Enzymological, Histological and Serum Biomarkers Responses of Snubnose Pompano on Complete Replacement of Fishmeal Using Cottonseed Meal Supplemented With Lysine and Methionine in the Diet

In a feeding experiment, cottonseed meal (CSM) was used to replace fishmeal (FM) in the diet of snubnose pompano supplemented with lysine and methionine to assess the growth, nutritive profile, hematological, histological and stress biomarkers response. Experimental fishes were randomly stocked in five treatments each with triplicates. Five isonitrogenous and isolipidic diets with graded level of CSM (0, 8.7, 17.4, 26.0 and 34.7%) as replacement for FM protein (0, 25, 50, 75, and 100%) were formulated and fed to respective treatments. Comparison between various parameters among the treatments was made using orthogonal polynomial contrasts to indicate the statistical significance. Higher alkaline phosphatase, acid phosphatase, lactate dehydrogenase, malate dehydrogenase, aspartate and alanine aminotransferase activities were observed in 0CSM group and followed by 100CSM group as higher inclusion level of CSM with higher free gossypol content did not affect the metabolic enzyme activities. The maximum muscular free gossypol accretion of 1.28 mg kg-1 (on wet basis) was recorded in 100CSM group which was very well below the critical limit set by FDA. As a conclusion, fishmeal can be completely replaced using cottonseed meal in the diet of pompano without adverse effect on growth, metabolism and general health.

Effectiveness of the toxin-degrading strain screening strategy: Deficiency and improvement in screening the gossypol-degrading microorganism Aspergillus niger

The effectiveness of the classic screening strategy was verified, by duplicating and verifying the degradation of gossypol by the Aspergillus niger. It can reduce the free gossypol content through biosorption but has no effect on the total gossypol content and cannot effectively degrade gossypol. And the most interesting thing we found the strain can secrete agarase, utilise agar as carbon source. In this case, that will mislead researchers and lead them to make wrong judgments. That turns out the usual methods of previous screening strategies are not rigorous enough, the classic screening method has defect in screening toxin-degrading strain, so agar control group should be added. In this study, some suggestions are put forward to optimise the same type of experiments and broaden the idea of detoxification by microorganisms and provide reference for screening effective toxin-degrading microorganisms.

Meat characteristics of cattle fed diets containing whole cottonseed

ABSTRACT Sensory and instrumental analyses evaluated the meat and fat characteristics of feedlot-finished steers fed a diet containing cottonseed. Global impression, texture, meat color, and fat color were assessed. Thirty Nellore bulls with an average age of 30 ± 6 months and initial body weight of 382.7 ± 28.4kg were kept in feedlot stalls and fed the following cottonseed levels: 0; 2.22 %; 4.44 %; 6.66 %; 8.88 %; 11.11 % of the dietary dry matter. The cottonseed used in this experiment had an average free gossypol content of 4.5g/kg of cottonseed. The overall impression of the samples, assessed by the triangle test for difference, did not differ for more than 62 % of the panelists (P>0.01). The shear strength of roasted meat varied from 6.00 to 6.54kg. According to texture profile analysis (TPA), the hardness, springiness, and chewiness of roast meat ranged from 24.15 to 28.01 N, 0.52 to 0.56, 8.42 to 11.01 N, respectively; of raw meat, 9.51 to 13.86 N, 0.26 to 0.29, and 1.38 to 1.81 N, respectively. The different treatments did not affect meat texture, meat color, or fat color (P>0.05). Meat color, luminosity, and red intensity ranged from 37.71 to 42.85, 20.68 to 25.25, and 6.74 to 8.61, respectively; fat color, luminosity, and yellow intensity ranged from 62.26 to 63.78, 11.13 to 11.62, and 10.53 to 10.86, respectively. Cottonseed intake of up to 1.13kg/animal/day, equivalent to a free gossypol intake of 5.05g/animal/day, in place of soybean meal and ground corn, did not significantly change the global sensory impression, texture, and color of the meat and fat.

Gossypol content of cotton free commercial feed for dairy cows

Gossypol is a yellow pigment occurring in all parts of cotton plants, with the highest levels found in seeds, and it exhibits a variety of toxic effects. Few data are available on the content of gossypol in the commercial complementary feed and in feed raw materials. The present study was focused on the investigation of the presence of free gossypol in commercial complementary feed not containing cotton. A total of 50 samples of commercial complementary feed for dairy cows were performed in 29 feed mills both using and not using cotton as feed material. The free gossypol contamination resulted under the detection limit of the technique (4 mg/kg) in 12 out of 50 samples analysed and ranged from 4 to 20 mg/kg in 28 samples. In 10 samples the level of free gossypol ranged from 20 to 29.5 mg/kg. Average contamination of samples was 12.2±9.2 SD mg/kg. No significant difference (P=0.571) was shown in free gossypol concentration between feed produced in <em>cotton free</em> plants and in plants where cotton is used as feed material. Free gossypol content detected in the present study allows considering complementary feed for dairy cows not at risk. On the other hand, the detection of free gossypol in cotton free complementary feed, probably attributable to cross contamination of feed materials upstream of the feed mill, should be further investigated.