Efficiency of prebiotics and probiotics on the performance, yield, meat quality and presence of Salmonella spp in carcasses of free-range broiler chickens

Two trials were carried out in the present study. Trial I evaluated the performance, carcass yield and breast meat quality, whereas Trial II evaluated the efficacy of utilizing prebiotics + probiotics on the control of Salmonella spp incidence in the carcasses of free-range broilers. In Trial I, 688 one-day-old male chicks of the Naked Neck Label Rouge strain were used, distributed in a randomized block design arranged according to a 2 x 2 factorial: control diet or diet supplemented with probiotics and prebiotics; and two rearing systems (confined or with access to paddocks - 3m²/bird), using four replicates with 35 birds each. The birds were reared until 84 days of age following the recommendations of management and nutrition for free-range strains, and had access to paddocks after 35 days of age. Water and food were given inside the experimental poultry house. Birds fed probiotics and prebiotics in the diet and the confined birds showed better performance, carcass yield and meat quality compared to the birds of the other treatments. In Trial II, 128 one-day-old male chicks of the free-range Naked Neck Label Rouge strain were used. The birds were distributed into four treatments: NCC (non-challenged control), NCS (non-challenged supplemented), CC (challenged control) and CS (challenged supplemented). There were no significant effects of adding probiotics and prebiotics in the diet in regard to Salmonella enteritidis recovery from the carcasses.

Testicular thermoregulation in Bos indicus, crossbred and Bos taurus bulls: relationship with scrotal, testicular vascular cone and testicular morphology, and effects on semen quality and sperm production

Mechanisms of testicular thermoregulation, the relationship of scrotal, testicular vascular cone (TVC), and testicular morphology with thermoregulatory capability, and their effects on semen quality and sperm production were studied in 20 Bos indicus, 28 crossbred, and 26 Bos taurus bulls. The ratio of testicular artery length and volume to testicular volume were larger (P < 0.05) in B. indicus and crossbred bulls than in B. taurus bulls (1.03 and 0.94 cm/cm(2). versus 0.48 cm/cm(3); 0.034 and 0.047 ml/cm(3) versus 0.017 ml/cm(3), respectively). Testicular artery wall thickness (average 192.5, 229.0, and 290.0 mum, respectively) and arterial-venous blood distance in the TVC (average 330.5, 373.7, and 609.4 pm, respectively) were smallest in B. indicus, intermediary in crossbred, and greatest in B. taurus bulls (P < 0.05); the proximity between arterial and venous blood was consistent with the estimated decrease in arterial blood temperature after passage through the TVC (5.9, 5.0, and 2.9 degreesC, in B. indicus, crossbred, and B. taurus bulls, respectively). In crossbred and B. taurus bulls, there was a positive top-to-bottom scrotal temperature gradient and a negative testicular subtunic temperature gradient. However, in B. indicus bulls, both scrotal and testicular subtunic temperatures gradients were positive. Differences in the vascular arrangement, characteristics of the artery (e.g. wall thickness) or thickness of the tunica albuginea may have affected the testicular arterial blood and subtunic temperatures in B. indicus bulls. Better testicular thermoregulatory capability was associated with increased scrotal shape (pendulosity), testicular artery length and volume, and top-to-bottom gradient of the distance between the artery wall and the veins in the TVC. Increased semen quality was associated with increased testicular volume and scrotal subcutaneous (SQT) temperature gradient, and with decreased scrotal surface and testicular temperatures. Increased sperm production was associated with increased testicular artery volume, testicular volume, and SQT temperature gradient, and with decreased testicular artery wall thickness, scrotal circumference (SC), and scrotal surface, testicular subtunic, and epididymal temperatures. In conclusion, morphology of the TVC may contribute to the greater resistance of B. indicus bulls to high ambient temperatures by conferring a better testicular blood supply and by facilitating heat transfer between the testicular artery and veins. Testicular thermoregulation was associated with opposing scrotal and testicular subtunic temperatures gradients only in crossbred and B. taurus bulls. Scrotal, TVC, and testicular morphology influence testicular thermoregulatory capability and were associated with differences in semen quality and sperm production. (C) 2003 Elsevier B.V. All rights reserved.

Rat epididymal sperm quantity, quality, and transit time after guanethidine-induced sympathectomy

Guanethidine, a chemical that selectively abolishes peripheral noradrenergic nerves, was used to investigate the role of sympathetic innervation in the maintenance of epididymal sperm quantity and quality. Four groups of 10 adult male rats each were treated daily for 21 days, by i.p. injections, with either 0 (saline vehicle), 6.25, 12.5, or 25 mg/kg guanethidine. Norepinephrine content was reduced to undetectable levels in the cauda epididymidis in all guanethidine groups after 3 wk of treatment and was reduced to 7.4% of the control values after 1 wk of 6.25 mg/kg treatment. While body weight gain was significantly decreased at 12.5 and 25 mg/kg compared to that in controls, there was a significant increase in the weights of the seminal vesicles/coagulating glands in all treated groups. The number of homogenization-resistant spermatids per testis and the daily sperm production per testis remained unchanged. The weight of the epididymis was significantly increased at 6.25 and 12.5 mg/kg. Moreover, the number of cauda epididymal sperm and the transit time were increased significantly at 6.25 mg/kg (10.2 days) compared to values in the control cauda (6.3 days). Neither serum testosterone levels nor LH was affected in a dosage-related manner. There were no effects of guanethidine treatment on cauda epididymal sperm motility or morphology. A quantitative analysis of detergent-extracted cauda epididymal sperm proteins by SDS-PAGE revealed no differences, but there were diminutions in seven proteins in homogenates of caput/ corpus tissue. Histologic analysis of testis and epididymis sections revealed no differences between control and denervated animals. In a subsequent experiment the lowest effective dosage (6.25 mg/kg) was given to rats for 1 wk, and an increased number of cauda epididymal sperm and a delay in sperm transit were observed. Our results indicate that low-dosage guanethidine exposure denervates the epididymis within 1 wk, thereby delaying epididymal transit; however, neither 1- nor 3-wk exposure produces qualitative changes in the sperm.

Impairment on sperm quality and fertility of adult rats after antiandrogen exposure during prepuberty

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of fertilization in water quality and in zooplankton community in open plankton-culture ponds

The effect of swine manure fertilization on the water quality of zooplankton artificial culture in two ponds was measured in diel cycles on different months (October 1999, January and March 2000). Fertilization affected directly water quality; values for total phosphorus were above 1.4 mgL(-1) and maximum rates for ammonia reached 108 mu gL(-1). Zooplankton community comprised four species, namely, Brachionus calyciflorus, B. falcatus, Moina sp. and Thermocyclops sp. B. falcatus (Rotifera) and Moina sp (Cladocera) were dominant respectively in January and in March. There was no difference in abundance of zooplankton between the two ponds (p>0.05), although adult cyclopoid Thermocyclops sp was different between diel cycles (p<0.05). There were significant differences (p<0.05) in dissolved oxygen, ammonia, total phosphorus, orthophosphate, nitrite and nitrate between ponds. In fact, only dissolved oxygen and pH were significantly different (p<0.05) between the ponds' surface and bottom. Organic fertilization also provided greater amount of nutrients and higher pH and conductivity, coupled to greater oscillations in the concentration of dissolved oxygen, directly affecting the zooplanktonic composition.

Physiological quality and enzymatic activity of crambe seeds after the accelerated aging test

O crambe é uma cultura promissora para produção de biodiesel, principalmente pelo alto conteúdo de óleo de suas sementes. No entanto, não há metodologias estabelecidas para avaliar a qualidade fisiológica das sementes desta espécie e lotes não podem ser comparados, especialmente por testes de vigor, como o de envelhecimento acelerado. O objetivo da presente pesquisa foi avaliar o efeito da alta temperatura e do período de exposição durante o teste de envelhecimento acelerado na qualidade fisiológica e atividade enzimática de sementes de crambe. Dois lotes de sementes de crambe, cultivar Brilhante, foram analisados por meio dos testes de teor de água, massa de 1.000 sementes, germinação, primeira contagem, condutividade elétrica, atividade enzimática (peroxidase e superóxido dismutase) e comprimento de plântulas. As avaliações foram conduzidas antes e após o envelhecimento acelerado, que foram testadas diferentes temperaturas (38, 40 e 42ºC) e períodos de exposição (24, 48 e 72h). O delineamento experimental foi o inteiramente casualizado com quatro repetições. Os dados foram submetidos à análise de variância e as médias foram comparadas pelo teste de Tukey (p < 0.05). O teste de Dunnet (p < 0.05) foi utilizado para comparar os valores da testemunha (antes do envelhecimento acelerado) com cada valor médio individualmente. O teste de correlação linear simples também foi aplicado. Conclui-se que a interação temperatura x período de exposição afeta a qualidade fisiológica das sementes e a atividade enzimática e que as melhores condições durante o teste de envelhecimento acelerado são dependentes do genótipo.

Technological quality and utilization of potato tubers

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Performance, carcass traits, meat quality and economic analysis of feedlot of young bulls fed oilseeds with and without supplementation of vitamin E

The objective of this research was to evaluate average daily gain (ADG), carcass traits, meat tenderness and profitability of keeping cattle fed different oilseeds and vitamin E in feedlot. A total of 40 Red Norte young bulls with initial average body weight of 339±15 kg were utilized. The experimental design was completely randomized in a 2 × 2 factorial arrangement. The experiment lasted 84 days and experimental diets presented soybeans or cottonseeds as lipid sources associated or not to daily supplementation of 2,500 UI vitamin E per animal. The concentrate:roughage ratio was 60:40. Diets had the same amount of nitrogen (13% CP) and ether extract (6.5%). The data were analyzed by means of statistical software SAS 9.1. Neither vitamin supplementation nor lipid source affected ADG. There was no interaction between lipid source and vitamin supplementation for the variables studied. The inclusion of cottonseed reduced the carcass yield. There was no effect of diets on hot and cold carcass weights or prime cuts. The inclusion of cottonseed reduced the backfat thickness. No effect of experimental diets on the rib-eye area was observed. There was no effect of lipid source or vitamin supplementation on meat tenderness, which was affected, however, by ageing time. Diets with soybeans presented higher cost per animal. The utilization of soybean implied reduction of the gross margin (R$ 59.17 and R$ 60.51 for diets based on soy with and without supplemental vitamin, respectively, vs. R$ 176.42 and R$ 131.79 for diets based on cottonseed). The utilization of cottonseed enables improvement of profitability of feedlot fattening, in spite of negatively affecting some carcass characteristics.

Relation between quality and rheological properties of lactic beverages

The physicochemical (pH, fat and total solids content), sensory (appearance, consistency and taste), and rheological characteristics of five different commercial brands of lactic beverages were determined. Rheological measurements were obtained at 5 degreesC and 25 degreesC using a Brookfield rheometer. The experimental data were described by the power law and Herschel-Bulkley models. The ANOVA of the results were conducted using an incomplete block design, and using Tukey test. Samples showed a significant difference (P less than or equal to 0.05%) for fat content and pH. There was a significant difference in total solids content only among Nestle (A), Batavo (C), and Parmalat (D) samples. Sensory evaluation showed more global acceptability for Nestle; however, Nestle and Vigor (E) lactic beverages obtained better results for appearance than for consistency and taste. Batavo obtained the best score for taste. All test samples exhibited non-Newtonian behavior, with thixotropy. Upward curves showed pseudoplastic behavior, while downward curves showed dilatant behavior with the exception of the Nestle sample, at 25 degreesC. Lactic beverages from all brands analyzed showed similar rheological behavior. (C) 2001 Elsevier B.V. Ltd. All rights reserved.

Effects of egg storage time on spread of hatch, chick quality, and chick juvenile growth

A total of 1,800 incubating eggs produced by a commercial flock of Cobb broiler breeders was used to determine the effects of storage duration (3 or 18 d) on spread of hatch and chick quality. Chick relative growth (RG) at the end of 7 d of rearing was also determined as a measure of the chick performance. Chick quality was defined to encompass several qualitative characteristics and scored according to their importance. Eggs stored for 3 d hatched earlier than those stored for 18 d (P < 0.05). Hatching was normally distributed in both categories of eggs, and the spread of hatch was not affected by storage time (P = 0.69). Storage duration of 18 d reduced the percentage of day-old chick with high quality as well as average chick quality score (P < 0.05). RG varied with length of egg storage, quality of day-old chick, and the incubation duration (P < 0.05). Eighteen-day storage of eggs not only resulted in longer incubation duration and lower quality score but also depressed RG. Chick quality as defined in this study was correlated to RG and storage time. It was concluded that day-old chick quality may be a relatively good indicator of broiler performance. The results suggest however that in order to improve performance prediction power of chick quality, it would be better to define it as a combination of several qualitative aspects of the day-old chick and the juvenile growth to 7 d.

Influence of used frying oil quality and natural tocopherol content on oxidative stability of fried potatoes

Sunflower oil (SO) and high-oleic sunflower oil (HOSO) were used to prepare fried potatoes by either discontinuous or continuous laboratory frying. Fried potatoes that had been fried in oils of differing quality were stored at 60 degrees C for up to 30 d and evaluated for polar compounds, polymers, peroxide value, oil stability index, and alpha-tocopherol content. Results obtained through the various methods applied were consistent and indicated that the length of the induction period could not be explained only on the basis of the degree of unsaturation or polar compound levels in fried potatoes before storage. alpha-Tocopherol content also had a significant influence as potatoes fried in HOSO, with 16% polar compounds and only 10 mg/kg alpha-tocopherol at the starting point of storage, were oxidized more rapidly than potatoes fried in SO with a comparatively higher degradation level, 19% polar compounds, and 100 mg/kg alpha-tocopherol.

The relationship between diet quality and basal metabolic rate in endotherms: Insights from intraspecific analysis

In this article, we review intraspecific studies of basal metabolic rate (BMR) that address the correlation between diet quality and BMR. The food-habit hypothesis stands as one of the most striking and often-mentioned interspecific patterns to emerge from studies of endothermic energetics. Our main emphasis is the explicit empirical comparison of predictions derived from interspecific studies with data gathered from within-species studies in order to explore the mechanisms and functional significance of the putative adaptive responses encapsulated by the food-habit hypothesis. We suggest that, in addition to concentrating on the relationship among diet quality, internal morphology, and BMR, new studies should also attempt to unravel alternative mechanisms that shape the interaction between diet and BMR, such as enzymatic plasticity, and the use of energy-saving mechanisms, such as torpor. Another avenue for future study is the measurement of the effects of diet quality on other components of the energy budget, such as maximum thermogenic and sustainable metabolic rates. It is possible that the effects of diet quality operate on such components rather than directly on BMR, which might then push or pull along changes in these traits. Results from intraspecific studies suggest that the factors responsible for the association between diet and BMR at an ecological timescale might not be the same as those that promoted the evolution of this correlation. Further analyses should consider how much of a role the proximate and ultimate processes have played in the evolution of BMR.