Digestive enzyme activity in juvenile Nile tilapia (Oreochromis niloticus, L) submitted to different dietary levels of shrimp protein hydrolysate

The effect of different dietary concentrations of shrimp protein hydrolysate (SPH) on digestive enzyme activity of Nile tilapia juveniles was evaluated. SPH concentrations in diets were 0, 15, 30 and 60 g kg^?1 (treatments SPH0, SPH15, SPH30 and SPH60, respectively). Hemoglobin, azocasein, BApNA (Nα-benzoyl-dl-arginine-p-nitroanilide), SApNA (Suc-Ala-Ala-Pro-Phe p-nitroanilide), aminoacyl of β-naphthylamide and starch were used as substrates for enzyme activity determinations. The activity of total alkaline protease was significantly higher (P < 0.05) in fish under SPH15 and SPH60 treatments than in the control (SPH0). However, the effect was not dose-dependent. Substrate-SDS-PAGE was also performed to evaluate changes in the profile of Nile tilapia digestive proteases caused by SPH. Substrate-SDS-PAGE revealed 12 active proteolytic bands, eight of which responded to SPH dietary incorporation. Inhibition substrate-SDS-PAGE indicated a decrease in the activity of three enzymes, with trypsin activity decreasing with the increase of SPH concentration, whereas the opposite occurred for two aminopeptidases. Distinct protease profiles were also found for each treatment, suggesting adaptability of digestive proteases from Nile tilapia to the different diets.     

Intake and ingestive behavior of lambs fed diets containing ammoniated buffel grass hay

This study aimed to evaluate the effect of diets with ammoniated buffel grass hay on the ingestive behavior of feedlot lambs. Thirty-two sheep of no defined breed with an average body weight of 17.7?±?1.8 kg were used. A completely randomized design with four treatments (0, 18, 36, and 54 g/kg dry matter (DM) basis) and eight repetitions was used. Ingestive behavior, rumination, and idle time were similar (P?>?0.05) among the diets containing ammoniated buffel grass hay, with mean values of 294.5, 554.44, and 594.25 min per day, respectively. Regarding the chews, all of the variables resulted in similar behavior (P?>?0.05). The quadratic effect (P?<?0.05) observed for daily intake can be explained based on the amount of DM and neutral detergent fiber (NDF) per meal per rumination. There was no effect of urea levels from the ammoniation (P?>?0.05) on the efficiency of DM and NDF consumption. However, the rumination efficiency of DM and NDF showed a quadratic effect (P?<?0.05). Thus, the use of ammoniated buffel grass hay with urea in lamb diet affects the ingestive behavior by increasing the rumination efficiency, increased intake, and feed utilization.     

Seroprevalence and risk factors for leptospirosis in cattle,sheep, and goats at consorted rearing from the State of Piauí, northeastern Brazil

Leptospirosis is an endemic disease in Latin America, caused by pathogenic bacteria of the genus Leptospira. It is considered one of the main causes responsible for the negative economic impact on global livestock by causing reproductive problems. The research aimed to determine the prevalence of leptospirosis in cattle, sheep, and goats at consorted rearing in the micro-region of Teresina, Piauí state, northeastern Brazil, as well as to identify prevalent serovars and risk factors associated with seroprevalence. Serum samples were analyzed in 336 sheep, 292 goats, and 253 cattle using microscopic agglutination test (MAT). Overall, 378 samples were positive to MAT, with seroprevalence of 42.9%. The prevalences in cattle, sheep, and goats were 50.5, 40.5, and 34.6%, respectively. All herds presented at least one seropositive animal; the Hardjo/Wolffi serovar association was the most common in cattle and Icterohaemorrhagiae in goats and sheep. Beef production (OR?=?4.9), cattle herd over 35 animals (OR?=?4.0), feeding on pasture (OR?=?6.4), weir and/or stream as water source (OR?=?2.1), and no veterinary services (OR?=?2.9) were risk factors for cattle infection. For sheep, intensive management system (OR?=?5.3), suspended slatted facilities (OR?=?2.2), more than 20 sheep in reproductive age (OR?=?1.9), and absence of deworming (OR?=?3.5) were the risk factors, while for goats, the identified risk factors were sheep herd over 52 animals (OR?=?1.9) and no veterinary services (OR?=?1.8). We conclude that the infection was spreading in consorted herds in this region. Thus, it would be interesting and important to conduct educative activities to farmers on the economic impacts of this disease and the need of preventive and control strategies mainly focused on sanitary measures and animal handling.     

Detection of the first lectin with antimicrobial activity present in serum of the Amazonian fish tambaqui Colossoma macropomum

Tambaqui Colossoma macropomum is the most important Amazonian native species in South American aquaculture. Innate immunity at least partially depends on the recognition of pathogen-associated molecular patterns by receptor-recognizing pathogens (PRRs). Some PRRs have been characterized in fishes, and several studies have focused on the role of lectins in the immune system of various fishes. Lectins are proteins that specifically recognize carbohydrates and which have important biological functions. Tambaqui serum lectin (ComaSeL), which was identified on the basis of its hemagglutinating activity, was pre-purified, biochemically characterized, and used in assays of antibacterial activity against pathogenic bacteria in freshwater fishes. A study of the seasonality of this lectin was performed. Comasel activity was stable at a pH between 4.0 and 9.0 and lost 100?% of its activity at 70?°C. It recognized the carbohydrates d-galactose, 1-O-methyl-d-galactopyranoside, and d-fucose, showing antibacterial activity for Gram-negative bacteria. Its activity showed significant differences between the summer and winter (p?<?0.05, Tukey test), thereby corroborating observations that tambaqui becomes more susceptible to mortality from diseases caused by bacteria and fungi during the winter. With this information, new tools may be developed for gaining a better understanding of the role of these proteins in the immune system of the tambaqui, ultimately resulting in the improved management of this fish by pisciculturists.     

Reproductive Development of Santa Inês Rams During the First Year of Life: Body and Testis Growth,Testosterone Concentrations,Sperm Parameters,Age at Puberty and Seminal Plasma Proteins

We have investigated the reproductive development of the tropically adapted Santa Inês ram, the most common hair sheep in Brazil. From 8 to 48 weeks of age, 16 animals were evaluated for body and testis growth, semen parameters, testosterone concentrations and seminal plasma proteins, using two‐dimensional SDS‐PAGE. Animals were weaned at 30 days and kept in feedlots thereafter, receiving hay, concentrate (18% of crude protein) and mineral supplement. Body weight increased from 12.3 ± 0.7 to 54.3 ± 1.6 kg between 8 and 48 weeks (p < 0.05), but changes in thoracic perimeter and scrotal circumference were non‐significant after 36 weeks (p > 0.05). The percentage of motile sperm increased slowly until 23 weeks and more rapidly after that age, but significant changes in progressive motility occurred after 25 weeks. Presence of abnormal sperm related inversely to age. Most significant changes in sperm concentration occurred between 38 and 44 weeks (0.38 ± 0.05 to 1.14 ± 0.24 × 10⁹ cells/ml, p < 0.05) and testosterone reached its highest concentrations at 42 weeks, decreasing afterwards. Rams reached puberty at 28.2 ± 0.8 weeks. The number of protein spots on seminal plasma gels was similar from 15 to 18 weeks (45 and 47 spots; p > 0.05), increased until 24 weeks (141 spots) and 28 weeks (170 spots; p < 0.05) and remained without significant (p > 0.05) changes from 28 to 48 weeks (186 ± 10 spots). Furthermore, the intensity of selected spots on 2D maps increased (p < 0.05) between 15 and 28 weeks, which preceded or coincided with the main developmental changes in sperm motility and percentage of defective sperm in the ejaculates. These results will support future studies designed to characterize specific seminal plasma proteins whose expression relate to the development of testis, epididymis and accessory sex glands.     

Analysis of multicriteria in the practice of environmental services in areas of watersheds

ABSTRACT

Watersheds have become strategically important for the survival of cities due to the accelerated increase in both the demand and the rapid deterioration of the water intended to supply the urban populations. The present article aims to present the applicability of the “multicriteria method” to help the Government of the State of Sao Paulo, Brazil organize payment for environmental services for watershed protection using the “Delphi method” as the principal methodology. This article consists of a review of the literature and a case study of the Mina d’Água program from the State Secretary of the Environment (within the Government of São Paulo) in partnership with other municipalities (city by river basin). The article also covers the advent of pertinent climate change laws. The positive results in the use of the Delphi method represent a fruitful tool to facilitate communication between groups of experts and the public, encouraging better judgment and a more consistent decision-making process.     

Food safety in raw milk production: risk factors associated to bacterial DNA contamination

While human illness from milkborne pathogens may be linked to contamination of the product after pasteurization or improper pasteurization, such diseases are usually associated with consumption of raw milk or its by-products. Molecular biology tools were applied to investigate contamination by Listeria monocytogenes, Salmonella spp., some pathogenic strains of Escherichia coli, and Campylobacter jejuni in 548 raw milk samples from 125 dairy farms established in two regions from southern Brazil. Moreover, 15 variables were evaluated for their association with raw milk contamination levels, and the risk factors were determined by multiple regression analysis. Salmonella spp. were more frequently detected, followed by pathogenic E. coli. There was difference in contamination index between the regions, in which risk factors such as temporary cattle confinement, low milk production, low milking machine cleaning frequency, and milk storage area without tile walls were identified. The risk factors were specific to each region studied. Nevertheless, the data can be used to improve milk quality of dairy farms/herds with similar management practices.     

Assessment of the metabolic,protein, energy,and liver profiles of lambs finished in a feedlot and receiving diets containing groundnut cake

Forty-five crossbred Dorper × Santa Inês lambs were selected to assess the effect of replacing soybean meal by groundnut cake metabolic profile and histopathological evaluation of the kidney and liver tissues. The animals were 5 months old on average with a 24.5?±?5.3 kg initial body weight which were maintained fed in feedlot with groundnut cake (0, 25, 50, 75, and 100 %) as the replacement for soybean meal. Confinement lasted 84 days, and on the last day, the animals were fasted and slaughtered. A completely randomized design with five treatments and nine repetitions was used. Blood samples were collected from the jugular vein of each animal to evaluate the metabolic, protein, energy, and liver profiles of lambs. No effect was observed on protein, energy, or enzymatic profiles, which remained within the normal range for sheep. A histopathological examination was performed, and no deleterious effects from groundnut cake were observed in the liver or kidney tissues. Groundnut cake as a replacement for soybean meal can be used as an alternative protein source up to 100 % because it does not affect the metabolic, protein, and energy profiles or the liver and kidney functions of the growing sheep for slaughter.     

Cooled Storage of Canine Semen: in vitro Effects of Different Concentrations of an Antibiotic Combination on Growth of Mollicutes

The aim of this study was to examine effects of an antibiotic combination at different concentrations on growth of mycoplasma and ureaplasma during cooled storage of canine semen (n = 20). Semen aliquots were diluted with Tris–citric acid–fructose–egg yolk extender containing either 1.0 g/l streptomycin and 0.6 g/l benzylpenicillin (control) or a combination of gentamycin, tylosin, lincomycin and spectinomycin (GTLS‐1: 0.25, 0.05, 0.15 and 0.3; GTLS‐2: 0.5, 0.1, 0.3 and 0.6; GTLS‐3: 1.0, 0.2, 0.6 and 1.2 g/l). Samples were assessed for motility and membrane integrity by computer‐assisted sperm analysis immediately after dilution and at 24, 48 and 72 h of cooled storage. Morphologically, normal spermatozoa were determined, and bacterial culture was performed at 24 and 72 h. Mycoplasma spp. were detected in 14 of 20 ejaculates (70%) with severe growth in 12 samples. A reduction but not total elimination of mycoplasma growth occurred in all GTLS extenders with the most pronounced reduction in group GTLS‐3 (control vs GTLS‐1 and GTLS‐2 p < 0.05, control vs GTLS‐3 p < 0.001). Ureaplasmas were detected in four ejaculates, and growth was reduced to the same extent in GTLS and control extender. Progressive motility in all groups, total motility in groups GTLS 1–3 and percentage of membrane‐intact spermatozoa in groups GTLS 2 and 3 decreased slightly (p < 0.05) over time. In conclusion, dilution of canine semen with GTLS extender has no major detrimental effects on spermatozoa during cooled storage. It reduced the growth but did not totally eliminate mycoplasmas and ureaplasmas from cooled‐stored dog semen.