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1.
Transl Anim Sci ; 8: txae045, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585172

RESUMO

One hundred and eighty crossbred beef steers (406.0 ±â€…2.2 kg) were used to determine the impact of a novel direct-fed microbial (DFM) on growth performance, carcass characteristics, rumen fermentation characteristics, and immune response in finishing beef cattle. Steers were blocked by body weight (BW) and randomly assigned, within block, to 1 of 2 treatments (3 replicates/treatment: 30 steers/replicate). Treatments included: (1) no DFM (control) and (2) DFM supplementation at 50 mg ∙ animal-1 ∙ d-1 (BOVAMINE DEFEND Plus). All steers were fed a high-concentrate finishing diet and individual feed intake was recorded daily via the GrowSafe system. BWs were collected every 28 d. On day 55, 10 steers per pen were injected with ovalbumin (OVA). Jugular blood samples were collected from each steer on days 0, 7, 14, and 21 post injection. On day 112, the same steers were injected again with OVA and intramuscularly with a pig red blood cell solution. Jugular blood samples were collected from each steer on days 0, 7, 14, and 21 post injection. On day 124, rumen fluid was collected from 3 steers per treatment and used to estimate in vitro rumen fermentation characteristics. Equal numbers of steers per treatment were transported to a commercial abattoir on days 145, 167, and 185 of the experiment, harvested, and carcass data were collected. Initial BW was similar across treatments. On days 28 and 55, steers receiving DFM had heavier BW (P < 0.01) compared to controls. The average daily gain was greater in DFM-supplemented steers from days 0 to 28 (P < 0.01) and days 0 to 55 (P < 0.01) of the experiment compared to controls. Overall dry matter intake (DMI) was greater (P < 0.04) and overall feed efficiency was similar in DFM-supplemented steers compared to controls. Dressing percentage (P < 0.02) was greater in steers receiving DFM compared to controls. Antibody titers to injected antigens were similar across treatments. However, red blood cell superoxide dismutase activity was greater (P < 0.05) in DFM-supplemented steers compared to controls. In vitro molar proportions of isobutyric and butyric acid were greater (P < 0.01) and dry matter (DM) digestibility tended (P < 0.07) to be greater in rumen fluid obtained from steers supplemented with DFM. These data suggest that BOVAMINE DEFEND Plus supplementation improves growth performance during the initial period of the finishing phase, increases overall DMI and dressing percentage, and may impact antioxidant status in beef cattle.

2.
Trop Anim Health Prod ; 56(3): 120, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607525

RESUMO

The current study evaluated the effects of supplementing cassava root silage (CRS) to dairy cows grazing on Megathyrsus maximus cv Mombasa on nutrient intake and digestibility, as well as on milk production and composition. Ten primiparous Girolando cows with average body weight ± (SEM) of 373.45 ± (63.55) kg were used in a replicated 5 × 5 Latin square. Animals were subjected to five treatments: (I) grazing cows without supplementation (WCS); (II) grazing cows provided with 5 kg DM of supplement without CRS (0 g/kg DM of CRS) or including (III) 260, (IV) 520, and (V) 780 g/kg DM of CRS. Statistical analyses were performed using the PROC MIXED of SAS with significance at P < 0.05. Intake of neutral detergent fiber (NDF) and ether extract decreased (P < 0.01), while intake of non-fiber carbohydrates increased (P < 0.01), with increased CRS in the diets. Total DM intake and digestibility of DM, and digestibility of nutritional components were lower (P < 0.03) in WCS animals compared to supplemented animals, except for intake and digestibility of NDF, which was the opposite. Milk yield (MY) and fat corrected milk (FCM), as well as all milk components were unaffected (P > 0.05) by CRS inclusion. In contrast, MY, FCM, protein, lactose, casein, and non-fat milk solids (NFMS) were greater for animals that received supplementation (P < 0.05), compared to animals WCS. Milk fat and total dry extract (TMS) did not differ (P > 0.11) between two groups. In conclusion, CRS may be a potential corn meal replacer in the supplement of dairy cows under tropical conditions.


Assuntos
Manihot , Feminino , Bovinos , Animais , Leite , Silagem , Quênia , Nutrientes , Extratos Vegetais
3.
Trop Anim Health Prod ; 55(2): 110, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36917341

RESUMO

A meta-analysis was conducted to evaluate the effects of dietary palm kernel cake inclusion (PKCInclusion) on the nutrient intake and digestibility, as well as on the performance of cattle under grazing and confined systems. Additionally, potential maximum safe levels (MSL) for PKCInclusion were explored for cattle under those systems using a broken-line approach. Overall, 22 studies for 85 treatment means and 747 experimental units were included in the dataset used for the meta-analysis in which, quantitative responses to increasing PKCInclusion levels were fitted using a mixed model, considering the study as a random effect. Additionally, all studies tested a treatment without the inclusion of PKC (PKCInclusion = 0 g/kg DM) in the concentrate and total mixed ration fed to grazing and confined animals, respectively. In grazing animals, intake, and digestibility of dry matter (DM), as well as intake of total digestible nutrient (TDN) and digestibility of crude protein (CP) decreased linearly (P < 0.01) as PKCInclusion increased. Conversely, the intake and digestibility of neutral detergent fiber (NDF) increased linearly (P < 0.01). Additionally, the intake of CP showed a quadratic decreasing pattern (P < 0.01) with the increase in dietary PKCInclusion. In confined animals, intake of DM, CP, NDF, and TDN revealed quadratic patterns (P < 0.01) as PKCInclusion increased. The digestibility of DM, CP, NDF, as well as TDN concentration showed a linear decreasing pattern (P < 0.05) as PKCInclusion increased. For performance, data revealed that average daily gain (ADG) decreased linearly (P < 0.01) in grazing and confined animals with the increase in PKCInclusion. Feed efficiency (FE) decreased linearly (P < 0.01) in grazing animals, whereas it showed a linear increase (P < 0.05) in confined animals. Exploration of the quadratic relationships of intake of DM, CP, NDF, and TDN with PKCInclusion in confined animals revealed MSL values for PKC ranging from 85.56 ± 14.2 to 126.4 ± 14.7 g PKC/kg DM. In grazing animals, exploration of the quadratic relationship of intake of CP with PKCInclusion, revealed an MSL value of 96.23 ± 9.01 g PKC/kg DM. In conclusion, data revealed that the use of PKC in both confined and grazing systems reduces the nutrient utilization and performance of cattle in a dose-dependent manner without a maximum safe level that does not reduce animal performance.


Assuntos
Ração Animal , Digestão , Bovinos , Animais , Ração Animal/análise , Dieta/veterinária , Ingestão de Alimentos , Nutrientes , Fibras na Dieta
4.
An Acad Bras Cienc ; 94(suppl 3): e20211394, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36197363

RESUMO

The characteristics of milk are controlled by several genes, with emphasis on the four genes from casein, CSN1S1; CSN1S2; CSN2 and CSN3, which are responsible encoding of fractions the milk protein. The study of genetic variants in these genes, seek to investigate alleles, insertions or deletions, that can directly reflect on productive characteristics, indicating differences in milk quality, composition and yield. The CSN1S1 and CSN3 genes were analyzed in lactating Murrah buffaloes using nucleotide sequencing. An SNP was found in the amplified fragment of the CSN1S1 gene, located in nucleotide number 2,123 of the promoter region in position nt-258 (A/G). As for the CSN3 gene, two SNPs of exon number 4 were identified in codons 33 (ACC/ATC) and 34 (ACC/ACT) of the analyzed fragment. This study contributes to important associations between genetic variants and the desired characteristics of milk and its derivatives in future studies, because the variants found may be associated with the quality of milk, enabling genetic selection to be assisted by molecular markers, indicating a major advance that makes it possible to select animals early.


Assuntos
Búfalos , Caseínas , Animais , Brasil , Búfalos/genética , Caseínas/genética , Feminino , Lactação , Proteínas do Leite/genética , Nucleotídeos
5.
Trop Anim Health Prod ; 54(6): 362, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36287275

RESUMO

This study explored the effects of different supplementation strategies during the dry and rainy seasons in the tropics on the carcass traits and meat quality of Nellore cattle produced under grazing conditions. Additionally, a cost assessment of the supplementation strategies was conducted to define the most suitable ones from an economic standpoint. Twenty-eight non-castrated male animals (18 months) with an initial body weight of 327.9 ± 4.2 kg were used. The animals were equitably distributed in a randomized complete design thorough four supplementation strategies as follows: (i) mineral supplementation (MS) in both dry and rainy seasons (MS/MS), (ii) MS during the dry season and concentrate supplementation (CS) during the rainy season (MS/CS), (iii) CS during the dry season and MS during the rainy season (CS/MS), and (iv) CS in both dry and rainy seasons (CS/CS). Thereafter, carcass traits, primary carcass cut yields, meat quality traits, and chemical composition of the meat of cattle produced across different supplementation strategies were determined. Data revealed that animals under CS/CS showed the greatest (P < 0.01) hot carcass weights among the other supplementation strategies evaluated. Conversely, supplementation strategy did not affect (P > 0.10) the carcass traits (the ribeye area, final pH, and forequarter), meat quality traits (shear force, myofibrillar fragment index, sarcomere length, and color), and meat chemical composition (crude protein, fat, and moisture) of the animals. A cost assessment of the supplementation strategies revealed that CS/CS had the highest production costs. Nevertheless, CS/CS had the greatest income and profit, while MS/MS had the lowest ones. In conclusion, data suggest that cattle grazing on tropical forage under CS during at least one season (i.e., dry or rainy) produce similar meat quality traits and chemical composition of meat to those observed for animals under CS in both seasons. Additionally, the last supplementation strategy revealed the greatest profit indicators among the other explored.


Assuntos
Carne , Espectrometria de Massas em Tandem , Bovinos , Masculino , Animais , Espectrometria de Massas em Tandem/veterinária , Estações do Ano , Suplementos Nutricionais/análise , Minerais , Composição Corporal
6.
Animals (Basel) ; 12(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36009734

RESUMO

This meta-analysis aimed to identify knowledge gaps in the scientific literature on future fetal-programming studies and to investigate the factors that determine the performance of beef cows and their offspring. A dataset composed of 35 publications was used. The prenatal diet, body weight (BW), average daily gain (ADG) during pregnancy, and calf sex were elicited as possible modulators of the beef cows and their offspring performance. Then, the correlations between these variables and the outcomes of interest were investigated. A mixed multiple linear regression procedure was used to evaluate the relationships between the responses and all the possible explanatory variables. A knowledge gap was observed in studies focused on zebu animals, with respect to the offspring sex and the consequences of prenatal nutrition in early pregnancy. The absence of studies considering the possible effects promoted by the interactions between the different stressors' sources during pregnancy was also detected. A regression analysis showed that prenatal diets with higher levels of protein improved the ADG of pregnant beef cows and that heavier cows give birth to heavier calves. Variations in the BW at weaning were related to the BW at birth and calf sex. Therefore, this research reinforces the importance of monitoring the prenatal nutrition of beef cows.

7.
Ces med. vet. zootec ; 17(2): 36-62, mayo-ago. 2022. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1404091

RESUMO

Resumo Na flora amazônica, incontáveis plantas possuem compostos bioativos, que potencialmente podem ser utilizados como moduladores da fermentação ruminal. Apesar da importância, poucos estudos têm sido desenvolvidos para avaliar a utilização de plantas amazônicas como aditivos alimentares naturais na nutrição de ruminantes. Assim, objetiva-se apresentar um panorama dos dados científicos da literatura sobre os efeitos do uso dos extratos de açaí, copaíba, salva-do-marajó, pupunha e bacuri na fermentação ruminal e os seus potenciais de utilização na dieta de ruminantes. O açaí (Euterpe oleracea Mart.), possui 16,08 mg/g de matéria seca de flavonoides, compostos com potente ação antimicrobiana. Estudos com suplementação do óleo de açaí tem mostrado efeitos modulatórios na fermentação ruminal e na produção de leite de ovelhas e vacas. Adicionalmente, a oleoresina de copaíba (Copaifera spp.) e a manteiga das sementes de bacuri (Platonia insignis Mart.), possuem, respectivamente, 88% e 41% de terpenos; a composição fitoquímica do óleo de salva-do-marajó (Hyptis crenata Pohl ex Benth) ainda não está completamente caracterizada, mas esta fonte está majoritariamente composta por terpenos cânfora (33,62%), 1,8-cineol (19,76%) e α-pineno (15,24%), que apresentam atividade in vitro antimicrobiana, capaz de reduzir a produção total de gás em ambiente ruminal in vitro. A pupunha, fruto da pupunheira (Bactris gasipaes Kunth.), possui 355,95 mg/kg de carotenoides, com efeito antimicrobiano in vitro contra algumas cepas bacterianas. Os achados desta revisão demonstram as potencialidades dos extratos amazônicos na maximização da produção animal, em razão dos possíveis efeitos na modulação da fermentação ruminal, sendo encorajada a realização de estudos adicionais visando uma maior exploração deles. Embora, atualmente, não existam estudos associados aos efeitos do açaí, salva-do-marajó, pupunha e bacuri na fermentação ruminal, pressupõe-se que pela sua composição fitoquímica, poderiam ter um efeito semelhante aos ionóforos na produção de ruminantes.


Abstract In the Amazonian Forest, diverse plants have bioactive compounds, which can potentially be used as modulators of ruminal fermentation. Despite the importance, few studies have been developed to evaluate the use of extracts from Amazonian plants as natural feed additives in ruminant nutrition. Thus, the objective of this study is to present a brief overview of the scientific data in the literature regarding the effects of the use of extracts of açaí, copaíba, sage-do-marajó, peach palm, and bacuri on the ruminal fermentation and their potential for use in the diet of ruminants. Açaí (Euterpe oleracea Mart.) has 16.08 mg/g of dry matter of flavonoids, compounds with potent antimicrobial activity. Studies with açaí oil supplementation have shown modulatory effects on rumen fermentation and milk production in sheep and cows. Additionally, the copaiba oleoresin (Copaifera spp.) and the bacuri (Platonia insignis Mart.) seed butter have 88% and 41% of terpenes, respectively; the phytochemical composition of marajó sage oil (Hyptis crenata Pohl ex Benth) is not completely resolved, but this source is mostly composed of the terpenes, camphor (33.62%), 1,8-cineole (19.76%) and α-pinene (15.24%), which have in vitro antimicrobial effects against different bacterial strains. The findings of this review demonstrate the potential of Amazonian extracts in maximizing animal production, due to the possible effects on the modulation of ruminal fermentation, being encouraged to carry out additional studies aiming at a greater exploration of them. Although, there are no current studies associated with the effects of açaí, sage, peach palm, and bacuri on rumen fermentation, it is inferred that, due to their phytochemical composition, they may have a similar effect to ionophores on ruminant production.


Resumen En la selva amazónica, innumerables plantas poseen compuestos bioactivos, que potencialmente pueden ser utilizados como moduladores de la fermentación ruminal. A pesar de la importancia, han sido desarrollados pocos estudios evaluando el uso de extractos de plantas amazónicas como aditivos alimentarios naturales en la nutrición de rumiantes. Así, el objetivo de este estudio es presentar un breve panorama de los datos científicos en la literatura sobre los efectos del uso de extractos de açaí, copaíba, salvia-do-marajó, chontaduro y bacuri en la fermentación ruminal y su potencial de uso en la dieta de los rumiantes. Açaí (Euterpe oleracea Mart.) tiene 16,08 mg/g de materia seca de flavonoides, compuestos con potente acción antimicrobiana. Los estudios con suplementos de aceite de açaí han demostrado efectos moduladores sobre la fermentación ruminal y la producción de leche en ovejas y vacas. Adicionalmente, la oleorresina de copaiba (Copaifera spp.) y la mantequilla de semilla de bacuri (Platonia insignis Mart.) poseen 88% y 41% de terpenos, respectivamente; la composición fitoquímica del aceite de salvia de marajó (Hyptis crenata Pohl ex Benth) no está completamente resuelta, sin embargo esta fuente está mayoritariamente compuesta de los terpenos alcanfor (33,62%), 1,8-cineol (19,76%) y α-pineno (15,24%), los cuales poseen efecto antimicrobiano in vitro frente a diferentes cepas bacterianas. Los hallazgos de esta revisión demuestran el potencial de los extractos amazónicos en la maximización de la producción animal, debido a sus posibles efectos sobre la modulación de la fermentación ruminal, siendo incentivados a realizar estudios adicionales con el objetivo de una mayor exploración de estos. Aunque actualmente no existen estudios asociados a los efectos del açaí, la salvia, el chontaduro y el bacuri en la fermentación ruminal, se supone que, por su composición fitoquímica, podrían tener un efecto similar a los ionóforos en la producción de rumiantes.

8.
Trop Anim Health Prod ; 54(4): 206, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35676389

RESUMO

This study was conducted to evaluate the effects of two methods of provision of açai seed (AS) as a fiber source (coarsely broken or whole) for feedlot beef cattle on the intake, digestibility, and ruminal parameters. Four bulls (male, non-castrated, and rumen fistulated), with an average body weight of 340 ± 31 kg, distributed in two simultaneous 2 × 2 Latin squares, were used. The treatments were two methods of processing of the açai seed, as follows: whole açai seed (WAS), and coarsely broken açai seed (CBAS). The dry matter (DM), crude protein (CP), and neutral detergent fiber (NDF) intake were higher (P < 0.10) with the use of CBAS. The digestibility of DM and nutrients was not affected (P > 0.10) by AS processing. Acetate and total volatile fatty acids concentrations, and acetate:propionate ratio were higher with the CBAS diet, whereas the pH was higher with the WAS diet. The concentrations of propionate, butyrate, and ruminal ammonia nitrogen (NH3) did not change with AS processing. Thus, coarsely broken açai seed increases the intake of DM and nutrients without altering the digestibility. Furthermore, it increases the concentrations of total fatty acids and acetate.


Assuntos
Fibras na Dieta , Rúmen , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão , Fermentação , Masculino , Propionatos/metabolismo , Rúmen/metabolismo , Sementes/química
9.
Biosci. j. (Online) ; 38: e38079, Jan.-Dec. 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1397162

RESUMO

The effects of higher supplementation levels for young Nellore heifers fed tropical forages including their influence on puberty, need to be understood. This study investigated the influence of high and moderate supplementation levels on puberty onset and the productive performance of Nellore heifers. Thirty-six Nellore heifers (225 + 3.52 kg) were used in a completely randomized design, with three treatments: (I) no concentrate (control); (II) concentrate supplement at 4 g/kg body weight (BW); (III) concentrate supplement at 8 g/kg BW. Increased supplement level led to a linear increase in average daily gain (P < 0.05). The high supplementation level (8 g/kg BW) had the highest proportion of corpus luteum presence (82% of heifers), compared to the 4 g/kg BW treatment group (67%) and the control group (33%; P < 0.05). Our findings indicate that providing a high level of energy supplementation to Nellore heifers for approximately 100 d improves performance and increases the proportion of heifers that reach puberty.


Assuntos
Bovinos , Pastagens , Suplementos Nutricionais
10.
Trop Anim Health Prod ; 53(4): 433, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34386894

RESUMO

This study evaluated the effects of dietary inclusion of cracked babassu coconut (CBC) in the supplement on nutrient utilization, performance, and milk fatty acid (FA) composition of dairy cows grazing Megathyrsus maximus cv. Mombasa. Five multiparous Holstein × Zebu mid-lactation cows (125 ± 16.5 days in milk) were assigned to five dietary treatments (replacement of 0%, 20%, 40%, 60%, and 80% of ground corn with CBC, on a dry matter (DM) basis) in a 5 × 5 Latin square design. The intake of DM from the supplement, crude protein (CP), non-fiber carbohydrate (NFC), fat (ether extract (EE)), and total digestible nutrients (TDNs) decreased linearly (P < 0.05), while the intake of DM from forage increased linearly (P < 0.05), with the increase in CBC inclusion in the supplement. Conversely, total DM intake was unaffected (P > 0.05). The DM, NFC, EE, and TDN digestibility decreased linearly (P < 0.05), while organic matter (OM) digestibility decreased in a quadratic fashion (P < 0.05), as CBC inclusion in the supplement increased. Nevertheless, digestibility of CP was unaffected (P > 0.05). Milk yield and composition (lactose, fat, protein, casein, and majority of FA) showed a linearly decreasing pattern (P < 0.05) with the increasing of CBC inclusion. However, proportions of trans-vaccenic acid, rumenic acid, total monounsaturated FA, and odd- and branched-chain FAs increased linearly (P < 0.05). On the opposite, total saturated FA (SFA) and the n-6:n-3 FA ratio in milk fat decreased linearly (P < 0.01). Hence, replacement of corn meal with CBC up to 80% in the supplement decreases nutrient intake and digestibility, as well as milk yield response in grazing dairy cows. However, CBC inclusion may enhance the nutritional properties of milk fat.


Assuntos
Ácidos Graxos , Leite , Ração Animal/análise , Animais , Bovinos , Cocos , Dieta/veterinária , Suplementos Nutricionais , Digestão , Feminino , Quênia , Lactação , Nutrientes
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