryodiluent combinations significantly affected the kinetic parameters. The presence of trehalose, alone or with sucrose, combined with DMA improved the quality of motion in cryopreserved sperm in comparison to DMA alone (LPF) and DMA with sucrose (LPF-S). In particular, the highest values in linearity (LIN) and wobble (WOB) were measured in the treatment LPF-T. The treatments significantly affected the recovery rate of progressive motile sperm that presented the best value soon after thawing in the LPF-T treatment; moreover, the presence of trehalose, alone (LPF-T) or with sucrose (LPF-TS), significantly improved the recovery rate of progressive motile sperm also at T5 and T10 compared to LPF and LPF-S. The present results show a positive synergic action of DMA and trehalose on motile function of thawed chicken sperm.

Overview of Native Chicken Breeds in Italy: Small Scale Production and Marketing.

The intensive use of high-performing strains in poultry production has led to the extinction of several autochthonous chicken breeds and, consequently, loss of genetic variability. Interest in saving biodiversity is growing rapidly and has become a major objective worldwide. The aim of this study was to shed light on the production trends of native Italian poultry breeds and the related market. A questionnaire, which asked about the production cycles, the number of animals and table eggs produced per year and their retail prices was completed by 121 breeders across Italy. The surveyed breeders were divided into two categories: breeders conducting an agrozootechnical farm, referred to as 'farmers' (F); and breeders keeping chickens as backyard poultry, referred to as 'fancy breeders' (FB). Analysis of the data acquired indicated that animals were mainly slaughtered between 6 and 12 months of age, with F processing more animals per year. The same production trend was observed for table eggs. The recorded retail prices of native chicken products were higher than those for conventional products, but similar to those reported for valuable niche poultry products, such as the Poulet de Bresse in France and organic eggs. Knowledge about these highly valuable markets should be used to encourage the use of local breeds in alternative poultry farming and help protect biodiversity.

Effect of N-Methylacetamide Concentration and Thawing Rate on Chicken Sperm Quality after Cryopreservation.

In seeking alternative cryoprotectants to glycerol for a reference chicken semen freezing procedure, the aim of the present study was to compare the effect of two concentrations of N-Methylacetamide (MA) and two thawing rates on the quality of frozen-thawed semen. Semen samples were diluted in Lake pre-freezing extender, including 0.1 M trehalose in presence of 6% or 9% MA, loaded into straws, frozen in nitrogen vapors, and stored in liquid nitrogen. The following thawing treatments were used: 5 °C for 100 s and 38 °C for 30 s. Sperm quality (cell membrane integrity, motility and kinetic parameters) was assessed before and after cryopreservation. The decrease of MA concentration from 9 to 6% improved sperm quality after freezing/thawing and this effect was dependent on thawing temperature. Decreasing the MA concentration from 9 to 6% improved the proportion of undamaged membrane, motile, and progressive motile sperm recovered after thawing at 5 °C for 100 s; in contrast, no effect of the MA concentration was observed thawing at 38 °C for 30 s. Therefore, the treatment with 6% MA and thawing at 5 °C for 100 s has given the best cryoprotective action. These results contribute to improve the efficacy of the current chicken semen cryopreservation procedures.

Data on the positive synergic action of dimethylacetamide and trehalose on quality of cryopreserved chicken sperm.

This data article contains supporting information regarding the research article entitled "Combined effect of permeant and non-permeant cryoprotectants on the quality of frozen/thawed chicken sperm"(Mosca et. al., 2016) [1]. The combined effect of the permeant cryoprotectants agent dimethylacetamide and the non-permeant cryoprotectants agent trehalose on the quality of frozen-thawed chicken semen was assessed. In particular, the quantitative dimethylacetamide/trehalose ratio was investigated freezing semen samples according to the following treatments: trehalose 0.1 M+0% dimethylacetamide (DMA-0), trehalose 0.1 M+3% dimethylacetamide (DMA-3), trehalose 0.1 M+6% dimethylacetamide (DMA-6).