Comparative study on milt quality features of different finfish species

The aim of this research was to study the main sperm characteristics of three different finfish species. Twenty-one gilt- head sea bream (Sparus aurata), 20 brown trout (Salmo trutta, morpha fario) and 15 rainbow trout (Oncorhynchus mykiss) male broodstocks, farmed under optimal conditions for each species and fed standard diets for broodstocks, were manually stripped. Brown trout yielded small amounts of sperm (4.5 vs18.13 ml) that were very concentrated (≅8.5 x 109 vs 1.24 x 109 Szoa/ml) with respect to the other species. The duration of spermatozoan motility for gilthead sea bream sperm was significantly longer (almost 50 min), in comparison to the one-minute motility of Salmonids. Single fatty acids of brown trout sperm were higher than in the other two species for almost all detected fatty acids. In partic- ular, eicosapentaenoic acid (EPA) was at least three times more concentrated in brown trout than in rainbow trout or gilt- head sea bream sperm (1238.3 µg/g vs305.6 and 333.3 µg/g, respectively; P < 0.01). Saturated, polyunsaturated and total unsaturated fatty acid classes were significantly higher in brown trout sperm than in the other two species - almost double with respect to gilthead sea bream sperm and more than double in comparison to RT sperm (P < 0.01)

Effect of egg weight on ostrich (Struthio camelus) chick weight and growth

The aim of this paper is to evaluate the effects of the age of ostriches and month of laying on egg production and chickgrowth. On a small ostrich farm egg production, egg incubation and chick growth from hatching to 56 days of age wererecorded from 2000, when the breeders were 5 years old, until 2002. Ostriches were kept in groups and fed commercialfeed. In all, 568 eggs were laid and weighed at laying and during incubation (at 15th and 30th day of incubation), while353 chicks were weighed at hatching, 7, 14, 28 and 56 days of age.The female’s productivity was calculated assuming a laying of 3.5 eggs per week and ranged between 45% and 48%.The fertility was around 70% with a peak of 74% recorded in 2001. The hatchability of all eggs was higher than 62%with a peak of 72% in 2001, while the hatchability of fertile eggs was higher than 90%. In each year the number of eggslaid increased from March to July, productivity showed a positive trend from May to June, while the fertility and hatchabilityof all eggs, as well as fertile eggs, was unaffected by year and month. As the hens aged, the egg mass grew constantlywith an increase of about 8%. During the first 30 days of incubation the egg weight decreased with the percentagesof weight loss around 10.0%. At hatching, the weight of chick ranged between 765 g and 847 g, respectively, in2000 and 2002. Egg weight influenced the hatching weight showing a linear relationship (R2=0.84). The effect of eggweight on the chick weight decreased as the chick grew. At 56 days of age, only the effect of year is significant. Themonth of laying did not demonstrate any effect on chicken weight

Morphometric characteristics of "Tinca Gobba Dorata del Pianalto"

Forty six T3 tench from 55 to 100 g, were examined in order to set up a first database on morphological traits. Linear (total, fork, head, trunk, caudal peduncle, muscular body and tail length, height, thickness and circumference) and ponderal (total body, viscera, liver and gonad weight) parameters have been measured. Several morphometric indexes were calculated for each sex. The results showed there was no significant difference for K value between sexes. The relationship between C and M can be described with a quadratic regression (R2=0.81)