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1.
Higher feeding diets effects on age and liveweight gain at puberty in crossbred Nelore × Hereford heifers 总被引:1,自引:1,他引:0
Júlio Otávio Jardim Barcellos Gabriel Ribas Pereira Eduardo Antunes Dias Concepta McManus Leonardo Canellas Mari Lourdes Bernardi Adriana Tarouco Ênio Rosa Prates 《Tropical animal health and production》2014,46(6):953-960
This study was conducted to determine the age and liveweight at puberty of 120 crossbred beef heifers submitted to four diets to achieve predetermined weight gains (kg/day): 0.5 (G500; n?=?32), 0.75 (G750; n?=?32), 1.0 (G1000; n?=?29), and 1.25 (G1250; n?=?27). Animals were classified depending on their level of crossing between Nelore (N) and Hereford (H): 25%N-75%H, 37.5%N-63.5%H, 43.7%N-56.7%H, 50%N-50%H, and 75%N-25%H. Reproductive evaluation was performed at the beginning and at the end of the experimental period by ultrasonography and hormone analysis. The average age and liveweight at puberty were 388.0?±?1.9 days and 331.4?±?1.3 kg, respectively. Animals from the 25%N-75%H group reached puberty earlier than heifers from other genetic groups supplemented with G1250 diet (P?<?0.05). Heifers with higher degree of Nelore (75%N-25%H) fed with G1000 diet showed estrus 42 days prior to mating, but only 57 % reached puberty at mating (P?<?0.05). Heifers with follicles of higher diameter reached puberty (P?<?0.05) earlier. Higher average daily weight gain showed a positive effect on follicular diameter and IGF-I level at puberty (P?<?0.01). Concentrations of GH were lower in heifers fed G1250 compared to G1000 diet (P?<?0.05). There was a significant interaction between nutritional level and insulin levels at puberty (P?<?0.01). We demonstrated the relationship between IGF-I and average daily gain on the onset of puberty in heifers. In conclusion, heifers submitted to the higher feeding level showed a higher follicular diameter and were younger at puberty. 相似文献
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Pecinali NR Gomes RN Amendoeira FC Bastos AC Martins MJ Pegado CS Bastos OM Bozza PT Castro-Faria-Neto HC 《Veterinary parasitology》2005,134(1-2):121-130
Toxocara canis is a nematode of the Ascaridae family that normally parasites the small intestine of canid species. Humans are accidentally infected upon ingestion of embryonated eggs, and can manifest several clinical alterations such as fever, hepatomegaly, splenomegaly, respiratory symptoms, muscle pain and anorexia. In the present work, we investigated the kinetics of tissue distribution of L2 larva in lungs, liver, kidney, brain, skeletal muscle and myocardium. Also, we analyzed the blood and bronchoalveolar lavage fluid (BAL) for levels of IL-6, IFN-gamma, eotaxin and Regulated on Activation Normal T Cell Expressed and Secreted (RANTES) in experimental murine T. canis infection. We observed liver, lung and kidney lesions correlated to larva migration as early as the first day of infection. After the seventh post-infection day, larva could also be detected in brain, skeletal muscle and heart, as an indicator of biphasic migration pattern. Increased inflammatory activity was detected in BAL and plasma of infected animals, as was an intense eosinophil migration associated with an increase in the levels of all the cytokines studied. In conclusion, our results establish a tight correlation between tissue lesions caused by larva migration and increased plasma levels of pro-inflammatory and eosinophil chemotactic cytokines. Thus, murine T. canis infection may prove to be useful in understanding the role of cytokines in infection. 相似文献
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Gil de los Santos JR Storch OB Fernandes CG Gil-Turnes C 《Veterinary microbiology》2012,156(3-4):448-451
The probiotic properties of Pichia pastoris and of a recombinant P. pastoris containing the Clostridium perfringens alpha toxin gene were evaluated in broilers. One-day-old chicks randomly divided in four groups were fed with commercial feed devoid of antibacterials. The control group (1) received plain food, while the other groups were supplemented with either P. pastoris (2), the recombinant P. pastoris (3) or Bacillus cereus var. Toyoi (4). At day 49, live weights, feed efficiency and seroconversions were higher (P<0.05) in the supplemented groups than in the control groups. Group 3 showed the best results, while group 2 had lower weight gain than groups 3 and 4 although food conversion was better than in group 4. Seroconversions were not different (P>0.05) among the supplemented groups. Adverse reactions were not observed in histopathologic evaluation. We concluded that P. pastoris and the recombinant P. pastoris could be used as probiotics in broilers. 相似文献
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Ciro Abbud Righi Otávio Camargo Campoe Marcos Silveira Bernardes Aureny Maria Pereira Lunz Sônia Maria Stefano Piedade Carlos Rodrigues Pereira 《Agroforestry Systems》2013,87(6):1351-1362
The coffee leaf-miner (CLM) (Leucoptera coffeella Guérin-Mèneville; Lepidoptera: Lyonetiidae), the main pest of coffee plants, occurs widely throughout the Neotropics where it has a significant, negative economic and quantitative impact on coffee production. This study was conducted in a rubber tree/coffee plant interface that was influenced by the trees to a varying degrees depending on the location of the coffee plants, i.e. from beneath the rubber trees, extending through a range of distances from the edge of the tree plantation to end in a coffee monocrop field. The most severe damage inflicted on coffee plants by the CLM (number of mined leaves) from April, which marks the start of the water deficit period, until September 2003 was in the zone close to the rubber trees, whereas the damage inflicted on plants in the monocropped field was comparable to that on coffee plants grown directly beneath the rubber trees, which received about 25–40 % of the available irradiance (Ir—available irradiation at a certain position divided by the irradiation received in full sunlight, i.e. in the monocrop). From May until July damage caused by the CLM nearly doubled in each month. In midwinter (July), the damage decreased perceptibly from the tree edge toward the open field. From September onward, with the rising air temperatures CLM damage in the coffee monocrop started to increase. Based on these results, we conclude that coffee plants grown in the full sun incurred the most damage only at the end of winter, with warming air temperatures. Coffee plants grown in shadier locations (25–40 % Ir) were less damaged by the CLM, although a higher proportion of their leaves were mined. The rubber trees probably acted as a shelter during the cold autumn and winter seasons, leading to greater CLM damage over a distance outside the rubber tree plantation that was about equal to the height of the trees. Future studies should attempt to relate leaf hydric potential to pest attack in field conditions. More rigorous measurements of shade conditions could improve our understanding of the relationship of this factor to CLM attack. 相似文献
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Rodrigo Otávio
De Almeida Ozório Carlos Andrade Viriato Manuel Freitas Andrade Timóteo Luís Eugénio Castanheira da Conceição Luisa Maria Pinheiro Valente 《Journal of the World Aquaculture Society》2009,40(1):95-103
Although reported as a slow growing species, to date information regarding nutritional dynamics of blackspot seabream, Pagellus bogaraveo, is limited, especially during ongrowing phase. This study determined the effects of different feeding levels on growth response, body composition, and energy expenditure of blackspot seabream juveniles (initial weight = 64 g). Fish were allocated in nine indoor tanks (15 fish per tank) and fed a basal diet twice daily at increasing levels (2.5, 3.3, and 4.1 g feed/kg0.8/d) for 138 d. Growth response decreased with decreasing feeding levels, but only at 2.5 g feed/kg0.8/d (P < 0.001). Differences in growth rates were positively correlated with body lipid content (r2 = 0.90). Net protein utilization decreased with each increase in feeding level. The energy requirement for zero growth (maintenance) and the estimated energy loss on starvation were calculated as 22.6 and 17.9 kJ/kg0.8/d, respectively. The energy cost for protein and lipid gain was calculated as 3.8 and 1.4 kJ/kJ energy deposited, respectively. This study suggested that blackspot seabream may grow slower than the other close‐related species because of its higher demand of dietary protein energy in favor of lipid deposition. 相似文献
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Everton Dezordi Sartori Leonardo Canali Canellas Gabriel Ribas Pereira Fernanda Gomes Moojen Helena Robatini Carvalho Júlio Otávio Jardim Barcellos 《Tropical animal health and production》2017,49(2):273-279
This study was conducted on 78 13-month-old crossbred beef heifers that weighed 215 kg in Southern Rio Grande do Sul (RS) State, Brazil. We evaluated the performance of beef heifers that were reared in a pasture system that received a mineral supplement energy-type protein with added sodium lasalocid (LAS). The heifers were randomly and uniformly divided into 2 groups, with 39 animals in each group. One group of animals received a mineral supplement energy-type protein without sodium lasalocid (CON), and the other group received a mineral supplement energy-type protein with added LAS. The mean feed intake, the body weight (BW), the average daily gain (ADG), the body condition score (BCS), and ovarian cyclicity were recorded, and economic parameters were calculated. No differences in supplement intake were observed between the groups, which ensures adequate intake of the other components of the mineral mixture, which are part of the nutritional requirements for the production process. Similarly, no difference in the ADG was observed between treatments. We observed that the heifers in the LAS group had a higher BW gain (51 kg) that the CON heifers (40 kg; P?<?0.05). In addition, LAS-supplemented heifers had a higher BCS (3.53) than CON heifers (3.38) at the end of the experiment (P?<?0.05). The heifers supplemented with LAS had a higher profitability than the CON heifers, even with the higher cost of the supplement containing LAS; this effect was due to the higher live BW at the end of the study. We concluded that the administration of a mineral supplement energy-type protein with added LAS has beneficial effects on beef heifers in terms of production and economic feasibility. 相似文献
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Ananias Francisco Dias Júnior Ana Lúcia Martins Sodero Pincelli Ana Paula Camara da Silva álison Moreira da Silva Natália Dias de Souza Mario Tommasiello Filho José Otávio Brito 《林业研究》2021,42(6):2313-2321
As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are nee... 相似文献
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Pedro Vital Brasil Ramos Fabyano Fonseca e Silva Luiz Otávio Campos da Silva Gustavo Garcia Santiago Gilberto Romeiro de Oliveira Menezes José Marcelo Soriano Viana Roberto A. A. Torres Júnior Andrea Gondo Luiz F. Brito 《Reproduction in domestic animals》2020,55(3):266-273
Cow stayability plays a major role on the overall profitability of the beef cattle industry, as it is directly related to reproductive efficiency and cow's longevity. Stayability (STAY63) is usually defined as the ability of the cow to calve at least three times until 76 months of age. This is a late-measured and lowly heritable trait, which consequently constrains genetic progress per time unit. Thus, the use of genomic information associated with novel stayability traits measured earlier in life will likely result in higher prediction accuracy and faster genetic progress for cow longevity. In this study, we aimed to compare pedigree-based and single-step GBLUP (ssGBLUP) methods as well as to estimate genetic correlations between the proposed stayability traits: STAY42, STAY53 and STAY64, which are measured at 52, 64 and 76 months of cow's age, considering at least 2, 3 and 4 calving, respectively. ssGBLUP yielded the highest prediction accuracy for all traits. The heritability estimates for STAY42, STAY53, STAY63 and STAY64 were 0.090, 0.151, 0.152 and 0.143, respectively. The genetic correlations between traits ranged from 0.899 (STAY42 and STAY53) to 0.985 (STAY53 and STAY63). The high genetic correlation between STAY42 and STAY53 suggests that besides being related to cow longevity, STAY53 is also associated with the early-stage reproductive efficiency. Thus, STAY53 is recommended as a suitable selection criterion for reproductive efficiency due to its higher heritability, favourable genetic correlation with other traits, and measured earlier in life, compared with the conventional stayability trait, that is STAY63. 相似文献