Concentrate: forage ratio in the diet of dairy cows does not alter milk physical attributes     

Sandro Charopen Machado  Concepta Margareth McManus  Marcelo Tempel Stumpf  Vivian Fischer 《Tropical animal health and production》2014,46(5):855-859

This study aimed to evaluate the effect of concentrate-to-forage ratio (C:F) on the performance, blood profile, and milk physicochemical characteristics of mid-lactation cows fed a corn silage-based diet. Twenty four Holstein cows, with BW 575?±?70 kg, body condition score (BCS) 3.1?±?0.2, milk yield 18.4?±?3.0 kg, and days in milk (DIM) 121?±?21 were randomly allocated into three treatments with C:F ratios of 35:65, 45:55, and 55:45 on a dry matter (DM) basis. Data was submitted to analyses of variance and regression. Increasing C:F from 35 to 55 % linearly enhanced milk production (22 to 23.6 kg day^?1) and serum urea nitrogen (16.8 to 19.6 mg/dL), while it linearly reduced lactose and fat in milk (4.8 to 4.6 %; 3.9 to 3.6 %, respectively). Body weight, BCS, milk acidity, ethanol stability, coagulation time, and milk and blood mineral contents did not differ among treatments. During the last period of measurements, increased C:F reduced urinary pH and milk urea nitrogen. Changes of concentrate-to-forage proportion from 35 to 55 % increased milk yield, altered chemical composition without changing BW, BCS, acidity, stability, and mineral content of milk and blood attributes.  相似文献   

The effect of sex and genotype on growth performance,feed efficiency,and carcass traits of local sheep group Pantaneiro and Texel or Santa Inês crossbred finished on feedlot     

Fernando Miranda de Vargas Junior  Charles Ferreira Martins  Guilherme dos Santos Pinto  Marcos Barbosa Ferreira  Hélio de Almeida Ricardo  André Gustavo Leão  Alexandre Rodrigo Mendes Fernandes  Alfredo Teixeira 《Tropical animal health and production》2014,46(5):869-875

This study aimed to assess and compare the growth performance, feed efficiency, and carcass traits of Pantaneiro sheep and their Texel and Santa Inês crossbreds. Ninety-six lambs, fifty-one males, and forty-five females, with a mean weaning weight of 15.21?±?1.25 kg and 78?±?13 days of age, were slaughtered at a 32-kg body weight. The results showed better production efficiency from males compared with females. Texel-crossed lambs had a better growth performance than the other genotypes. The Texel?×?Pantaneiro lambs were more efficient with a better feedlot performance, higher ribeye muscle area, and better carcass characteristics with an adequate amount of fat cover. Pantaneiro lambs and their crosses with meat breeds could be useful in meat production systems under Savanna environmental conditions.  相似文献   

Exploratory analysis of differences in sperm morphology in Nelore and Gir (Bos indicus) bulls     

Aline Costa de Lucio  Antonio Sérgio Ferraudo  Leticia Zoccolaro de Oliveira  Adriana Santana do Carmo  Benner Geraldo Alves  Kele Amaral Alves  Solange Almeida  Luis Alfredo Deragon  William Pereira  Luisa Cunha Carneiro  Vera Fernanda Martins Hossepian de Lima 《Tropical animal health and production》2014,46(5):765-770

The aim of this study was to evaluate the effects of breed and season on semen quality parameters of zebu bulls. Data (1,632 registers) of semen production from Gir (n?=?4) and Nelore (n?=?15) bulls were collected between October 2005 and November 2009. The ejaculates were collected twice a week during various seasons (summer, fall, winter, and spring) and evaluated for the following semen parameters: ejaculate volume, sperm concentration, sperm motility, forward progressive motility (FPM), and sperm morphology. Factor analysis was used to determine the relationship among variables. The effect of breed (Gir and Nelore) and season and their cross effect on each parameter and extracted factor were tested using ANOVA. A negative correlation (P?<?0.05) was observed between FPM and proximal droplet, as well as with abnormal loose head, abnormal small head, pouch formation, abnormal mid-peace, and strongly folded tail. Gir bull sperm showed more major defects, detached acrosome, and minor FPM (P?<?0.01), whereas Nelore bulls showed a higher number of sperm with normally loose head.  相似文献   

Replacement of wheat bran with spineless cactus (Opuntia ficus indica Mill cv Gigante) and urea in the diets of Holstein x Gyr heifers     

Carolina Corrêa de Figueiredo Monteiro  Airon Aparecido Silva de Melo  Marcelo Andrade Ferreira  José Mauricio de Souza Campos  Julyana Sena Rodrigues Souza  Evannielly Thuanny dos Santos Silva  Rafael de Paula Xavier de Andrade  Emmanuelle Cordeiro da Silva 《Tropical animal health and production》2014,46(7):1149-1154

The aim of this study was to evaluate the replacement effect of wheat bran with spineless cactus and urea in heifers. Twenty-four heifers with an average initial weight of 185?±?13 kg were used in this experiment. Four levels of spineless cactus corrected with urea and ammonium sulfate (9:1) were studied: 0, 33, 66, and 100 % replacement with wheat bran. Samples of feed, orts, and feces were analyzed to estimate the intake and digestibility of dry matter (DM) and nutrients. Indigestible neutral detergent fiber was used as an internal marker. The experiment was conducted in a completely randomized design. Dry matter, neutral detergent fiber, and total digestible nutrient intake demonstrated a quadratic effect (P?P?P?相似文献   

Serological survey and risk factors for brucellosis in water buffaloes in the state of Pará, Brazil     

Jenevaldo Barbosa da Silva  Charles Passos Rangel  Adivaldo Henrique da Fonseca  Eziquiel de Morais  Wagner Marcelo Souza Vinhote  Danillo Henrique da Silva Lima  Natália da Silva e Silva  José Diomedes Barbosa 《Tropical animal health and production》2014,46(2):385-389

To evaluate the prevalence and possible risk factors for brucellosis caused by Brucella abortus in water buffaloes in the state of Pará, Brazil, 3,917 female buffalo serum samples from pregnant and non-pregnant animals were examined: 2,809 from Marajó Island and 1,108 from the mainland. The buffered acidified plate antigen (BAPA) screening test positively diagnosed 4.8 % (188/3,917) of the animals with brucellosis, and the 2-mercaptoethanol (2-ME) confirmatory test affirmed 95.7 % (180/188) of the results. The brucellosis prevalence was 4.17 times greater in mainland animals than on Marajó Island, with the highest prevalence in Tailândia (11.30 %) and Paragominas (12.38 %). Brucellosis seroprevalence was significantly influenced (p?<?0.05) by reproductive status, with pregnant females being most vulnerable. These results demonstrate that brucellosis infection is active in the Brazilian region containing the largest buffalo population and that this disease poses a threat to public health and buffalo production in Pará.  相似文献   

Genetic diversity of Mycoplasma hyopneumoniae isolates of abattoir pigs     

Audrey Charlebois  Corinne Marois-Créhan  Pierre Hélie  Carl A. Gagnon  Marcelo Gottschalk  Marie Archambault 《Veterinary microbiology》2014,168(2-4):348-356

Mycoplasma hyopneumoniae, the causative agent of porcine enzootic pneumonia, is present in swine herds worldwide. However, there is little information on strains infecting herds in Canada. A total of 160 swine lungs with lesions suggestive of enzootic pneumonia originating from 48 different farms were recovered from two slaughterhouses and submitted for gross pathology. The pneumonic lesion scores ranged from 2% to 84%.Eighty nine percent of the lungs (143/160) were positive for M. hyopneumoniae by real-time PCR whereas 10% (16/160) and 8.8% (14/160) were positive by PCR for M. hyorhinis and M. flocculare, respectively. By culture, only 6% of the samples were positive for M. hyopneumoniae (10/160). Among the selected M. hyopneumoniae-positive lungs (n = 25), 9 lungs were co-infected with M. hyorhinis, 9 lungs with PCV2, 2 lungs with PRRSV, 12 lungs with S. suis and 10 lungs with P. multocida. MLVA and PCR-RFLP clustering of M. hyopneumoniae revealed that analyzed strains were distributed among three and five clusters respectively, regardless of severity of lesions, indicating that no cluster is associated with virulence. However, strains missing a specific MLVA locus showed significantly less severe lesions and lower numbers of bacteria. MLVA and PCR-RFLP analyses also showed a high diversity among field isolates of M. hyopneumoniae with a greater homogeneity within the same herd. Almost half of the field isolates presented less than 55% homology with selected vaccine and reference strains.  相似文献   

Long-term mild hypoxia does not reduce thermal tolerance or performance of the freshwater prawn Macrobrachium tenellum     

Nelly Tremblay  Marcelo García-Guerrero  Fernando Díaz  Claudia Caamal-Monsreal  Gabriela Rodríguez-Fuentes  Kurt Paschke  Paulina Gebauer  Carlos Rosas 《Aquaculture Research》2022,53(1):63-74

The present study was designed to assess the performance of the freshwater prawn Macrobrachium tenellum in optimal and sub-optimal dissolved oxygen conditions, considering increasing environmental pressures. Thermal tolerance and thermal metabolic scope (TMS) with related integrated biomarker response (IBR) were measured in prawns exposed to normoxia (80% air saturation), mild (40% air saturation) and severe hypoxia (25% air saturation) at three exposure time points (10, 20 and 30 days). Effects of hypoxia on thermal tolerance were not detectable over time; they were perhaps masked by hyperventilation, or by an increase or diversion of haemolymph processes. After 30 days, TMS was 11% higher in mild hypoxia compared with normoxia, while it was 64% lower in severe hypoxia, indicating the loss of aerobic metabolism capacity during the latter. Mild-hypoxia prawns maintained a high IBR over time, supported by antioxidant enzyme activities (mainly superoxide dismutase), which helped avoid the serious oxidative damage (proteins and lipids) seen in severe hypoxia animals, as well as lower acetylcholinesterase activity that indicated failure of communication between the nervous and locomotor systems. Our results documented a high tolerance by M. tenellum to mild-hypoxia events, which should be further tested under seasonal and extreme habitat/tank temperatures.  相似文献   

Assessment of different ionic adjustment strategies in low-salinity water on the growth of Litopenaeus vannamei and microbial community stoichiometry in a synbiotic nursery system     

Otvio Augusto Lacerda Ferreira Pimentel  Valdemir Queiroz de Oliveira  Caio Rubens do Rêgo Oliveira  William Severi  Alfredo Olivera Glvez  Andr Megali Amado  Luis Otavio Brito 《Aquaculture Research》2022,53(1):50-62

The aim of this study was to evaluate different ionic adjustment strategies in oligohaline water on the growth of Litopenaeus vannamei and C:N:P stoichiometric ratios of the floc microbial community (MC) in synbiotic nursery system. A 35-day culture (2000 PL's/m³) was carried out in 60 L units in a completely randomized experimental design, with three treatments: T1—seawater diluted to a salinity of 2.5 g/L (control), T2—water with a salinity of 2.5 g/L with potassium (K?) adjusted and T3—water at a salinity of 2.5 g/L with its Ca:Mg:K ratio adjusted to 1:3:1, each treatment in triplicates. The MC of flocs and the dissolved fraction (DF) was separated by filtration, where MC >1.6 µm and DF <1.6 µm. The juveniles reached a final weight of 0.40 ± 0.09–0.49 ± 0.04 g, survival above 80% and an average yield of 0.69 ± 0.18–0.81 ± 0.02 kg/m³, without significant differences among the treatments. A stabilizing trend of C:P, C:N and N:P ratios of MC was observed considering the variations of C:N:P in the DF, indicating a homeostatic behaviour of the floc MC, as occurs in systems with high nutrient availability. Our results indicate that the major ions initial concentrations (Ca²⁺: 25.07 mg/L, Mg²⁺: 89.75 mg/L and K?: 25.00 mg/L), total alkalinity 100.00 mg/L and total hardness 433.30 mg/L provide conditions that do not limit shrimp growth in oligohaline water synbiotic nursery system.  相似文献   

Distribution of glyphosate-resistant and glyphosate-susceptible hairy fleabane (Conyza bonariensis) in central California and their phenological development     

Anil Shrestha  Katrina M. Steinhauer  Marcelo L. Moretti  Bradley D. Hanson  Marie Jasieniuk  Kurt J. Hembree  Steven D. Wright 《Journal of pest science》2014,87(1):201-209

Glyphosate-resistant (GR) hairy fleabane was first documented in California in 2007. A preliminary study comparing plants from this population to a glyphosate-susceptible (GS) population determined that they developed more rapidly than the GS plants. However, it was not known if this was a general characteristic of all GR populations. Therefore, seeds of hairy fleabane were collected from 122 locations in central California. Plants from each location were grown and tested for resistance using a shikimate enzyme assay. Seeds from 90 locations germinated of which 27 % were determined as GR, 21 % as GS, and 52 % as intermediate/mixed. Plants from five GR and five GS populations, as determined by the assay, were randomly selected for comparisons and were grown in 2010/2011. Time taken by each plant to reach key phenological stages was recorded and converted into growing degree day (GDD) using a base temperature of 4.2 °C. The biomass of each plant was recorded at seed set. The five GR and GS plants had similar phenological development rates and biomass. Therefore, the differences previously identified between the two populations were not present in the additionally tested populations. The phenological development was hence described by a common GDD model with the plants requiring 374, 711, 970, 1289, and 1551 GDD, to reach the rosette, bolting, first bud, first flower, and first seed stages, respectively. This study shows widespread distribution of GR hairy fleabane in central California, provides useful information on biology of this weed for management, and suggests possible label changes to herbicide manufacturers.  相似文献   

Genetic parameters relating isoflavone and protein content in soybean seeds   总被引：3，自引：0，他引：3  

Lucimara Chiari  Newton Deniz Piovesan  Lucas Koshy Naoe  Inês Chamel José  José Marcelo Soriano Viana  Maurilio Alves Moreira  Everaldo Gonçalves de Barros 《Euphytica》2004,138(1):55-60

Isoflavones are a class of compounds present in high amounts in soybean seeds, which can be used for prevention and treatment of several chronic diseases. Proteins present in soybean seeds are the basis for the high nutritional value and versatility of this leguminous species in animal and human feeding. The main goals of this work were to estimate heritabilities for isoflavone contents in soybean seeds and the correlation between isoflavone and protein contents. Commercial variety IAC-100 (high isoflavone and normal protein contents) and the line BARC-8 (low isoflavone and high protein contents) were crossed, and one single F₁ plant derived 97 F₂ seeds, which were used to obtain F₃ seeds. A sample of F₃ seeds from each F₂ plant was used for isoflavone determination by HPLC and protein by the Kjeldahl method. Six isoflavone forms were detected: daidzin, genistin, glycitin, malonyldaidzin, malonylgenistin and malonylglycitin. Total isoflavone contents ranged from 427.92 to 965.89 μg per gram of dry seed and the protein content ranged from 45.17 to 34.95% in BARC-8 and IAC-100, respectively. Our results indicate that it is possible to select for high isoflavone content in early breeding generations because the broad sense heritabilities for the contents of the various isoflavone forms were higher than 90%. In addition, high correlation values among the contents of the individual isoflavone forms were observed (between 0.80 and 0.98). However, negative correlation values were obtained between isoflavone and protein contents, ranging from −0.51 to −0.37 for the different isoflavone forms. The correlation value of −0.47 between total isoflavone and protein contents confirmed the negative correlation between these two parameters, as reported by other authors. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献