Effect of temperature, anaerobiosis, stirring and salt addition on natural fermentation silage of sardine and sardine wastes in sugarcane molasses.

Conditions for a natural fermentation during ensilage of sardines or their waste in sugarcane molasses (60:40 w/w) were evaluated regarding the effect of temperature (15, 25 and 35 degrees C), anaerobiosis (closed vs. open jars), daily stirring of the mixture, and salt addition to the initial mix at 5% (w/w) level. Successful natural fermentation took place in sardine silages incubated at 25 or 35 degrees C in open jars to reach a pH of 4.4 in about 2 and 1 weeks, respectively. For samples kept at 15 degrees C, the pH decline was very slow and pH did not decrease below 5.5 after one month of incubation. At 25 degrees C, the most favorable conditions for silage of sardine waste in cane molasses, as evidenced by the fastest decline in pH to a stable value of about 4.4, were achieved in closed jars and with daily stirring of the mix. The pH 4.4 was reached in one week with an advance of at least 3 days compared to the other conditions (open jars and closed jars without daily stirring). Addition of salt at 5% (w/w) in the mix before incubation inhibited the fermentation process.

Effect of dietary crude proteins on the reproductive function in the postpartum dairy cow.

The study was conducted on 216 dairy cows. Samples of feeds distributed to cows were collected monthly for the purpose of determining their content in dry matter, energy, crude proteins and mineral matter. Milk samples were collected weekly for every cow from newly calved cows until confirmation of pregnancy by rectal palpation at least 2 months after artificial insemination. These samples were used for progesterone assays in skimmed milk, in order to assess the interval between calving and return to ovarian activity [C-ROA], calving and first insemination [C-I1], calving and conception [C-C] and number of inseminations per conception (nI/C). Results have shown a significant negative correlation between the duration of [C-ROA] and [C-C] intervals and the dietary content in crude proteins (r = -0.720, p < 0.05 and r = -0.914, p < 0.01 respectively).