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991.
Substituting goats' milk for cows' milk could improve the quality of dairy products, because it adds new sensorial characteristics. The aim of this study was to develop a type of yoghurt using goats' milk (25, 50, 75 and 100%) in place of cows' milk and to compare their characteristics. Physicochemical, microbiological and sensory characteristics were evaluated using a nine‐point hedonic scale and purchase intention test. The data obtained in the physicochemical analysis were submitted to regression analysis and the sensory results were evaluated through analysis of variance. Among the physicochemical characteristics of the yoghurts, variation (P < 0.05) of ash, acidity and lactose was observed. Tasters in the sensory analysis indicated that yoghurts up to 50% of goats' milk received favorable averages; with lower scores for higher goats' milk concentrations (75% and 100%). No difference was reported in acidity. Replacing cows' milk with goats' milk in yoghurt preparation promotes variations in the physicochemical characteristics for ash, acidity and lactose. However, it does not cause alterations in the sensory attributes (50% goat milk) and therefore could be considered as an alternative for the production of dairy products. © 2016 Japanese Society of Animal Science  相似文献   
992.
A genome-wide association study for morphometric traits was conducted in 184 Quarter Horses, 120 from a racing population, and 64 from a cutting population, which were genotyped using the Illumina EquineSNP50 chip. Association analysis was performed with 42,058 single-nucleotide polymorphisms (SNPs) (after quality control) using Qxpak5 software. The following traits were measured: weight (W), rump length (RL), and body length (BL). These morphometric traits are important for the best performance in race and cutting events. For weight, three SNPs associated (P < .0001) were found on chromosomes (Equus caballus autosomes [ECA]) 2 and 3. For rump length, eight SNPs associated (P < .0001) were found on ECA 2, 3, 6, 7, 9, 21, and 26. On ECA 3 and ECA 8, two SNPs were associated (P < .0001) with body length. So, a total of 13 important chromosomal regions were identified with Q values of 0.53 (SNPs for W), 0.40 (SNPs for RL), and 0.99 (SNPs for BL). Positional and functional candidate genes emerging from this study were WWOX and AAVPR1A. Further studies are required to confirm these associations in other populations.  相似文献   
993.
Leptospirosis is a bacterial zoonotic disease that causes severe reproductive problems in livestock and generates economic losses for farmers. This study aimed to determine the seroprevalence of anti-Leptospira antibodies in small mammals, both wild and domestic, in two distinct areas of the semi-arid region of northeastern Brazil: the National Park of Serra das Confusões (NPSC), state of Piauí, a preserved area; and rural areas in the municipalities of Petrolina and Lagoa Grande, state of Pernambuco, non-preserved areas. Serum samples were evaluated using the microscopic agglutination test (MAT). Approximately 4% (6/152) of the wild animals were positive, all of them in the non-preserved area. Overall, the seroprevalence rates among goats and sheep were 13.4 (77/576) and 4.6% (24/518), respectively, confirmed in both areas. The seroprevalence rates in dogs and cats were 5.6 (10/180) and 4.7% (2/43) and were determined only in the non-preserved area. The risk factors associated with Leptospira spp. infection were as follows: ages of 1–3 and > 3 years for goats and sheep, region (preserved area) for goats, intensive management system for sheep, and region (non-preserved area) for dogs and wildlife. The present study confirmed the presence of circulation of Leptospira spp. in both of these areas of the Caatinga biome, as well as a variety of serotypes in these areas.  相似文献   
994.
Our aim with this study was to evaluate the consumption, performance, quantitative characteristics of carcasses, biochemical profile, plasma levels of ghrelin and leptin, expression of the receptor for ghrelin (GHS-R1a) in the hypothalamus and duodenum, and the number of goblet cells in the duodenum of calves subjected to milk volume restriction and supplemented with 2-hydroxy-4-(methylthio)butanoic acid (HMTBa). We used 21 Holstein mixed-breed calves, aged between 3 and 15 d with an average weight of 36.8 kg, and housed in pens with troughs for hay, concentrate, and water. The study included two consecutive experimental periods (first period [P1] and second period [P2]) of 21 d each, with 7 d of adaptation to the diet and facilities. The calves were distributed in a completely randomized design in three treatments with seven repetitions. 1) Control: 6 liters of milk/d during P1 and 6 liters of milk/day during P2; 2) RES (milk restriction): 3 liters of milk/day during P1 and 6 liters of milk/day during P2; and 3) RES + HMTBa: 3 liters of milk/day during P1 and 6 liters of milk/day during P2 + 3.3 g of HMTBa/day in both periods. HMTBa was supplied in milk, and the amount of concentrated ration and hay provided and leftovers were recorded daily to estimate dry matter (DM) and crude protein consumption. Mean daily weight gain (DWG), final weight (FW), and feed conversion (FC) were obtained at the beginning and at the end of each 21-d period. Plasma concentrations of ghrelin and leptin, triglycerides, total protein, urea, lactate, creatinine, alkaline phosphatase, and cholesterol were measured for P1 and P2 at the end of each 21-d period. At the end of P2, animals were slaughtered; sections of the duodenum were collected to evaluate the expression of GHS-R1a and quantity of goblet cells; hypothalamus was used to evaluate the expression of GHS-R1a; rumen was used to evaluate the thickness of epithelium and keratin and the density, height, and width of ruminal papillae. In P1, total DM consumption, FW, DWG, glucose, and triglycerides were lower in the RES and RES + HMTBa groups (P < 0.001). In P2, there was an improvement in the FC of the RES + HMTBa group (compared with Control and RES groups) and a lower urea concentration in the RES group (compared with Control and RES + HMTBa groups) (P < 0.001). No differences were observed among groups regarding hormonal concentrations, histological parameters, and GHS-R1a expression in the duodenum and hypothalamus. Therefore, milk restriction combined with HMTBa supplementation promoted greater compensatory gain by a mechanism independent of changes in GHS-R1a expression and hormone levels of ghrelin and leptin.  相似文献   
995.
This study was carried out aiming to evaluate the effects of yeast or monensin supplementation on dry matter intake, nutrients digestibility, ruminal volatile fatty acids profile, ruminal pH and ammonia concentration, microbial protein synthesis, and the balance of nitrogen compounds of cattle fed high concentrate diet (80 % dry matter (DM) basis) with two different levels of starch. Eight crossbred beef steers fitted with rumen cannula were assigned to two simultaneous 4?×?4 Latin squares arranged in a 4?×?2 factorial design. Two different starch levels (23 and 38 % of DM) were assigned to each Latin square, independently. Within each Latin square, four treatments were randomly assigned to the experimental animals (control; monensin; 1-g yeast [1 g/100 kg body weight (BW)/day] treatment; and 2.5-g yeast [2.5 g/100 kg BW/day] treatment). Feed additives did not influence ruminal pH (P?>?0.05). Total ruminal volatile fatty acids (VFA) concentration was greater (P?<?0.05) in the diet with the lowest starch level. Similarly, monensin and 1-g yeast treatments resulted in greater (P?<?0.05) VFA concentration in the rumen. Monensin inclusion in the diet with the highest starch level led to a decrease (P?<?0.05) in lactate concentration in the rumen. However, acetate levels were increased (P?<?0.05) by the inclusion of 1 g of yeast in the diet with lowest starch level. Ruminal concentrations of propionate and butyrate, and ammonia-N were not influenced (P?>?0.05) by none of the additives evaluated. However, propionate concentration was greater (P?<?0.05) in the low-starch diets. Low-starch diets resulted in lower ruminal ammonia-N concentration and greater neutral detergent fiber digestibility (P?<?0.05). The excretion of urinary nitrogenous compounds, purine derivatives, synthesis of microbial protein, microbial efficiency, and balance of nitrogenous compounds were not affected by treatments evaluated (P?>?0.05). Monensin or yeast inclusion in high concentrate beef cattle diets in tropical regions as in Brazil is not justified by do not alter nutrient digestibility, nitrogen balance, and main ruminal parameters.  相似文献   
996.
DNA fingerprinting was used to study the population genetics and paternity of the Rasa Aragonesa sheep (Ovis aries). Using a combination of Hae III and the M13 derived probe pV47, the mean number of bands per individual (5.422 +/- 0.309), the background band sharing coefficient (0.347), the mean population frequency of alleles (0.192) and the mean heterozygosity for bands (0.893) were calculated for 45 individuals from eight different farms in Aragon, northern Spain. Therefore, the estimated probability of missing a wrong paternity was 0.126 for unrelated males, and this probability was 0.438 for full-sibs males. In addition, in a field trial of this technique, paternity was assigned for three ewe-lamb pairs with a probability of 97 per cent in two cases and 77 per cent in one case.  相似文献   
997.
We developed a flow‐limited physiologically based pharmacokinetic model for residues of monensin in chickens and evaluated its predictive ability by comparing it with an external data set describing concentration decays after the end of treatment. One advantage of this model is that the values for most parameters (34 of 38) were taken directly from the literature or from field data (for growth and feed intake). Our model included growth (changes in body weight) to describe exposure throughout the life of the chicken. We carried out a local sensitivity analysis to evaluate the relative importance of model parameters on model outputs and revealed the predominant influence of 19 parameters (including three estimated ones): seven pharmacokinetic parameters, five physiological parameters and seven animal performance parameters. Our model estimated the relative bioavailability of monensin as feed additive at 3.9%, which is even lower than the absolute bioavailability in solution (29.91%). Our model can be used for extrapolations of farming conditions, such as monensin supplementation or building lighting programme (which may have a significant impact for short half‐life molecules such as monensin). This validated PBPK model may also be useful for interspecies extrapolations or withdrawal period calculations for modified dosage regimens.  相似文献   
998.
999.
1000.
Horses are hosts to a wide variety of helminthes; the most important are the cyathostomin, or small strongyles. The viability of a fungal formulation (pellets) using the nematode-trapping fungus Monacrosporium thaumasium was assessed in biological control of horse cyathostomin. Two groups (fungus-treated and control) consisted of six mares in each group, crossbred (ages of 2.5 and 3.5 years), were placed in pastures of Cynodon sp. naturally infected with horse cyathostomin larvae. In the treated group, each animal received 1g/10 kg body weight (0.2g/10 kg live weight of fungus) of pellets of sodium alginate matrix containing the fungus M. thaumasium orally, twice a week for 6 months. In the control group, animals received (1g/10 kg body weight) of pellets without fungus. The egg count per gram of feces showed difference (p<0.01) in the animals treated with the fungus in relation to the control animals during all months of the experiment. The EPG percentage decrease were 87.5%, 89.7%, 68.3%, 58.7%, 52.5% and 35.2% during June, July, August, September, October and November, respectively. In faecal cultures, there was difference (p<0.05) among animals treated with fungus was found in relation to the control animals during all the experiment month, with percentage reduction of 67.5%, 61.4% and 31.8% in September, October and November, respectively. Difference (p<0.01) was observed in the recovery of infective larvae from pastures that were collected up to 20 cm from the dung pats in pastures in the group treated with the fungus in relation to the control group with a reduction of 60.9% and between 0-20 and 0-40 cm from the faecal pat reduction (p<0.01) was about 56% in the group treated with the fungus M. thaumasium in relation to the control group pasture. There was no difference (p>0.05) between the average weight gains in both animal groups. The treatment of horses with pellets containing the nematophagous fungus M. thaumasium can be effective in controlling cyathostomin in the tropical region of southeastern Brazil.  相似文献   
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