Changes of Circulating Total and Free Iodothyronine in Horses After Competitive Show Jumping With Different Fence Height

The effect of exercise on circulating T₃, T_4, free (f) T₃, and fT₄ concentrations were studied before and after competitive show jumping in 24 trained jumper horses with an age range of 11–13 years and having the same level of show experience. All horses, randomly divided into three groups paired by gender, participated in three competition levels with the same circuit design over 10 fences, with five upright and five cross-pole fences .The three fence height groups were group I (n = 8), 1.10 m; group II (n = 8), 1.20 m; and group III (n = 8), 1.30 m. Repeated measures analysis of variance showed a statistically significant effect of competitive exercise on fT₃ changes in all groups, whereas the effect of competitive exercise on T₃ changes was exclusively seen in group III. Two-way repeated measures analysis of variance showed that the effect of fence height (P = .0002) and performance results were significant (P = .0486) only for T₃ changes. Performance also affected fT₃ changes (P = .0152). No significant correlation was found between total and free iodothyronines. These results suggest a dependence of T₃ and fT₃ changes on exercise-related variables and performance results and that the thyroid response is different with respect to the different exercise-related variables, such as the varying level of difficulty and performance results.     

Effect of dietary carbohydrate to lipid ratios on growth,digestive enzyme and blood metabolites of juvenile Brazilian sardines,Sardinella brasiliensis (Steindachner, 1879)

The limited availability of live bait for capturing skipjack tuna, Katsuwonus pelamis, is a bottleneck to increasing tuna production in many parts of the world. Therefore, a nutrition trial was performed to contribute to the production of the Brazilian sardine, Sardinella brasiliensis, for use as live bait. This study determined the best dietary carbohydrate to lipid ratio (CHO:L) for juvenile Brazilian sardines based on growth performance, feed utilisation, body composition, blood metabolites and digestive enzyme activity. Six isoenergetic and isonitrogenous diets were formulated with increased CHO:L ratios (2.05, 3.41, 4.15, 5.11, 5.80 and 6.72). Each diet was randomly assigned to triplicate groups of 100 fish with mean initial body weight of 2.97 ± 0.51 g, which were fed four times a day to apparent satiation. Survival was not affected by differences in diet, however, a low CHO:L ratio stimulated growth. Juveniles fed with a rich‐carbohydrate diet inhibit feed intake and protein intake. Body lipid increased as dietary lipid increased and was inversely correlated to body moisture. The diets did not affect the juvenile's blood metabolites. Alkaline and acid protease activities were not significantly different, but lipase and amylase responded positively to the dietary lipids and carbohydrates. Using segmented regression, the optimum CHO:L ratio for maximum weight gain of juvenile Brazilian sardines was estimated to be 3.41, which contain approximately 300 g kg^?1 carbohydrate and 88 g kg^?1 lipid.     

Re-ensiling effects on inoculated sorghum: Intake,apparent digestibility,nitrogen balance,and animal feeding behaviour

This study aimed to determine whether using inoculants and re-ensiling in sorghum silages affect the intake and feeding behaviour, apparent digestibility, digestible energy, and nitrogen balance of sheep in maintenance. Half the sorghum was inoculated on the day of harvest, and the other half received the same inoculation volume but with water. Sorghum was ensiled in 100 experimental metal drum silos of 200 L covered with plastic: 50 silos with inoculants and 50 without them. After 56 days, 25 drums with inoculants and 25 without were exposed to air for 48 h. The other silos remained closed. The treatments were arranged in a 2 × 2 factorial scheme with inoculation and re-ensiling. The sheep received the silages after 211 days of ensiling and 155 days of re-ensiling to determine the intake, apparent digestibility, and feeding behaviour of animals. The experimental design was a simultaneous double 4 × 4 Latin square. The re-ensiling process increased silage pH, N-NH₃.TN⁻¹, butyric acid, and propionic acid. The inoculant increased propionic acid in ensiled and re-ensiled silages. Lactic acid concentration presented a statistical interaction with the inoculated and ensiled silage, 58% higher than the other treatment averages. The ADFap digestibility showed a complex interaction, in which the control ensiled and the inoculated and re-ensiled silages were about 35% lower than the inoculated ensiled silage. The Nbal:Nint ratio (g.g⁻¹) in the inoculated and re-ensiled silage had lower nitrogen retention than intake compared with the other treatments. These results indicate that exposing inoculated silages to air does not compromise their use in sheep feeding.     

In Vivo Nutritional Assessment of the Microalga Nannochloropsis gaditana and Evaluation of the Antioxidant and Antiproliferative Capacity of Its Functional Extracts

Nannochloropsis gaditana is a microalga with interesting nutritional and functional value due to its high content of protein, polyunsaturated fatty acids, and bioactive compounds. However, the hardness of its cell wall prevents accessibility to these components. This work aimed to study the effect of a treatment to increase the fragility of the cell wall on the bioavailability of its nutrients and functional compounds. The antioxidant and antiproliferative capacity of functional extracts from treated and untreated N. gaditana was assessed, and the profile of bioactive compounds was characterized. Furthermore, to study the effect of treatment on its nutrient availability and functional capacity, an in vivo experiment was carried out using a rat experimental model and a 20% dietary inclusion level of microalgae. Functional extracts from treated N. gaditana exhibited higher antioxidant activity than the untreated control. Furthermore, the treated microalga induced hypoglycemic action, higher nitrogen digestibility, and increased hepatic antioxidant activity. In conclusion, N. gaditana has interesting hepatoprotective, antioxidant, and anti-inflammatory potential, thus proving itself an ideal functional food candidate, especially if the microalga is treated to increase the fragility of its cell wall before consumption.     

Surface physicochemical properties of globulin-P amaranth protein

Globulin-P, the polymerized 11S amaranth globulin, is composed of 280 kDa unitary molecules (UM, 23%) and aggregates larger than 500 kDa (A, 70%). Antibodies against these proteins were prepared to study their surface characteristics and to assess their homology with other storage proteins. Results showed that globulin-P unitary molecules and aggregates had similar reactive surfaces. A polypeptide of 56 kDa was found to be the most reactive to the antibodies assayed, followed by the acidic polypeptides. Such results support previous information, according to which these polypeptides appeared to be the most exposed on the molecule surface. Globulin-P fraction presented cross-reactivity with the remaining amaranth protein fractions: 11S-globulin, glutelins, and albumins. Globulin-P and 11S-globulin showed similar reactive surfaces whereas glutelin and albumins presented a lower cross-reactivity. The reactivity of the glutelin fraction depended on its sequence. Globulin-P fraction presented cross-reactivity with quinoa globulins, and to a lesser extent with globulins of sunflower and rice. Moreover, the anti-Gp serum was unable to detect either conformational or sequence epitopes in globulins of soybean, wheat, buckwheat, rice, and rye.     

Pesticide Use and Mycotoxin Production in Fusarium and Aspergillus Phytopathogens

The major mycotoxigenic species of Fusarium and Aspergillus phytopathogens have been identified in this review. Since fungicides are widely used to control crop diseases caused by these fungi, it is pertinent to assess efficacy with respect to mycotoxin production. In both laboratory studies with pure cultures of phytopathogens and field trials with crop plants, the overall evidence concerning the effectiveness of fungicides is contradictory and in certain cases somewhat unexpected. In particular, at sub-lethal doses of a number of fungicides including carbendazim, tridemorph, difenoconazole and tebuconazole with triadimenol, mycotoxin production from Fusarium phytopathogens may increase. Furthermore, the efficacy of propiconazole and thiabendazole in the control of deoxynivalenol production from F. graminearum is not consistent. Evidence has been presented to suggest, for the first time, that fungicide-resistance in F. culmorum may be accompanied by a more persistent pattern of mycotoxin production. The limited evidence on the effects of fungicides on mycotoxin production in Aspergillus species is also conflicting. Under laboratory conditions, miconazole and fenpropimorph have been shown to increase aflatoxin production from A. parasiticus. Moreover, fenpropimorph increased production of the more toxic aflatoxin B1. Since fungal infection of plant products is often preceded by insect damage, there is interest in the effectiveness of insecticides to reduce infestation, infection and mycotoxin contamination. Additionally, insecticides may be effective in their own right, causing a direct effect on mycotoxin synthesis. The bulk of the evidence relates to effects on aflatoxin (AF) components B1, B2, G1 and G2. Under laboratory conditions, AFB1 production was most resistant to inhibition by insecticides, followed by AFG1, AFG2 and AFB2. This pattern of inhibition was particularly consistent for the organophosphorus insecticides. In one field study, Bux and carbaryl were considerably more effective than naled in reducing AFB1 contamination of maize kernels. It is concluded that if pesticide control is to be more effective in the future, additional criteria may be required in developing evaluation protocols for candidate compounds. In particular, the issue of fungicide-resistance in relation to mycotoxin production needs to be addressed in a concerted programme of research. Additionally, the potential of breeding and selecting cultivars resistant to disease caused by toxigenic fungi needs to be exploited in a parallel search for an environmentally acceptable solution to the question of mycotoxin contamination of plant products.     

Environmental and genetic variation of the effective radiative properties of the coat of Holstein cows under tropical conditions

Morphological characteristics, coat effective radiative properties, and the percentage of white colour were measured in the coats of 973 Holstein cows, and estimates of the genetic parameters were obtained for these traits, except morphological characteristics. The results showed that white coats are more dense with long, thin hairs, while the black coats are less dense with short, thick hairs. Effective transmissivity is greater in the less-dense coats with short, thin hairs, independently of coat colour. Effective reflectivity depends more on the variation in the radiative properties of the coat and skin surface rather than on the morphological characteristics of the coat. Effective absorptivity is greater in black and dense coats with long, thick hairs, than in the white and less-dense coat with short, thin hairs. All heritability estimates were of low magnitude, except for the percentage of white coat colour.     

Antimicrobial resistance and molecular epidemiology of streptococci from bovine mastitis

Streptococcus agalactiae (Group B Streptococcus, GBS), Streptococcus dysgalactiae subsp. dysgalactiae (Group C Streptococcus, GCS) and Streptococcus uberis are relevant mastitis pathogens, a highly prevalent and costly disease in dairy industry due to antibiotherapy and loss in milk production. The aims of this study were the evaluation of antimicrobial drug resistance patterns, particularly important for streptococcal mastitis control and the identification of strain molecular features. Antimicrobial resistance was assessed by disk diffusion against amoxicillin–clavulanic acid, cefazolin, cefoperazone, pirlimycin-PRL, rifaximin, streptomycin, chloramphenicol, erythromycin-ERY, gentamicin, tetracycline-TET and vancomycin. Genotypic relationships were identified using pulsed-field gel electrophoresis (PFGE), macrolide and/or tetracycline resistance gene profiling, GBS capsular typing, GBS virulence gene profiling and GBS and S. uberis multi locus sequence typing (MLST).The majority of the isolates were susceptible to all drugs except to aminoglycoside, macrolide, lincosamide and tetracycline. Close to half of the TET resistant isolates have tetO and tetK and almost all ERY–PRL resistant isolates have ermB. A high degree of intra-species polymorphism was found for GCS. The GBS belonged to ST-2, -554, -61, -23 lineages and five new molecular serotypes and human GBS insertion sequences in the cpsE gene were found. Also, GBS of serotype V with scpB and lmb seem to be related with GBS isolates of human origin (same ST-2 and similar PFGE). Overall our results suggested that different therapeutic programs may have been implemented in the different farms and that in most cases clones were herd-specific.     

Growth hormones therapy in immune response against Trypanosoma cruzi

Growth hormone (GH) is an important hypophyseal hormone that is primarily involved in body growth and metabolism. In mammals, control of Trypanosoma cruzi parasitism during the acute phase of infection is considered to be critically dependent on direct macrophage activation by cytokines. To explore the possibility that GH might be effective in the treatment of Chagas’ disease, we investigated its effects on the course of T. cruzi infection in rats, focusing our analyses on its influences on parasitemia, NO, TNF-α and IFN-γ concentration and on histopathological alterations and parasite burden in heart tissue. T. cruzi-infected male Wistar rats were intraperitoneally treated with 5 ng/10 g body weight/day of GH. Animals treated with GH showed a significant reduction in the number of blood trypomastigotes during the acute phase of infection compared with untreated animals (P < 0.05). For all experimental days (7, 14 and 21 post infection) of the acute phase, infected and GH treated animals reached higher concentrations of TNF-α, IFN-γ and nitric oxide as compared to untreated and infected counterparts (P < 0.05) Histopathological observations of heart tissue revealed that GH administration also resulted in fewer and smaller amastigote burdens, and less inflammatory infiltrate and tissue disorganization, indicating a reduced parasitism of this tissue. These results show that GH can be considered as an immunomodulator substance for controlling parasite replication and combined with the current drug used may represent in the future a new therapeutic tool to reduce the harmful effects of Chagas’ disease.