Intergenerational effects of birth weight on glucose tolerance and reproductive performance

Women who were themselves small-for-gestational age (SGA) are at a greater risk of adulthood diseases such as non-insulin-dependent diabetes mellitus (NIDDM), and twice at risk of having an SGA baby themselves. The aim of this study was to examine the intergenerational pig. Low (L) and normal (N) birth weight female piglets were followed throughout their first pregnancy (generation 1 (0)). After they had given birth, the growth and development of the lightest (I) and heaviest (n) female piglet from each litter were monitored until approximately 5 months of age (generation 2 (G2)). A glucose tolerance test (GTT) was conducted on G1 pig at similar to 6 months of age and again during late pregnancy; a GTT was also conducted on G2 pigs at similar to 4 months of age. G1 L offspring exhibited impaired glucose metabolism in later life compared to their G1 N sibling but in the next generation a similar scenario was only observed between I and n offspring born to G1 L mothers. Despite G1 L mothers showing greater glucose intolerance in late pregnancy and a decreased litter size, average piglet birth weight was reduced and there was also a large variation in litter weight; this suggests that they were, to some extent, prioritising their nutrient intake towards themselves rather than promoting their reproductive performance. There were numerous relationships between body shape at birth and glucose curve characteristics in later life, which can, to some extent, be used to predict neonatal outcome. In conclusion, intergenerational effects are partly seen in the pig. It is likely that some of the intergenerational influences may be masked due to the pig being a litter-bearing species.

Influence of birth weight on gene regulators of lipid metabolism and utilization in subcutaneous adipose tissue and skeletal muscle of neonatal pigs.

Epidemiological studies suggest that low-birth weight infants show poor neonatal growth and increased susceptibility to metabolic syndrome, in particular, obesity and diabetes. Adipose tissue development is regulated by many genes, including members of the peroxisome proliferator-activated receptor (PPAR) and the fatty acid-binding protein (FABP) families. The aim of this study was to determine the influence of birth weight on key adipose and skeletal muscle tissue regulating genes. Piglets from 11 litters were ranked according to birth weight and 3 from each litter assigned to small, normal, or large-birth weight groups. Tissue samples were collected on day 7 or 14. Plasma metabolite concentrations and the expression of PPARG2, PPARA, FABP3, and FABP4 genes were determined in subcutaneous adipose tissue and skeletal muscle. Adipocyte number and area were determined histologically. Expression of FABP3 and 4 was significantly reduced in small and large, compared with normal, piglets in adipose tissue on day 7 and in skeletal muscle on day 14. On day 7, PPARA and PPARG2 were significantly reduced in adipose tissue from small and large piglets. Adipose tissue from small piglets contained more adipocytes than normal or large piglets. Birth weight had no effect on adipose tissue and skeletal muscle lipid content. Low-birth weight is associated with tissue-specific and time-dependent effects on lipid-regulating genes as well as morphological changes in adipose tissue. It remains to be seen whether these developmental changes alter an individual's susceptibility to metabolic syndrome.

Resource defense polygyny shifts to female defense polygyny over the course of the reproductive season of a Neotropical harvestman

Although studies classify the polygynous mating system of a given species into female defense polygyny (FDP) or resource defense polygyny (RDP), the boundary between these two categories is often slight. Males of some species may even shift between these two types of polygyny in response to temporal variation in social and environmental conditions. Here, we examine the mating system of the Neotropical harvestman Acutisoma proximum and, in order to assess if mate acquisition in males corresponds to FDP or RDP, we tested four contrasting predictions derived from the mating system theory. At the beginning of the reproductive season, males fight with other males for the possession of territories on the vegetation where females will later oviposit, as expected in RDP. Females present a marked preference for specific host plant species, and males establish their territories in areas where these host plants are specially abundant, which is also expected in RDP. Later in the reproductive season, males reduce their patrolling activity and focus on defending individual females that are ovipositing inside their territories, as what occurs in FDP. This is the first described case of an arachnid that exhibits a shift in mating system over the reproductive season, revealing that we should be cautious when defining the mating system of a species based on few observations concentrated in a brief period.

Influence of the season of year, stage of lactation and milking time on the chloride content in bovine milk

From January to October 1995, chloride content determinations were accomplished in 2,218 samples of milk collected from 67 quarters of 17 lactating cows, in initial, middle and final stages of lactation, in the morning and afternoon milking. The highest means of chloride contents were observed among the milk samples collected in the final stage of lactation (0,203 gC1/100ml), in the summer (0,212 gC1/100ml) and in the morning milking (0,189 g C1/100ml). The differences observed between the chloride contents in the samples obtained in the different stages of lactation and the seasons of the year were statistically significant (P<0.0001). The gratest occornce of chloride at rates superior to 0.22 gC1100ml was observed in the final stge of lactation (31.4%), summer (44.2%) and after the morning milking (27.8%). These results evidentiate the influence of physiological and external factors (stage of lactation and season of the year) on the concentration of chloride of milk.

Effects of the season of the year, truck type and location on truck on skin bruises and meat quality in pigs

The purpose of this study was to evaluate the effect of the season of the year (summer vs winter), type of truck (A: single decker vs B : double-decker) and pig location on the truck (front, middle, rear) on the incidence of skin bruising and pork quality variation. For this purpose, 2660 gilts of an average weight of 126.7 (+/- 6.6) kg originating from 19 different farms were used. No interaction between season of the year, type of truck and location on truck was observed. A higher number of bruises on the body at unloading and slaughter (P < 0.0001) and a higher number of bruises on the carcass (P < 0.01) were observed in winter. At unloading a higher number of bruises on the body and on the carcass after slaughter was observed in pigs transported on Truck A (P=0.004 and P=0.05). A higher, although not significant, number of bruises was found on the body of pigs transported in the rear compartment of both trucks. Higher paleness value was found in the longissimus and semimembranosus muscles in summer (P=0.0001) than in winter. Cold and heat stress have a negative influence on skin bruises and meat quality, respectively. Poor vehicle design increases the incidence of bruised carcasses without detracting from pork quality regardless of the climate conditions tested and location of the animal it] the truck. (c) 2006 Elsevier B.V. All rights reserved.

Genetic and environmental factors affecting ultrasound measures of longissimus muscle area and backfat thickness in Nelore cattle

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparison of non-linear growth models to describe the growth curve in West African Dwarf sheep

The objectives of this study were to compare the goodness of fit of four non-linear growth models, i.e. Brody, Gompertz, Logistic and Von Bertalanffy, in West African Dwarf (WAD) sheep. A total of 5274 monthly weight records from birth up to 180 days of age from 889 lambs, collected during 2001 to 2004 in Betecoucou breeding farm in Benin were used. In the preliminary analysis, the General Linear Model Procedure of the Statistical Analysis Systems Institute was applied to the dataset to identify the significant effects of the sex of lamb (male and female), type of birth (single and twin), season of birth (rainy season and dry season), parity of dam (1, 2 and 3) and year of birth (2001, 2002, 2003 and 2004) on the observed birth weight and monthly weight up to 6 months of age. The models parameters (A, B and k), coefficient of determination (112), mean square error (MSE) were calculated using language of technical computing package Matlab(R), 2006. The mean values of A, B and k were substituted into each model to calculate the corresponding Akaike's Information Criterion (AIC). Among the four growth functions, the Brody model has been selected for its accuracy of fit according to the higher R(2), lower MSE and A/C Finally, the parameters A, B and k were adjusted in Matlab(R) 2006 for the sex of lamb, year of birth, season of birth, birth type and the parity of ewe, providing a specific slope of the Brody growth curve. The results of this study suggest that Brody model can be useful for WAD sheep breeding in Betecoucou farm conditions through growth monitoring.

Spatial variability of soil penetration resistance influenced by season of sampling

O objetivo deste trabalho foi analizar a distribuição espacial da compactação do solo e a influência da umidade do solo na resistência à penetração. Esta última variável foi descrita pelo índice de cone. O solo estudado foi Nitossolo e os dados de índice de cone foram obtidos usando um penetrômetro. A resistência do solo foi avaliada a 5 profundidades diferentes, 0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm e mais de 40 cm, porém o conteúdo de umidade do solo foi medido a 0-20 cm e 20-40 cm. As condições hídricas do solo variaram nas diferentes amostragems. Os coeficientes de variação para o índice de cone foram 16,5% a 45,8% e os do conteúdo de umidade do solo variaram entre 8,96% e 21,38%. Os resultados sugeriram elevada correlação entre a resistência do solo, estimada pelo índice de cone e a profundidade do solo. Sem embargo, a relação esperada com a umidade do solo não foi apreciada. Observou-se dependência espacial em 31 de 35 séries de dados de índice de cone e umidade do solo. Esta dependência foi ajustada por modelos exponenciais com efeito pepita variável de 0 a 90% o valor do patamar. em séries de dados o comportamento foi aleatório. Portanto, a técnica das distâncias inversas foi utilizada para cartografar a distribuição das variáveis que não tiveram estrutura espacial. Na krigagem constatou-se uma suavização dos mapas comparados com esses das distâncias inversas. A krigagem indicadora foi utilizada para cartografar a variabilidade espacial do índice de cone e recomendar melhor manejo do solo.

Population structure and breeding season of the South Atlantic hermit crab, Loxopagurus loxochelis (Anomura, Diogenidae) from the Ubatuba region, Brazil

A population of Loxopagurus loxochelis was studied in terms of seasonal abundance, size frequency distribution, sex ratio, and reproductive period (percentage of ovigerous females). Specimens were collected monthly over a period of two years (from September 1995 to August 1997) in the non-consolidated areas of the Ubatuba, Mar Virado, and Ubatumirim bays (northern coast of São Paulo State, Brazil) with a double-rig trawl net. A total of 1,084 individuals were analysed. Animal size (minimum, maximum, and mean +/- SD shield length) was 2.8, 9.1, and 6.88 +/- 1.13 mm for 625 males; 2.8, 8.2, and 5.78 +/- 0.98 mm for 236 non-ovigerous females; and 4.6, 8.0, and 6.24 +/- 0.68 mm for 223 ovigerous females, respectively. Sexual dimorphism was recorded by the presence of males in the largest size classes. The sex ratio was 1.4 : 1 in favour of males. The highest incidence of ovigerous females occurred during winter and spring (June to October), with a low percentage in summer and fall (November to May), indicating continuity in the reproductive cycle. This strategy of reproduction is related to temperature. The occurrence of L. loxochelis in the Ubatuba region represents the final point of northern distribution of this species as a function of water mass influence, and could be its real limit on the Atlantic coast of South America.

Breeding season of the hermit crab petrochirus diogenes (anomura : diogenidae) in the north coast of São Paulo state, Brazil

Petrochirus diogenes, one of the largest hermit crabs in the western Atlantic, was studied in the north coast of the State of São Paulo, Brazil, to determine its breeding season through the analysis of gonad development at a macroscopic level. The analysis of 999 crabs collected from 1995 to 1999, based on four categories of gonad development, showed that males present gonads in the advanced stage during all seasons, and although females present developed ovaries all year as well, the peak incidence is in the summer. The peak of recruitment occurs in the winter.

Comparative gas exchange performance during the wet season of three Brazilian Styrax species under habitat conditions of cerrado vegetation types differing in soil water availability and crown density

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