Efeito de dois sistemas de resfriamento sobre os hormônios tireoidianos e as variáveis termofisiológicas de matrizes suínas em lactação / Effect of two cooling systems on thyroid hormones and thermophysiological variables of lactating sows

Avaliaram-se os efeitos do sistema de resfriamento evaporativo com pressão negativa (SRE) e aspersão de água sobre o telhado (AAT), as variáveis termofisiológicas, os hormônios tireoidianos e a relação neutrófilo:linfócito (N:L) em porcas. Utilizaram-se 61 fêmeas em lactação, que foram divididas nos dois ambientes térmicos, sendo 30 em SRE e 31 em AAT, no verão. A temperatura e a umidade do ar, a frequência respiratória (FR), as temperaturas de superfície (TS) e retal (TR), a concentração de tiroxina e de tri-iodotironina, o número de neutrófilos e linfócitos e a relação N:L foram determinados. A temperatura ambiente pela manhã foi menor em SRE que em AAT (22,1ºC vs. 23,5ºC) e pela tarde (24,8ºC vs. 28,0ºC). Em ambos os períodos, a FR, a TS e a TR foram menores em SRE (de manhã 49 resp.min-1, 31,1ºC e 38,5ºC, respectivamente, e à tarde 55 resp.min-1, 30,3ºC e 38,8ºC, respectivamente) que em AAT (de manhã 54 resp.min-1, 32,8ºC e 38,6ºC, respectivamente; e à tarde 65 resp.min-1, 31,4ºC e 39,1ºC, respectivamente). Animais sob galpão AAT apresentaram menores concentrações de T4 que animais sob SRE (37,84 vs. 42,22nmol.L-1). Em ambiente tropical, no verão, porcas lactantes de ambos os sistemas mantêm a homeotermia.(AU)

The effects of the evaporative cooling system with negative pressure (ECS) and water spray on the roof (WSR) on physiological variables, thyroid hormones and neutrophil/lymphocyte ratio (N:L) in lactating sows were evaluated. Sixty-one lactating females were divided in the two thermal environments, being 30 in SRE and 31 in the AAT shed in the summer. The air temperature and humidity, respiratory frequency (RF), surface temperatures (ST) and rectal (RT), serum thyroxine and triiodothyronine concentration, number of neutrophils and lymphocytes and the N/L ratio were determined. In the afternoon, the matrices in ECS (Tar: 25.0°C and THI: 74.7) and WSR (Tar: 27.6°C and THI: 77.3) were exposed to heat stress. In the morning, RF, ST and RT were lower in ECS (49 breaths.min -1 , 31.1°C and 38.5°C, respectively) than WSR (54 breaths.min -1 , 32.8°C and 38.6°C) and also in the afternoon ECS (55 breaths.min -1 , 30.3°C and 38.8°C, respectively) and WSR (65 breaths.min -1 , 31.4°C and 39.1°C, respectively). Animals under WSR shed presented lower concentrations of T4 than animals under ECS (37.84 vs 42.22nmol.L -1 ). In a tropical environment, in the summer, lactating sows of both systems maintain homeothermia.(AU)

Comparison of moulting methods for layers: high-zinc diet versus fasting.

The serum biochemical profiles, thyroid hormones, body weights and the production and quality of eggs subsequent to moulting, were compared in laying hens subjected to conventional forced moulting or forced moulting with a diet high in zinc. A total of 200 Dekalb White laying hens in their second production cycle were studied. Blood sampling was conducted in a factorial experimental design (2 × 3) with two methods of moulting (fasting or zinc) and three sampling periods (pre-moult, moult and subsequent peak). Total egg protein content, including globulins, was greater with the zinc diet, whereas egg weight and albumen percentage were greater after fasting. The zinc method resulted in an increased shell thickness and calcium percentage but lower percentage of phosphorus. During the moulting period, the hens in the zinc group had heavier mean body weights. It was concluded that moulting with a high-zinc diet could replace fasting, without negative effects on body weight, biochemical variables or subsequent egg quality and production. The zinc method was also better for the birds' welfare.

The influence of low birth weight body proportionality and postnatal weight gain on anthropometric measures of 8-year-old children: a cohort study in Northeast Brazil.

BACKGROUND/OBJECTIVES: Low birth weight (LBW) and rapid postnatal weight gain are associated with future high body adiposity; however, the cumulative effect of LBW and postnatal weight gain remains unclear. The aim of this study was to investigate the influence of body proportionality of LBW infants and postnatal weight gain on body mass index (BMI) and waist circumference (WC) of 8-year-old children. SUBJECTS/METHODS: A nested cross-sectional study was conducted in a cohort of children followed from birth to 6 months and reassessed at 8 years of age. The sample consisted of 167 children born at full term (67 with LBW and 100 with appropriate birth weight). Stunted LBW was defined as length <-2 z-score and wasted LBW as length ⩾ -2 z- score and Ponderal Index <2.5. Rapid growth was defined as weight gain greater than 0.67 s.d. score from birth to 6 months. Multivariate linear regression analysis was used to investigate the net effect of LBW and postnatal weight gain on BMI and WC, controlled for sex, total breastfeeding, socioeconomic status and maternal nutrition. RESULTS: The stunted and wasted LBW contributed significantly to the reduction of BMI and WC, and together explained 10% of the variation of these measurements. Rapid weight gain in the first 6 months of life, shorter total breastfeeding duration, higher socioeconomic status and maternal BMI significantly explained the increase in child BMI and WC. CONCLUSIONS: It was concluded that LBW led to lower body measurements, whereas rapid postnatal weight gain determined higher BMI and WC among school age children.

Desempenho e características bioquímicas de leitões submetidos a dietas com aditivos probióticos, prebióticos, simbióticos e antibióticos / Performance and biochemical parameters of piglets and the use of alternative additives as antibiotic replacement

Avaliaram-se o desempenho e as características bioquímicas de leitões desmamados, utilizando-se aditivos alternativos em substituição aos antibióticos. Foram utilizados 480 leitões machos, distribuídos em delineamento inteiramente ao acaso, composto por cinco tratamentos. A ração foi à base de milho, farelo de soja e um núcleo comercial para leitões. Os tratamentos consistiram em T1: ração sem aditivos, T2: dieta basal com antibiótico, T3: dieta basal com adição de prebiótico, T4: dieta basal com adição de probiótico e T5: dieta basal com adição de simbiótico. Foram avaliados peso corporal, ganho de peso, consumo de ração e conversão alimentar. Em 50 amostras de sangue de leitões, sendo 10 amostras de cada tratamento, avaliaram-se as concentrações séricas de proteínas totais, de albumina e globulina, a relação albumina:globulina e a fosfatase alcalina, creatinina, alanina aminotransferase, aspartato aminotransferase, gama- glutamiltransferase, colesterol, ureia, cálcio e fósforo e a relação cálcio:fósforo. A substituição de antibióticos por aditivos alternativos não influenciou o desempenho nem as características bioquímicas dos leitões.

The experiment was conducted to evaluate the performance and biochemical parameters in weaned piglets using alternative supplements to replace antibiotics. A total of 480 male pigs were used, randomly distributed in delineation with five treatments. The feed was based on corn, soybean meal and a commercial core for piglets. The treatments were T1: diet without supplements or basal diet, T2: basal diet with antibiotics, T3: basal diet with added probiotic, T4: basal diet with added probiotic and T5: basal diet with addition of symbiotic. In the experiment we evaluated performance characteristics, body weight, weight gain, feed intake and feed conversion. In the second part of the experiment, we evaluated the biochemical parameters of piglets used in the first experiment, fifty blood samples, ten samples of each treatment, were taken, and after separation of the clot, the serum was frozen at -20°C. Subsequently we analyzed the serum levels of total protein, albumin, globulin, albumin/globulin, ALP, creatinine, alanine aminotransferase, aspartate aminotransferase, gamma glutamyltransferase, cholesterol, urea, calcium, phosphorus and calcium/phosphorus ratio. No significant differences in biochemical parameters or in the performance of piglets submitted to different diets were found.