Desenvolvimento ponderal e parâmetros hematológicos e bioquímicos de cordeiros Pantaneiros submetidos a diferentes manejos de amamentação / [Ponderal development and hematological and biochemical parameters of Pantaneiro lambs subjected to different suckling regimens]

Este estudo teve por objetivo avaliar o desenvolvimento ponderal e a dinâmica dos parâmetros hematológicos e bioquímicos de cordeiros Pantaneiros submetidos a diferentes manejos de amamentação dos 15 aos 43 dias. Foram separados 30 cordeiros em três diferentes grupos (n=10). Os grupos foram caracterizados conforme o tempo de permanência das ovelhas com suas crias em diferentes sistemas de amamentação: MAM24 - ovelhas e cordeiros 24 horas em conjunto; MAM12 - ovelhas e cordeiros 12 horas em conjunto durante a noite; MAM2x30 - ovelhas e cordeiros 30 minutos de manhã e 30 minutos à tarde em conjunto. As coletas de amostras sanguíneas e as pesagens ocorriam a cada sete dias. Houve aumento significativo no peso com o avanço da idade dos cordeiros nos três manejos, mas os tratamentos não diferiram entre si para o ganho de peso. Houve diferenças entre os três tratamentos para a variável hematológica CHGM e para as variáveis bioquímicas AST, glicose, ureia e proteína total. As variáveis bioquímicas foram influenciadas pela faixa etária dos animais. Os diferentes manejos de amamentação não influenciaram o desenvolvimento ponderal dos cordeiros. Não ocorreram alterações patológicas. Alguns parâmetros hematológicos e bioquímicos podem ser influenciados pelo desenvolvimento etário dos cordeiros.(AU)

This study aimed to evaluate the weight development and the dynamics of hematological and biochemical parameters of Pantaneiro lambs submitted to different breastfeeding management from 15 to 43 days. First, 30 lambs were separated into three different groups (n = 10). The groups were characterized according to the length of stay of ewes with their young in different breastfeeding systems: MAM24 - ewes and lambs 24 hours together. MAM12- Sheep and lambs 12 hours together at night. MAM2x30 - sheep and lambs 30 minutes in the morning and 30 minutes in the afternoon together. Blood samples were collected and weighed every seven days. Significant increase in weight was observed with the age of the lambs in the three managements, but the treatments did not differ for weight gain. Differences were identified between the three treatments for the hematological variable CHGM and for the biochemical variables AST, glucose, urea and total protein. Correlating the age of the lambs with the biochemical variables, there was variation influenced by the age of the animals. The different management of breastfeeding did not influence the weight development of the lambs. Hematological and biochemical variations did not represent pathological changes. Some hematological and biochemical parameters may be influenced by the age development of lambs.(AU)

Soro do leite em substituição ao leite na cria de bezerros / Use of whey in substitution to milk in holstein calves / Suero de leche en sustitución a la leche en cría de terneros

O uso de leite na alimentação de bezerras representa o maior custo na fase de cria. Com o objetivo de avaliar a viabilidade técnica da utilização de diferentes quantidades de dieta líquida na alimentação de bezerros da Raça Holandês, utilizou-se 160 ou 240 litros de dieta líquida, durante um período de 53 dias (do quarto ao 56o dia de vida) de aleitamento com diferentes níveis de inclusão de soro de leite em substituição ao leite integral (0, 10 e 20%), em esquema fatorial 2x3 (160 ou 240 litros de dieta líquida e 0, 10 ou 20% de inclusão de soro do leite), conduzido no Laboratório de Bovinocultura Leiteira da Universidade Federal de Santa Maria. Os animais foram distribuídos inteiramente ao acaso em seis tratamentos, com quatro repetições por tratamento. Foram avaliados o consumo de matéria seca do concentrado (CMSC), da matéria seca total (CMST), ganho médio diário (GMD), conversão alimentar (CA), peso vivo final (PVF) e o comportamento dos animais. Para os níveis de soro do leite, ocorreu uma resposta quadrática (p<0,05) para o CMSC, CMST, GMD e CA. Os bezerros que receberam 160 litros de leite apresentaram maior (p<0,05) CMSC, porém pior CA. O CMST, o GMD e o PVF foram superiores (p<0,05) para os bezerros que consumiram 240 litros de leite durante o período experimental, com melhor CA para esse grupo de animais. Na análise do comportamento não foi determinada diferença significativa para os parâmetros avaliados (p>0,05).(AU)

The use of milk in the calves feed represents the largest cost in the calf production system. The aim was to evaluate the technical feasibility of using different amounts of liquid diet in feeding of Holstein calves. It was used 160 or 240 liters of milk during 53 days (from the fourth to the 56th day of life) of feeding with different levels of milk serum included to whole milk (0, 10 and 20%), in a factorial 2x3 model conducted at the Dairy Cattle Laboratory of the Federal University of Santa Maria. The animals were randomly assigned to six treatments with four replicates per treatment. The dry matter intake of concentrate (DMIC), of the total dry matter (TDM), average daily gain (ADG), feed conversion (FC), final body weight (FBW) and the behavior of animals. For milk serum levels, there was a quadratic response (p<0.05) for the DMIC, TDM, ADG and FC. DMIC and FC were higher (p<0.05) for calves received 160 liters of milk. The ADG, TDM and FBW were higher for calves that consumed 240 liters of milk during the experimental period, while FC was lower (p<0.05) for this group of calves. There was no difference in the behavior of calves for the evaluated parameters (p>0.05).(AU)

El uso de leche en la alimentación de terneros representa el costo más grande en la fase de creación. Con el fin de evaluar la viabilidad técnica de utilizar diferentes cantidades de dieta líquida en la alimentación de terneros de la raza holandesa, se utilizaron 160 o 240 litros de dieta líquida por un período de 53 días (desde el cuarto hasta el día 56º día de vida), alimentación con diferentes niveles de adición de suero de leche entera (0, 10 y 20%), en un estudio factorial 2x3 (160 0 240 litros de dieta líquida y 0, 10 o 20% de inclusión de suero de leche), llevado a cabo en el Laboratorio de Ganado Lechero de la Universidad Federal de Santa María. Los animales se distribuyeron completamente al azar en seis tratamientos con cuatro repeticiones por tratamiento. Se evaluó el consumo de materia seca del concentrado (CMSC), de la materia seca total (CMST), ganancia media diaria (GMD), conversión alimenticia (CA), el peso vivo final (PVF) y el comportamiento de los animales. Para los niveles de suero de leche, hubo una respuesta cuadrática (p<0,05) para el CMSC, CMST, GMD y CA. Los terneros que recibieron 160 litros de la leche presentaron mayor (p<0,05) CMSC, sin embargo con peor CA. Las variables CMST, GMD y PVF fueran mayores (p<0,05) para los terneros que consumieron 240 litros de leche durante el período experimental, mientras con mejor CA para ese grupo de animales. En el análisis del comportamiento no ha sido determinada diferencia significativa para los parámetros evaluados (p>0,05).(AU)

Diferentes fontes de ferro na prevenção da anemia ferropriva e no desempenho de leitões lactentes / Different sources of iron for the prevention of iron deficiency anemia and performance of suckling piglets

Com o objetivo de avaliar o uso de diferentes fontes de ferro na prevenção da anemia ferropriva e no desempenho em leitões lactentes, dividiram-se 202 leitões em cinco tratamentos: FD - aplicação intramuscular de 200mg de ferro dextrano no terceiro dia de idade; T24 - terra à vontade fornecida aos leitões a cada 24 horas do terceiro ao 19º dia; T48 - terra à vontade fornecida aos leitões a cada 24 horas do terceiro ao 10º dia e do 11º ao 19º dia, com intervalo de 48 horas; T72 - terra à vontade fornecida aos leitões a cada 24 horas do terceiro ao 10º dia e do 11º ao 19º dia, com intervalo de 72 horas; SA - suplemento alimentar ultraprecoce rico em ferro quelatado em pó (SAUP) fornecido do terceiro ao 11º dia, com intervalo de 48 horas. O ferro dextrano aplicado no terceiro dia de vida e a suplementação com terra e SAUP foram eficientes para garantir o desempenho de leitões no período de aleitamento e não influenciaram no consumo de ração nem na taxa de viabilidade. As diferentes fontes de ferro estudadas não influenciaram o leucograma e foram eficientes na prevenção da anemia ferropriva e no desempenho dos leitões lactentes. Com relação às concentrações de hemoglobina e hematócrito, os animais suplementados com ferro dextrano apresentaram valores superiores quando comparados aos que recebem terra e SAUP.(AU)

In order to evaluate the use of different sources of iron to prevent iron deficiency anemia and to appraise the performance of suckling piglets, we sorted 202 piglets in five treatments. ID - intramuscular injection of 200mg of iron dextran on the third day of age; T24 - free daily access to land provided to piglets every 24 hours from the third to the nineteenth day; T48 - free daily access to land provided to piglets every 24 hours from the third to the tenth day and from day 11 to day 19 with an interval of 48 hours; T72 - free daily access to land provided to piglets every 24 hours from the third to the tenth day and from day 11 to day 19 with an interval of 72 hours; FS - Food supplement rich in iron-chelating powder (SAUP) available from the third to the eleventh day with an interval of 48 hours. The iron dextran applied on the third day of life as well as the supplementation with land and SAUP were effective to ensure the performance of piglets during the lactation period and did not affect feed intake or the viability rate. The different sources of iron studied did not influence the WBC (White Blood Cell) and succeded in preventing iron deficiency anemia and performance of suckling piglets. Regarding the concentrations of hemoglobin and hematocrit, the animals supplemented with iron dextran showed higher values when compared to those who receive land and SAUP.(AU)

Efeito do aumento da frequência de ordenhas no início da lactação sobre produção, composição do leite e características reprodutivas de vacas mestiças Holandês-Zebu / Effects of increasing milking frequency in early lactation on milk production, milk composition and reproductive parameters of crossbred Holstein Zebu cow

Cinquenta e três vacas mestiças Holandês-Zebu, multíparas, foram distribuídas em quatro grupos para avaliar os efeitos de quatro e duas ordenhas diárias até o 21º dia da lactação, seguidas de duas ordenhas diárias, com ou sem a sucção de leite pelo bezerro, sobre: produção, composição do leite, peso corporal das vacas e dos bezerros e características reprodutivas. A produção e a composição do leite foram avaliadas a cada quatro dias até o 33º dia da lactação e, a partir desta data, a cada 15 dias. Os animais foram pesados ao parto, semanalmente até dois meses após o parto e, a partir desta data a cada 30 dias. O experimento foi desenvolvido em delineamento inteiramente ao acaso, em arranjo fatorial 2x2. As produções médias de leite foram 16,7, 17,2, 19,0 e 18,9kg/d (P<0,01), para vacas ordenhadas duas e quatro vezes com ou sem a sucção de leite pelo bezerro, respectivamente. Os percentuais de gordura, sólidos totais, produção de leite corrigido para 3,5 por cento de gordura e corrigido para sólidos totais foram mais elevados nos grupos com quatro ordenhas. O aumento da frequência de ordenhas no início da lactação aumentou a produção de leite (P<0,01), mas não influenciou o peso dos bezerros e nem as características reprodutivas avaliadas (P>0,05).

Fifty three multiparous crossbred Holstein Zebu cows were distributed in four groups with the purpose of evaluating the effects of four daily milking until lactation day 21 and after this day two milking, with or without suckling by the calf, on milk yield and composition, cows and calves weights and the reproductive parameters. Milk production and composition were measured each four days until the 33th day of lactation, then each 15 days until the end of lactation. The animals were weighed at birth, and weekly until two months postpartum and then each 30 days until the end of lactation. The experiment was completely randomized in a 2x2 factorial design. The average milk productions were 16.7, 17.2, 19.0, and 18.9kg/day (P<0.01), for cows milked twice or four times a day with or without suckling by the calf, respectively. Fat and total solids percentages, 3.5 percent fat corrected milk, and total solids corrected milk were higher in the groups of cows milked four times a day. The increase in milking frequency at the beginning of lactation increased the production of milk (P<0.01), but did not influence the weight of cows and calves or reproductive parameters (P>0.05).

Efeitos da dieta rica em linhaça na lactação sobre a composição corporal e função tireóidea da prole na idade adulta / Effects of maternal flaxseed diet during lactation on body composition and thyroid function in adult animals

A Linhaça (Linum Usitatissimum) apresenta diversas substâncias com alegados efeitos benéficos que favorecem a diminuição da adiposidade, glicemia e melhoram o perfil lipidêmico e o sistema cardiovascular. Neste trabalho, investigamos na prole 21 e 180 dias de vida o efeito do consumo materno da semente de linhaça durante a lactação sobre os parâmetros associados a composição corporal, a homeostase glicêmica, lipídica e protéica, a leptinemia, adiponectinemia e insulinemia, a função tireoideana e a via de sinalização da leptina no eixo hipotálamo-hipófise-tireóide. As ratas lactantes foram separadas em dois grupos: controle (C) - recebendo ração a base de caseína (20%) e linhaça (L) - recebendo ração adicionada de 25% da semente de linhaça, contendo 18,9% de proteína (sendo 13,9% de caseína e 5% de linhaça) durante a lactação. O sacrifício das proles ocorreu aos 21 e 180 dias de idade, para determinação de: glicemia, albuminemia, proteínas totais, hematócrito, hemoglobina, colesterol total e triglicerídeos, insulina, leptina, adiponectina, TSH, T4 livre e T3 total. Os animais foram completamente eviscerados para obtenção da carcaça e análise da composição corporal. O consumo alimentar e a massa corporal (MC) foram aferidos diariamente durante a lactação e de 4 em 4 dias após a lactação até a idade adulta. As ratas lactantes do grupo L não apresentaram diferença na massa corporal e consumo alimentar. Durante a lactação a prole L apresentou maior ganho de peso corporal e após ao desmame observamos um aumento transitório de massa corporal até a idade adulta. Aos 21 dias, observamos na prole do grupo L menor gordura total e subcutanea, colesterol total, triblicerideo, albumina, insulina, T3 total e atividade de D1 no fígado; e aumento da área dos adipocitos no tecido subcutaneo, leptina, TSH e expressão de Ob-R, STAT3 e p-STAT3 na hipofise (p<0,05). Aos 180 dias, o grupo L apresentou menor glicemia, adiponectina, T4 livre, atividade de D1 e D2 na tireóide...

Flaxseed (Linum usitatissimum) presents high number of substances with alleged beneficial effects that decrease the adiposity, glocuse levels and improved lipid profile and cardiovascular system. In this study, we investigated in the offspring at 21 and 180 days old the effect of maternal consumption of flaxseed during lactation on the parameters associated with body composition, glucose homeostasis, lipid and protein, leptinemia, adiponectinemia and insulinemia, thyroid function, and leptin signaling pathway in the hypothalamus-pituitary-thyroid axis in the offspring at 21 and 180 days old. Lactating rats were divided into: (1) Controls (C), diet containing 20% casein; (2) FLaxseed (F), diet with additional 25% of flaxseed, containing 18.9% protein (13.9% from casein and 5% from flaxseed). The offspring were sacrificed at 21 and 180 days of age to determinate: glycemia, albumin, leptin, adiponectin, TSH, free T4 and total T3. The animals were completely eviscerated to obtain the carcass by body composition analysis. The maternal food intake and body mass were measured daily during the lactation, and after weaning were monitored once every 4 days until they were 180 days old. The dams of F group presented no changes in body mass and food intake. During the lactation the F offspring showed higher body mass and after weaning they presented a higher transitory body mass until 180 days old. At 21 days old, F group showed lower total and subcutaneous fat mass, total cholesterol, triacylglycerol, albumin, insulin, total T3 and D1 liver activity; and higher subcutaneous adipocytes area, leptin, TSH and Ob-R, STAT3 and p-STAT expression in pituitary (p<0,05). At 180 days old, F group presented lower glycemia, adiponectin, free T4 and D1 and D2 activity in thyroid; and higher visceral and subcutaneous adipocytes area, insuli, Ob-R expression in thyroid and D2 activity in brown adipose tissue (p<0,05). In conclusion, maternal flaxseed diet during lactation...

Efecto de sistemas de crianza (leche de cabra vs. sustitutivo lácteo) y sexo en cabritos de raza florida sobre su crecimiento y características de la canal / Effect of sex and feed (maternal milk vs. milk substitute) on the growth and carcass characteristics in florida goat kids

Para evaluar el efecto de sistemas de crianza (leche de cabra vs. sustituto lácteo) sobre el crecimiento y las características de la canal de cabritos lactantes, fueron utilizados 64 cabritos de la raza Florida, nacidos el mismo día y procedentes de partos dobles de un rebaño comercial, bajo sistema semiextensivo y ubicado en la provincia de Sevilla, España. El primer día permanecieron lactando con sus madres y después se dividieron en dos grupos: LN (lactancia natural) y LA (lactancia artificial con lactorreemplazante). El crecimiento de los animales se controló durante los primeros 60 días de vida, edad con la que se sacrificaron, valorando las principales características de la canal. Los resultados indican que la velocidad de crecimiento fue más alta en el grupo LN (203 g/día vs. 187 g/día) y significativamente mayor (P<0,05) en los machos (202 g/día vs. 184 g/día). El sexo influyó significativamente (P<0,05) en la mayor parte de los componentes del “quinto cuarto” (caídos, despojos rojos y depósitos grasos), mientras que el sistema de crianza solo lo hizo sobre los depósitos grasos. Las canales de los machos fueron más largas, profundas y compactas que las de las hembras (P<0,05), en tanto que la alimentación sólo influyó significativamente (P<0,05) en los índices de compacidad, L/G, G/F y Th/G. Las canales pesaron entre 7,2 y 8,2 kg, y los rendimientos de la canal se situaron en el intervalo 52-56 por ciento, con diferencias significativas (P<0,05) entre sexos y sistema de crianza. El despiece de la canal ofreció valores del 32-33 por ciento para la pierna, 26-27 por ciento para el costillar, 19-20 por ciento para la espalda, 12-13 por ciento para el pecho y 9-10 por ciento para el cuello, sin diferencia significativa (P>0,05) entre sistema de crianza y sexo. Las canales de los machos presentaron mayor (P<0,05) porcentaje de músculo (58,4 vs. 57,1 por ciento), y de hueso (22,7 vs. 21,8 por ciento) y menor de grasa...

The experiment was conducted on a commercial farm, under semiextensive system and located in the province of Seville, Spain. In order to evaluate the effect of the type of food (goat milk vs. substitute) and sex on the growth and carcass traits, sixty four twins kids of Florida goat breed born the same day were used. The animals remained with their mothers the first day of life. Afterwards, they were divided into two groups: LN (goat milk) and LA (milk replacer). The daily weight gain was higher in LN (203 g/d vs. 187 g/d) and significantly greater (P<0.05) in males (202 g/d vs. 184 g/d). Sex significantly influenced (P<0.05) most of the components of the “fifth quarter”, whereas the food type had an effect on the fat deposit. The carcass of the males were longer, deeper and more compact than those of the females (P<0.05), whereas the food type only had a significant effect (P<0.05) in the indices of compactness, L/G, G/F and Th/G. The carcass weighed between 7.2 and 8.2 kg, and the carcass yields were 52-56 percent, with significant differences (P<0.05) between genders and type of food. The quartering of the carcass offered values of the 32-33 percent for legs, 26-27 percent for ribs, 19-20 percent for the back, 12-13 percent for chest and 9-10 percent for the neck, without statistical difference (P>0.05) between type of food and sex. The carcass of the males displayed higher (P<0.05) percentage of muscle (58.4 vs. 57.1 percent), and of bone (22.7 vs. 21.8 percent) and lower percentage of fat (17.9 vs. 19.9 percent) as compared to females, whereas the food type only affected significantly the intermuscular fat content (12.2 percent LN vs. 11.1 percent LA).

Cambios en el peso corporal durante la lactancia de vacas B. taurus x B. indicus en un sistema de doble propósito en el trópico mexicano / Changes in body weight during the lactation of B. taurus x B. indicus cows in a dual-purpose in the mexican tropics

El objetivo de este estudio fue evaluar los cambios de peso corporal (PC) durante la lactancia de vacas Holstein x Cebú (HC) y Suizo x Cebú (SC) en un sistema de doble propósito en el bosque tropical húmedo de México. Vacas de tres hatos comerciales se pesaron al parto y cada mes hasta el secado. Los datos comprendieron 3.356 pesajes de 234 vacas tomados durante los años de 2002 a 2005. Un análisis preliminar, no mostró diferencias entre grupos genéticos, por lo tanto, los datos se analizaron según el número de parto (1; 2; 3 y 4 o más partos), utilizando modelos mixtos para medidas repetidas. Los modelos incluyeron los efectos fijos de hato, año de parto y mes de medición y los efectos aleatorios de vaca y residual. La gráfica de PC de las vacas mostró un ligero incremento continuo en las primeras dos lactancias y una tendencia a mantenerse constante en los grupos de vacas con 3 y 4 o más partos. El peso al parto (PP) y el promedio de todos los pesos de una vaca durante la lactación (PVL) incrementaron con el número de parto. El peso adulto de las vacas se alcanzó en la tercera lactancia. Los coeficientes de correlación de los PC de una misma lactancia para los cuatro grupos de parto fluctuaron de 0,51 a 0,89 (P<0,05).

The objective of this study was to evaluate the body weight (BW) changes during lactation of Holstein x Zebu and Brown Swiss x Zebu cows in a dual-purpose system in the forest humid tropics of Mexico. Cows from three commercial herds were weighed at calving and every month until drying. Data included 3.356 measurements from 234 cows, during the years of 2002 to 2005. Repeated measures data were analysed by parity number (1, 2, 3 and 4 or more calvings) using mixed model procedures, which included the fixed effects of herd, year of calving, month of measure, and the random effects of cow and residual. The depicted graphic of the BWs showed a continuous slight increase in the first two lactations and a trend to keep their BW constant in the group of cows with 3 or 4 or more lactations. BW at calving (BWC) and the average of all BW during the lactation for a cow (ABW) increased with parity. The adult BW of the cows was reached at the third lactation. The correlation coefficients between the BWs of a given lactation for the four group of parity ranged from 0.51 to 0.89 (P<0.05).

Ethanol Intake during Lactation Alters Milk Nutrient Composition and Growth and Mineral Status of Rat Pups

Lactating Wistar rats were fed a liquid diet containing either ethanol [ethanol-fed group (EFG)] or an isocaloric amount of carbohydrate [pair-fed group (PFG)] from day 1 postpartum up to day 14 of lactation, to investigate micro/macronutrient milk composition and the mineral status of pups. EFG presented a reduction of daily milk production and milk composition was significantly higher in protein and lower in carbohydrate, while the lipid content was similar to that of PFG. When compared to PFG, the milk of EFG had a decreased proportion of C22:6 n-3 fatty acid and an increase in medium-chain fatty acids and of several minerals. Pups of EFG showed reduced growth and a lower concentration of Cu and Sr in plasma and lower concentrations of Ca, P and Cl, and higher concentrations of Cd in the brain. We conclude that maternal EtOH intake greatly impairs lactational performance and modifies the mineral status of pups.

Efecto del peso de sacrificio y sexo sobre la canal de corderos lactantes del cruce Suffolk Down x Merino Precoz Alemán / Effect of slaugther weight and sex on the carcass of Suffolk Down x German Merino Precocious suckling lambs

Se estudio el efecto del peso vivo al sacrificio y del sexo sobre las características de la canal del cordero lactante del cruce Suffolk Down x Merino Precoz Alemán. Las variables cuantificadas fueron: peso canal caliente (PCC), longitud de la canal (LC), rendimiento comercial (RC) y verdadero (RV), área del Longissimus dorsi (ADL), espesor de grasa dorsal (EGD), peso componentes corporales (PCCO), y rendimiento al trozado comercial (RTC). Se utilizaron 30 corderos (15 machos y 15 hembras) sacrificados a 2 pesos vivos: 10 kg (7 machos y 7 hembras) y 15 kg (8 machos y 8 hembras). Los resultados se analizaron considerando los dos pesos de sacrificio (10 y 15 kg), sexo y la interacción entre ellos. El PCC, LC, ALD y EGD fueron superiores en los animales sacrificados a los 15 kg (P<0,05). Se observó una tendencia hacia un mayor RTC para los cortes pierna, espalda y chuletas, aunque no se observó ningún efecto significativo de los considerados, ni por la interacción (P<0,05). Considerando los resultados obtenidos se puede afirmar que el cruce Suffolk Down x Merino Precoz Alemán, sacrificado a un peso vivo de 10 y 15 kg, presenta excelentes características para la producción de carne.

The carcasses of thirty suckling lambs (Suffolk Down x German Merino Precocius) were studied to estimate the effect of sex and slaughter weight on: hot carcass weight, carcass length, commercial and true dressing percentages, ribeye area, dorsal fat thickness, body components weight, and retail yield. The results were analysed considering two slaughter weights (10 and 15 kg), sex, and their interaction. Hot carcass weight, carcass length, ribeye area, and dorsal fat thickness were affected by slaughter weight. Leg, shoulder, and chops, showed the highest commercial yields and were not affected by sex, slaughter weight, nor their interaction. Based on these results it can be said that this genotype has excellent qualities for meat production.

Thyroid function in post-weaning rats whose dams were fed a low-protein diet during suckling

This study was designed to evaluate the thyroid and pituitary hormone levels in post-weaning rats whose dams were fed a low-protein diet during suckling (21 days). The dams and pups were divided into 2 groups:a control group fed a diet containing 22 per cent protein that supplies the necessary amount of protein for the rat and is the usual content of protein in most commercial rat chow, and a diet group fed a lowprotein (8 per cent) diet in which the protein was substituted by an isocaloric amount of starch. After weaning all dams and pups received the 22 per cent protein diet. Two hours before sacrifice of pups aged 21, 30 and 60 days, a tracer dose (0.6 mui) ofl25I was injected (ip) into each animal. Blood and thyroid glands of pups were collected for the determination of serum T4, T3 and TSH and radioiodine uptake. Low protein diet caused a slight decrease in radioiodine uptake at 21 days, and a significant decrease in T3 levels (l28 ñ 14 vs 74 ñ 9 ng/dl, P<0.05), while T4 levels did not change and TSH was increased slightly. At 30 days, T3 and TSH did not change while there was a significant increase in both T4 levels (4.8 ñ 0.3 vs 6.1 ñ 0.2 mug/dl, P<0.05) and in radioiodine uptake levels (0.34 ñ 0.02 vs 0.50 ñ 0.030 per cent/mg thyroid, P<0.05). At 60 days serum T3, T4 and TSH levels were normal, but radioiodine uptake was still significantly increased (0.33 ñ 0.02 vs 0.41 ñ 0.03 per cent/mg thyroid, P<0.05). Thus, it seems that protein malnutrition of the dams during suckling causes hypothyroidism in the pups at 21 days that has a compensatory mechanism increasing thyroid function after refeeding with a 22 per cent protein diet. The radioiodine uptake still remained altered at 60 days, when all the hormonal serum levels returned to the normal values, suggesting a permanent change in the thyroid function.

Efeito da ingestäo de álcool durante a lactaçäo sobre a produçäo e composiçäo do leite materno e sobre o crescimento da prole: estudo em ratas / Effect of alcohol ingestion during lactation on milk production and composition and on progeny's growth: study in rats

Foi verificada a possibilidade da ingestäo materna de álcool durante a lactaçäo, de alterar a composiçäo, a produçäo do leite e o crescimento neonatal. Para tal, ratas lactantes que recebem 20 por cento de etanol e respectivas proles (AL) foram comparadas com controles (C). Todos os animais foram sacrificados no 12§ dia da lactaçäo. Nas ratas AL, a ingestäo de alimentos diminuiu, determinando uma reduçäo significativa do peso corporal em comparaçäo com os controles. A ingestäo alcoólica durante a lactaçäo ocasionou diminuiçäo do volume de produçäo do leite; a composiçäo foi significativamente menor em carboidratos, enquanto o conteúdo protéico e lipídico do leite näo diferiram dos valores de animais controles. A prole de mäes alcoolizadas apresentou retardo de crescimento e evidente desnutriçäo em comparaçäo aos controles. Demonstra-se que o consumo de álcool durante a lactaçäo altera a produçäo e composiçäo do leite, comprometendo o crescimento e o desenvolvimento normal da cria.

Effect of vitamin D supplementation in lactating rats on the neonatal growth.

In lactating rats consuming a commercial diet adequate in calcium, phosphorus and vitamin D, the effect of supplementation of 3000 IU and 7,500 IU of vitamin D3 on the lactational performance of the dams and soft tissue and skeletal growth in the pups has been investigated. On 28th day of age, the pups in the supplemented groups were significantly heavier than in the control group. Study of the indices of cellular growth in the liver and gastrocnemius muscle revealed that the increase in the soft tissue weight was due to a significant increase in protein, RNA and DNA contents (cellular hyperplasia) without any change in protein/DNA ratio (cell size). In the tibia, compared to controls, the dry bone weight and ash weight were more in the supplemented groups, but ash weight/dry bone weight ratio was not altered. The improvement in the neonatal growth was most probably due to the greater milk yield observed in the dams in supplemented groups and not due to any anabolic effect in the pups since direct administration of 500 IU or 1,000 IU of vitamin D3 in 10 day old pups did not increase their body weight.

Maternal nutrition and development of intestinal functions: II--Effect of feeding high protein and high fat diets to lactating rats.

Effects of feeding high-protein (HP) and high-fat (HF) diets to lactating rats have been studied on the development of microvillus membrane enzymes and glycosylation in suckling rats. The activities of sucrase and lactase were significantly (P less than 0.01) decreased in the pups reared on HP fed dams. Alkaline phosphatase (AP), leucine aminopeptidase (LAP) and gamma-glutamyl-transpeptidase (gamma-GTP) activities were essentially similar in HP and pair-fed groups. Pups reared on dams fed HF-diet, revealed nearly a 20% increase in disaccharidase levels and a significant (P less than 0.05) decrease in AP activity compared to the pair-fed controls. The activities of LAP and GTP were unaffected under these conditions. Sialic acid content was unaltered, however, fucose level of the membranes was significantly reduced in pups nursed by mothers fed HP-(P less than 0.05) or HF-(P less than 0.01) diet. The binding of 125I-labelled wheat germ agglutinin and Ulex europeus agglutinin was in agreement to the data on sialic acid and fucose contents of the membranes. The binding of peanut agglutinin to microvillus membranes was enhanced by 31% and 21% in HP and HF groups, respectively. These findings suggest that the quality of maternal nutrition affects the enzymes and glycosylation of brush-borders in developing rat intestine.

Effect of ethanol intake during lactation on the metabolism of dams and pup development

Ethanol intake during lactation causes growth deficiency and decreased plasma and liver protein content in pups. The lipid content of pup liver and brain was similar to that of the control group. Mammary gland protein content decreased, but the rate of lipogenesis in this gland was increased. This fact may be relevant to an adequate supply of lipid substrate to the pups