Behavioral meaningful opioidergic stimulation activates kappa receptor gene expression

The periaqueductal gray (PAG) has been reported to be a location for opioid regulation of pain and a potential site for behavioral selection in females. Opioid-mediated behavioral and physiological responses differ according to the activity of opioid receptor subtypes. The present study investigated the effects of the peripheral injection of the kappa-opioid receptor agonist U69593 into the dorsal subcutaneous region of animals on maternal behavior and on Oprk1 gene activity in the PAG of female rats. Female Wistar rats weighing 200-250 g at the beginning of the study were randomly divided into 2 groups for maternal behavior and gene expression experiments. On day 5, pups were removed at 7:00 am and placed in another home cage that was distant from their mother. Thirty minutes after removing the pups, the dams were treated with U69593 (0.15 mg/kg, sc) or 0.9% saline (up to 1 mL/kg) and after 30 min were evaluated in the maternal behavior test. Latencies in seconds for pup retrieval, grouping, crouching, and full maternal behavior were scored. The results showed that U69593 administration inhibited maternal behavior (P < 0.05) because a lower percentage of kappa group dams showed retrieval of first pup, retrieving all pups, grouping, crouching and displaying full maternal behavior compared to the saline group. Opioid gene expression was evaluated using real-time reverse-transcription polymerase chain reaction (RT-PCR). A single injection of U69593 increased Oprk1 PAG expression in both virgin (P < 0.05) and lactating female rats (P < 0.01), with no significant effect on Oprm1 or Oprd1 gene activity. Thus, the expression of kappa-opioid receptors in the PAG may be modulated by single opioid receptor stimulation and behavioral meaningful opioidergic transmission in the adult female might occur simultaneously to specific changes in gene expression of kappa-opioid receptor subtype. This is yet another alert for the complex role of the opioid ...

Avaliação da persistência na lactação da raça Guzerá, utilizando modelos de regressão aleatória / Evaluation of lactation persistency of Guzerat cows using random regression models

Estimaram-se a herdabilidade e as correlações genéticas e de ambiente permanente entre seis medidas de persistência da lactação de vacas da raça Guzerá, utilizando modelo de regressão aleatória. Foram considerados 8276 registros de produção de leite no dia do controle, na primeira lactação, de 1021 vacas. A regressão aleatória foi calculada pela função logarítmica de Ali e Schaeffer e pelo polinômio de Legendre, obtendo-se os coeficientes para os efeitos fixos, genético aditivo e de ambiente permanente. A função que mais se adequou aos dados foi a de Ali e Schaeffer, mas apresentou problemas de convergência. Os resultados evidenciaram que a persistência é uma característica com herdabilidade de valor moderado e de baixa correlação com o valor genético para produção de leite aos 305 dias, indicando a possibilidade de se obter resposta à seleção para mudança na curva de lactação sem afetar negativamente a produção total de leite na lactação. A medida de persistência que calcula a diferença de produção de leite entre as fases intermediária e inicial da lactação apresentou alta correlação com a produção aos 305 dias.

The heritability and the genetic and permanent environment correlations were estimated among six different measures of persistency in the lactation of Guzerat cow, using the Random Regression Model. A total of 8,403 records from 1,034 first lactation cows were evaluated. The Random Regression Model was calculated by the logarithmic function of Ali and Schaeffer and Legendre polynomials to get coefficients for fixed, additive genetic and permanent environment effects. Ali and Schaeffer was the function that better fit to the data, but it had convergence problems. The results showed that persistence is a trait with moderate heritability, and low correlation with genetic value for 305-d milk production which allows to select animals in order to alter the format of the curve of production without affecting the total productivity. The measure of persistence that calculates the difference of milk production between the medium and initial phases was highly correlated with 305-d milk production.

Estimates of correlations among yield traits and somatic cell score with different models to adjust for bovine somatotropin effects on Holstein dairy cows

Records of Holstein cows from the Dairy Records Processing Center at Raleigh, NC were edited to obtain three data sets: 65,720 first, 50,694 second, and 65,445 later lactations. Correlations among yield traits and somatic cell score were estimated with three different models: 1) bovine somatotropin (bST) administration ignored, 2) bST administration as a fixed effect and 3) administration of bST as part of the contemporary group (herd-year-month-bST). Heritability estimates ranged from 0.13 to 0.17 for milk, 0.12 to 0.20 for fat, 0.14 to 0.16 for protein yields, and 0.08 to 0.09 for somatic cell score. Estimates were less for later than first lactations. Estimates of genetic correlations among yields ranged from 0.35 to 0.85 with no important differences between estimates with the 3 models. Estimates for lactation 2 agreed with estimates for lactation 1. Estimates of genetic correlations for later lactations were generally greater than for lactations 1 and 2 except between milk and protein yields. Estimates of genetic correlations between yields and somatic cell score were mostly negative or small (-0.45 to 0.11). Estimates of environmental correlations among yield traits were similar with all models (0.77 to 0.97). Estimates of environmental correlations between yields and somatic cell score were negative (-0.22 to -0.14). Estimates of phenotypic correlations among yield traits ranged from 0.70 to 0.95. Estimates of phenotypic correlations between yields and somatic cell score were small and negative. For all three data sets and all traits, no important differences in estimates of genetic parameters were found for the two models that adjusted for bST and the model that did not

Impact of bovine somatotropin on ranking for genetic value of dairy sires for milk yield traits and somatic cell score

Records of Holstein cows were used to examine how different models account for the effect of bovine somatotropin (bST) treatment on genetic evaluation of dairy sires for yield traits and somatic cell score. Data set 1 included 65,720 first-lactation records. Set 2 included 50,644 second-lactation records. Set 3 included 45,505 records for lactations three, four and five. Estimated breeding values (EBV) of sires were with three different animal models. With Model 1, bST administration was ignored. With Model 2, bST administration was used as a fixed effect. With Model 3, administration of bST was used to define the contemporary group (herd-year-month of calving-bST). Correlations for EBV of 1,366 sires with treated daughters between pairs of the three models were calculated for milk, fat and protein yields and somatic cell score for the three data sets. Correlations for EBV of sires between pairs of models for all traits ranged from 0.971 to 0.999. Fractions of sires with bST-treated progeny selected in common (top 10 to 15%) were 0.94 and usually greater for all pairs of models for all traits and parities. For this study, the method of statistical adjustment for bST treatment resulted in a negligible effect on genetic evaluations of sires when some daughters were treated with bST and suggests that selection of sires to produce the next generation of sires and cows might not be significantly affected by how the effect of bST is modeled for prediction of breeding values for milk, fat and protein yields and somatic cell score

Association of prolactin gene variants with milk production traits in Russian Red Pied cattle

A total of 125 Russian Red Pied cows were genotyped for the prolactim-related gene. The PRL-RsaI genotypes were analysed using the Polymerase chain reaction -restriction fragment length polymorphism [PCRRFLP] method. In this breed, the frequencies of alleles were as follows; A= 0.794 and B= 0.206. The frequencies of AA, AB and BB genotypes were 0.598, 0.392 and 0.01; respectively. Results showed that: BB genotype had higher milk yield than AA and AB individuals [P < 0.05]. BB genotype showed higher milk fat yield than AA and AB individuals [P < 0.05]. With respect to milk fat content [%], the AB genotype had higher levels than the AA and BB individuals [P < 0.05]. No differences between the cows of different PRL-RsaI genotypes were found in terms of milk fat yield and milk protein concentration. The results showed that the highest milk and milk fat yields were obtained by cows with the genotype PRL-RsaI BB. The results presented here demonstrate that the prolactin gene may be considered as a marker for dairy traits in cattle

Genetic trend for milk yield in Guzerat herds participating in progeny testing and MOET nucleus schemes

Genetic trends for 305-day milk yield (P305) in Brazilian Guzerat herds under selection were compared. Data from 4898 lactations of 3179 purebred and crossbred cows from various regions of Brazil were used. Milk yield was adjusted for mature age and the contemporary groups were defined as herd and calving year. Genetic parameters were estimated using the MTDFREML program. The model included the random effects of animals and permanent environment, and herd-calving year, calving season and genetic composition as fixed effects. Genetic trends were estimated by linear regression of weighted average estimated breeding values as a function of calving year. The average P305 was 2065 ± 922 kg and the heritability was 0.23 ± 0.03. The annual genetic trend in estimated breeding values of cows for P305 was 7.09 ± 0.71 kg between 1987 and 2004, and 6.47 ± 2.35 kg between 1997 and 2004. For cows born and raised in the multiple ovulation and embryo transfer (MOET) nucleus, this trend was 36.46 ± 24.54 kg/year between 1997 and 2004, 183.14 ± 47.94 kg/year between 1997 and 2000, and 9.13 ± 19.19 kg/year between 2001 and 2004. An average inbreeding coefficient of 0.04 was found for inbred MOET cows in 2004. Increasing the size of the family and introducing new progenies changed reliabilities and predicted transmitting ability estimates of MOET sires. In conclusion, there was a positive genetic trend for milk yield in the MOET nucleus at low inbreeding coefficients due to the increased accuracy and estimated genetic merit, but no changes in the average milk yield were observed.

Association of genetic polymorphism in GH gene with milk production traits in Beijing Holstein cows.

Associations were analysed between polymorphisms of the growth hormone gene (GH-MspI) (localized in intron 3) and milk production traits of Beijing Holstein cows (a total of 543 cows). Polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method was used for identification of various genotypes. Frequencies of genotypes were 0.77, 0.21 and 0.02 for A/A, A/B and B/B, respectively. The frequency of the GH A allele is 0.875. The results of the least squares means show that in all three lactations, the GH A/A cows yielded more milk (P less than 0.01 for lactation I and P less than 0.05 for lactations II and III), whereas A/B cows showed higher milk fat content than A/A individuals (P less than 0.05 for lactations I and II, and P less than 0.01 for lactation III). The A/A cows yielded more fat than A/B individuals (P less than 0.01 only in lactation I). The A/A cows yielded more milk protein than A/B individuals (P less than 0.01 for lactations I, II, and III). The A/A cows produced milk of higher protein content than of A/B individuals (P less than 0.05 only in lactation II).

Associação do loco BoLA-DRB3.2 com produção de leite em bovinos da raça Gir / Association of BoLA-DRB3.2 locus with bovine milk production in Gir breed

A associação entre os alelos do loco BoLA-DRB3.2, identificados pela técnica de PCR-RFLP, e a produção de leite na raça Gir foi estudada por meio da análise de dados moleculares e fenotípicos de 424 vacas Gir, utilizando um modelo misto, sob modelo animal. Os dados moleculares consistiam dos genótipos dos animais para os alelos do loco BoLA-DRB3.2 e os dados fenotípicos eram referentes à produção de leite em até 305 dias de lactação. O loco é altamente polimórfico nesta raça, sendo identificados sete alelos (BoLA-DRB3.2*4, *8, *11, *19, *28, *41 e *48) que não haviam sido encontrados em animais zebuínos. Dois alelos (*16 e *29) estavam significativamente associados com maiores produções de leite, sugerindo que o próprio loco BoLA-DRB3.2 ou um QTL a ele ligado influencia a produção de leite de vacas Gir.

Evaluation of crosses of Holstein, Jersey or Brown Swiss sires x Holstein-Friesian/Gir dams. 3. Lifetime performance and economic evaluation

Lifetime dairy production, reproduction and growth traits of 75 females sired by Holstein, Jersey or Brown Swiss bulls and Holstein-Friesian x Gir dams of 1/2 to 3/4 Holstein-Friesian fractions were compared. The animals were in a single herd under the same management. Milk, fat and protein yields, concentrates fed, reproduction, and weights were recorded throughout the lifetime of the cows. The data were analyzed by least squares techniques under models including the fixed effects of breed of sire, Bos taurus fraction and year of birth. Herd lifes for Holstein, Jersey and Brown Swiss crosses were 6.006 +/- 0.812, 8.129 +/- 0.863 and 7.247 +/- 0.777 years. Milk yields per day of herd life were 7.150 +/- 0.266, 6.757 +/- 0.282 and 6.249 +/- 0.254 kg. Weights of cull cows sold were 458 +/- 15, 415 +/- 15 and 457 +/- 13 kg. Based on these and on previously reported results of the same experiment, intakes of roughage and pasture were estimated from energy requirements. Lifetime expenditures on concentrates, roughages, pastures, milking, reproduction, and heifer rearing were calculated based on mean performance of each breed of sire, as well as on receipts from animals and milk sold (the latter with four sets of prices of protein, fat and carrier). The conclusion was that in systems of artificial female calf rearing and male calf wastage, the Jersey crosses appear to offer important economic benefits to farmers, which would be even greater if payment on milk protein and fat becomes effective

Genetic and non-genetic effects on productive and reproductive traits of cows in dual-purpose herds in southeastern Mexico

Data on productive and reproductive performance of cows in dual-purpose herds were analyzed to determine the effect of some environmental and genetic factors on saleable milk yield (SMY), lactation length (LL), daily saleable milk per lactation (DMYL), calving interval (CI), and daily saleable milk per calving interval (MYCI) in dual-purpose herds in Yucatan, Mexico. Repeatabilities (re) for these traits were also estimated. Data were obtained from monthly visits to 162 herds from 1996 to 2000. The fixed factors studied were: region (central, eastern and southern), parity number (1 to 6), calving year (1996 to 2000) and calving season (dry, rainy and windy and rainy), genetic group (low- (< 0.50%), medium- (50%) and high- (> 50%) grade cows with European genes). About 2700 to 7700 cows were evaluated for each trait. All factors had significant effects (P < 0.05) on the traits except for region on CI and calving season on DMYL. The overall means for SMY, LL, DMYL, CI, and MYCI were: 1322.3 +/- 80.5 kg, 224.8 +/- 1.3 days, 5.8 +/- 0.1 kg, 555.1 +/- 16.5 days, and 3.0 +/- 0.1 kg, respectively. The re values for SMY, LL, DMYL, CI, and MYCI traits were: 0.19 +/- 0.03, 0.08 +/- 0.04, 0.16 +/- 0.04, 0.00 +/- 0.08, and 0.08 +/- 0.07, respectively. First parity cows had lower SMY, shorter LL, longer CI, and lower MYCI means than cows with more than one parity. Medium grade cows produced more SMY, DMYL and MYCI and had shorter CI than low- and high-grade cows. Therefore, under Yucatan conditions medium-grade cows should be exploited, and more attention should be given to first parity cows in order to improve the productivity in the herd. The relatively high re estimates for SMY and DMYL can be used to calculate most probable producing abilities, in order to identify which cows should be culled.

Non-coordinate expression of closely linked mouse casein genes.

Expression levels of five mouse casein genes were analysed in the mammary gland of virgin, pregnant and lactating mice. We have already shown that the five murine casein genes are arranged in the order, alpha-beta-gamma-epsilon-kappa in a tandem array, very close to each other in a 250 kb DNA fragment of mouse genome. Northern blot analysis showed that, of the calcium-sensitive casein genes, the epsilon casein gene is expressed only during lactation unlike the alpha, beta and gamma casein genes which are expressed during pregnancy and lactation. Even though the alpha, beta and gamma genes exhibited a co-ordinated expression pattern from mid to the later stages of pregnancy, the mRNA levels varied considerably (60, 90 and 100% respectively) by the onset of lactation. The mRNA level of the calcium-insensitive kappa casein gene increased from mid-pregnancy but at a lower rate and reached approximately 60% by the first day of lactation. Considering the locations and closeness of the casein genes, a non-coordinate expression profile is exhibited by the mouse casein genes, particularly the epsilon casein gene.

Genetic and phenotypic parameters of productivity traits on the first three lactations in Gyr cattle herds

Records of Gyr cows selected for milk production were obtained from the National Gyr Dairy Cattle Breeding Program (Embrapa/CNPGL) and analyzed, in order to estimate genetic parameters for the first three lactations and to verify the effects of some environmental factors on milk production from 1979 to 1994. Genetic parameters were estimated by REML with an animal model and a group of fixed effects that included classes of herd, year, season and age at calving. Milk production means and standard deviations were 2,183 kg, 707 kg; 2,682 kg, 762 kg and 2,638 kg, 851 kg, for first, second, and third lactations, respectively. Heritability estimates were 0.20, 0.12, and 0.19 for first, second, and third lactations, respectively, and repeatability was 0.44. Genetic correlation estimates were: 0.68 between first and second lactations, 0.84 between first and third lactations and 1.0 between second and third lactations. Results confirm other research for specialized dairy breeds and firmly suggest that even in breeds of Indian origin the best time to make selection decisions is during the first lactation.

Análisis genético del cociente producción de leche/perímetro torácico como indicador indirecto de la eficiencia en bovinos Holstein Friesian / Genetic analysis of milk yield/chest girth ratio as an indirect mesure of productive efficiency in Hosltein cows

El objetivo de este trabajo fue estudiar el cociente de producción de leche/perímetro torácico ajustado, considerándolo como un indicador aproximado de la eficiencia productiva lechera (ELA), a fin de incluirlos como criterio de selección en un programa de mejoramiento genético en ganado Holstein; con ese propósito se estimaron las varianzas y covarianzas aditivas utilizando el método de máxima verosimilitud restringida de la producción de leche ajustada a 305 días (PL) y ajustada a 305 días equivalente maduro (PEM), el perímetro torácico constante al momento del parto(PTA), el cociente PL/PTA (ELAAJ) y el cociente PEM/PTA (ELAEM). La heredailidad para PL, PEM, ELAAJ, ELAEM y PTA fue de 0.19 ñ 0.10, 0.27 ñ 0.11, 0.28 ñ 0.11, 0.64 ñ 0.14 y 0.25 ñ 0.11, respectivamente. Se estimaron las correlaciones fenotípicas y genéticas de las que sobresalen las correlaciones entre ELAAJ con PTA (-0.11 ñ 0.04 y -0.50 ñ 0.03), con PL (0.96 ñ 0.04 y 0.67 ñ 0.20) y con PEM (0.94 ñ 0.04 y 0.86 ñ 0.10), y PTA con PL (0.17 ñ 0.04 y 0.27 ñ 0.40). Se observaron valores inferiores en PTA equivalentes a 20 kg d peso vivo menos en el 10 por ciento superior de ELAAJ de las vacas de primer parto. Por ser ELAAJ una medida indirecta de la eficiencia muy simple, se concluye que su inclusión en los programas de selección del ganado Holstein presenta ventajas teóricas en la eficiencia, que aunque pequeñas, pudieran repercutir favorablemente en la economía de la empresa dedicada a la producción de leche

Factores de riesgo en enfermedades alérgicas / Risk factor in allergy diseases

El periodo posnatal inmediato representa para el niño una etapa de alto riesgo para su sensibilización. La expresión del fenotipo alérgico está determinado por las características genéticas, e influenciado por diversos factores, entre ellos la dieta materna (durante el embarazo y la lactancia) el mes de nacimiento, el régimen alimentario del lactante y las infecciones de las vías aéreas, además de otros factores adyuvantes, como el tabaquismo y la contaminación ambiental. La combinación de estos factores en contacto con el sistema inmune, aún inmaduro en el producto, puede propiciar un riesgo elevado de sensibilización y posterioremente manifestarse clínicamente.

Expression of active human erythropoietin in the mammary gland of lactating transgenic mice and rabbits

Transgenic mice and rabbits were generated using a chimeric gene comprising the human erythropoietin (hEPO) cDNA under the 5' and 3' regulatory sequences of the rabbit whey acidic protein gene. Transgenic mice expressed hEPO at levels of 0.01 mg/l in the milk of lactating females showing that the genetic construct was functional. Reverse transcriptase polymerase chain reaction with RNA from various tissues showed that this transgene was expressed mainly in the ovary and mammary gland. In rabbits, we demonstrated the germ line transmission of the transgene. The hEPO was obtained in the milk of lactating females at levels of up to 0.0003 mg/l. Although the expression levels were low, biologically active hEPO was obtained in the milk of transgenic rabbits without any apparent detrimental effect for the animals. In vitro, the specific activity of the rabbit-derived hEPO was higher than that reported for the natural hEPO, thus suggesting differences in the glycosylation pattern in at least part of the molecules secreted by the mammary gland of transgenic rabbits

Fatores genéticos e de ambiente que influenciam os componentes da curva de lactaçäo de bovinos da raça Holandesa / Genetic and environmental factors affecting the lactation curve components of Holstein cattle

Estudaram-se pelo método dos quadrados mínimos 1710 lactaçöes completas de 672 vacas da raça Holandesa, filhas de 75 touros, distribuidas em sete anos. As médias ajustadas para as características produçäo total de leite (PTL), produçäo inicial ascendente (PI), produçäo no pico da lactaçäo (PP) e persistência da lactaçäo (P60) foram 5003,10 ñ 120,54 kg/lactaçäo, 22,53 ñ 0,42 kg/dia, 24,22 ñ 0,41 kg/dia e 2,72 ñ 0,61, respectivamente. As médias observadas de duraçäo da lactaçäo e da fase ascendente foram: 312,52 ñ 50,46 dias e 69,48 ñ 5,98 dias, respectivamente. O ano do parto e a idade da vaca afetaram, significativamente, todas as características estudadas. A estaçäo de pariçäo foi uma importante fonte de variaçäo somente para a PI e P60. Os coeficientes de repetibilidade estimados foram 0,50 ñ 0,03, 0,26 ñ 0,03, 0,33 ñ 0,03 e 0,24 ñ 0,03, para PTL, PI, PP e P60, respectivamente. As herdabilidades foram 0,27 ñ 0,11, 0,17 ñ 0,09, 0,23 ñ 0,10 e 0,13 ñ 0,08, na mesma ordem da citaçäo anterior. As correlaçöes genéticas entre PTL e demais características foram positivas e apresentaram valores moderados. Os coeficientes de herdabilidade estimados para as características estudadas e as correlaçöes genéticas e fenotípicas entre as carcterísticas que compoem a curva de lactaçäo e a PTL indicaram a possibilidade de seleçäo indireta para a PTL utilizando-se, como critério, os componentes da curva

Phosphoglucomutase proteins in human milk

O polimorfismo do loco 4 da fosfoglicomutase foi investigado em uma amostra de colostro obtida de 652 mulheres (60% brancas e 40% negras), coletada 24 a 48 hs. após o parto, em Porto Alegre, Brasil. Uma nova amostra de leite foi obtida de 175 dessas mulheres com cerca de 17 dias de lactaçäo. No colostro observou-se um acentuado desvio no equilíbrio de hardy-Weinberg, havendo em geral um excesso de homozigotos e deficiência de heterozigotos. No leite, no entanto, esse desequilíbrio näo ocorreu. As diferenças entre as duas distribuiçöes säo devidas à detecçäo de padröes nas amostras que näo apresentavam atividade no primeiro período, assim como a variabilidade na ativaçäo enzimática, que pode ocorrer no início da lactaçäo. As frequências gênicas no leite (n = 175) foram: brancos (n = 127) PGM4*1 = 0,20, PGM4*2 = 0,41, PGM4*3 = 0,38, PGM4*4 = 0,01; negróides (n = 48) PGM4*1 = 0,15, PGM4*2 = 0,52, PGM4*3 = 0,32 e PGM4*4 = 0,01