RESUMO

This study was carried out to evaluate the use of tannin extract from Acacia mearnsii as a strategy to reduce methane (CH4 ) in two distinct cattle genotypes and its effect on intake, digestibility, microbial efficiency and ruminal fermentation. Four Nellore (Bos indicus) and four Holstein (Bos taurus) dry cows fitted with rumen cannula were assigned to two 4 × 4 Latin square design, in a 2 × 4 factorial arrangement, where each genotype represented a square receiving four tannin levels (commercial extract of A. mearnsii) in the diet (0%, 0.5%, 1.0% and 1.5% of dry matter). Tannin levels used did not cause a reduction in feed intake or rumen passage rate for both genotypes (p > 0.05), although there was a linear reduction in the degradation rate and ruminal disappearance of diet (p < 0.05). The increase in tannin levels reduced the amount of entodiniomorph protozoa in the Nellore cattle (p < 0.05). There was no change in N retention or microbial efficiency (p > 0.05), despite the linear reduction of nutrient digestibility and the synthesis of microbial nitrogen (p < 0.05). The ruminal CH4 production was reduced (p < 0.05) without reducing the short-chain fatty acid production. The threshold of 0.72% of tannin in the diet was estimated as the starting point for the reduction of ruminal CH4 production with long-term efficacy. Therefore, the use of low levels of tannin extract from A. mearnsii is a potential option to manipulate rumen fermentation in Nellore and Holstein cattle and needs to be further investigated.

Assuntos

RESUMO

This study aimed to determine the effect of using different sources of nitrogen to supply part of degradable intake protein needs in lactating goat performance and its effect on excretion of microbial purine derivatives and blood metabolites. Thirty-two lactating Saanen goats (body weight 38.85 ± 2.14 kg and 1979 ± 0.25 gday-1milk yield) were used in a one-way ANOVA completely randomized design. Goats were assigned to the following treatments for a 10-wk experimental period: 1) Control (canola meal as a nitrogen source); 2) Urea (0.5% urea); 3) Optigen (0.55% Optigen-Alltech.Inc., Lexington, KY) and 4) Polymer-Coated Urea (PCU-international patent number: A01K5/00, 0.7% PCU) based on dry mater intake. Non-protein nitrogen groups had a comparative effect (p > 0.05) between control and other treatments on milk composition, microbial protein synthesis and they affected on blood factors including urea, cholesterol, and ALT. Dry matter intake decreased (p > 0.05) in PCU, Optigen, Urea than Control goats. Synthesis of microbial protein in PCUgoats was 22.5 g day-1and it was greater (p > 0.05) than other treatments. Plasma cholesterol was increased in PCUand Optigen, whereas urea concentration was increased in Urea and Control goats. Milk production was higher in PCUthan Urea and Control. Feed conversion ratio was improved (p > 0.05) in PCU and Optigengoats versusother treatments.This study demonstrated that polymer-coated ureacan be utilized as a nitrogen source and improve goats milk performance.(AU)

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RESUMO

The objective was to evaluate the influence of diets on lambs using different levels of peach palm meal as a replacement for maize (0, 10, 40, 60, and 85% of diet dry matter) on the endogenous creatinine clearance (CC), urine concentration ratio of purine derivatives to creatinine (PDC index), and daily creatinine excretion (DCE) as a marker to estimate purine derivatives (PD) excretion from urinary spot samples collected at different time points (4, 8, 12, 16, 20, 24 h after morning feeding) compared to 24-h total urine collection. The measured parameters were voluntary intake, urinary volume, CC, DCE, the concentration of plasma creatinine, and PD and purine derivatives' excretion (PDE). Five lambs were allocated to metabolic cages and distributed in a 5 × 5 Latin square. Urine collection was taken daily on days 16 to 19 of each experimental period. The inclusion of peach palm meal linearly reduced the intake of dry matter (g kg BW−0.75, p = 0.005), crude protein (g kg BW−0.75, p = 0.010), metabolizable energy (MJ kg BW−0.75, p = 0.010) and CC (p < 0.0001). It also quadratically affected the urinary volume (p = 0.008) and DCE (p = 0.004). There was a linear decrease for PDC index (p = 0.032) and PDE (p < 0.0001) measured in the 24-h total urine with peach palm meal levels. The different times of spot urine sampling did not affect (p > 0.05) the PDC index and PDE. Peach palm meal decreases the CC thereby compromising the use of a mean value of DCE as a PDE marker in spot urine samples. There is greater accuracy when using different values of DCE obtained for each diet as markers for the PDE in spot urine samples. Unconventional foodstuffs of low palatability affecting the voluntary intake of feed change the renal function.

RESUMO

The objectives of this study were to evaluate the effect of crude protein (CP) levels in the diet of growing female buffaloes on nitrogen metabolism and estimate protein requirements for maintenance. Four female buffaloes were used, cannulated in the rumen, with an average initial body weight (BW) of 355 ± 3.5 kg, in a Latin square (4 × 4) with four animals and four levels of CP in the diet (70, 90, 110, and 130 g/kg dry matter (DM)) composed of corn silage and concentrate. The increase in protein intake with increasing levels of dietary CP resulted in a higher concentration of ammonia in the rumen and higher ruminal disappearance of PB. However, omasal flow of protein increased linearly as did the efficiency of microbial protein synthesis. The CP levels affected DM intake and other nutrients positively, but there was no effect on nutrient total digestibility. Nitrogen (N) balance, when expressed relative to N intake, had an average value of 48.5 % observed across. The protein requirement for the maintenance of growing female buffaloes was 4.6 g CP/kg BW(0.75).

Assuntos

RESUMO

The aim of the present study was to determine whether sunflower meal (SFM), a highly rumen degradable protein (RDP) source, can be substituted with non-protein nitrogen (NPN, urea) without impacting negatively on intake, digestibility, rumen fermentation and microbial nitrogen (N) synthesis (MNS) in wethers consuming low quality Eragrostis curvula hay. Five wethers were fed ad libitum, low quality hay and supplemented twice-daily in equal proportions, via the rumen cannulae, one of five iso-nitrogenous and iso-energetic supplements in a 5 × 5 Latin square design experiment. The supplements differed in the ratios of rumen degradable N (RDN) supplied by either SFM and/or urea and is presented as percentage of RDN supplied by urea: T0 (100 % SFM, 0 % urea); T15 (85 % SFM, 15 % urea); T30 (70 % SFM, 30 % urea); T45 (55 % SFM, 45 % urea) and T60 (40 % SFM, 60 % urea). Forage intake and total tract dry matter (DM) digestibility did not differ; however, higher forage neutral detergent fiber (NDF) digestibilities were observed in the sheep supplemented with the higher urea-treatments (T45 and T60) compared to T15. Neither rumen pH nor total rumen volatile fatty acid (VFA) concentraions differed. The mean rumen ammonia nitrogen (RAN) concentration of the sheep supplemented with T60 was higher than T30 (9.35 mg dL1 vs. 7.41 mg dL1); however, no differences were observed in MNS or efficiency of MNS among treatments. Results suggest that up to 60 % of RDN supplied by SFM can be substituted with urea, without affecting intake, digestibility or MNS in wethers fed a low quality tropical hay.(AU)

Assuntos

RESUMO

The aim of the present study was to determine whether sunflower meal (SFM), a highly rumen degradable protein (RDP) source, can be substituted with non-protein nitrogen (NPN, urea) without impacting negatively on intake, digestibility, rumen fermentation and microbial nitrogen (N) synthesis (MNS) in wethers consuming low quality Eragrostis curvula hay. Five wethers were fed ad libitum, low quality hay and supplemented twice-daily in equal proportions, via the rumen cannulae, one of five iso-nitrogenous and iso-energetic supplements in a 5 × 5 Latin square design experiment. The supplements differed in the ratios of rumen degradable N (RDN) supplied by either SFM and/or urea and is presented as percentage of RDN supplied by urea: T0 (100 % SFM, 0 % urea); T15 (85 % SFM, 15 % urea); T30 (70 % SFM, 30 % urea); T45 (55 % SFM, 45 % urea) and T60 (40 % SFM, 60 % urea). Forage intake and total tract dry matter (DM) digestibility did not differ; however, higher forage neutral detergent fiber (NDF) digestibilities were observed in the sheep supplemented with the higher urea-treatments (T45 and T60) compared to T15. Neither rumen pH nor total rumen volatile fatty acid (VFA) concentraions differed. The mean rumen ammonia nitrogen (RAN) concentration of the sheep supplemented with T60 was higher than T30 (9.35 mg dL1 vs. 7.41 mg dL1); however, no differences were observed in MNS or efficiency of MNS among treatments. Results suggest that up to 60 % of RDN supplied by SFM can be substituted with urea, without affecting intake, digestibility or MNS in wethers fed a low quality tropical hay.

Assuntos

RESUMO

This study evaluated the effect of using fresh sugar cane, sugar cane silage with or without Lactobacillus buchneri, and burnt sugar cane silage with or without L. buchneri on ingestive behavior, nitrogen balance and synthesis of microbial nitrogen compounds of dairy cows. Five ¾ Holstein x Gir crossbred cows, assigned to a 5 x 5 Latin square design, were given diets with a 60:40 forage: concentrate ratio on a dry matter basis, to meet an average body weight of 550 kg and production of 15 kg of milk per day. The treatment with fresh sugar cane showed higher values (p 0.05) for dry matter feed efficiency (3,133.3 vs 2,234.47 g DM h-1) and rumination (1,642.3 vs 1,222.93 g DM h-1) compared to the silages. There was a shorter total chewing time (58.7 vs 81.5 min. kg-1 DM) for fresh sugar cane when compared to silages without inoculum. The addition of microbial additive during ensiling of sugar cane did not alter (p > 0.05) the nitrogen intake and balance, but led to a greater (p 0.05) synthesis of microbial nitrogen. Microbial efficiency was not affected (p > 0.05), and showed an average value of 204.32 g microbial crude protein kg-1 total digestible nutrients.

Objetivou-se avaliar o efeito da utilização de cana-de-açúcar in natura, silagem de cana sem ou com Lactobacillus buchneri e cana queimada sem ou com L. buchneri sobre o comportamento ingestivo, balanço de nitrogênio e síntese de compostos nitrogenados microbianos em vacas lactantes. Foram utilizadas cinco vacas mestiças, ¾ Holandês x Gir, distribuídas em um quadrado latino 5 x 5 e alimentadas com dietas compostas por 60% de volumoso e 40% de concentrado na base da matéria seca, para atender um peso corporal médio de 550 kg e produção média de 15 kg de leite por dia. A cana-de-açúcar in natura proporcionou maiores valores (p 0,05) para eficiência de alimentação da matéria seca (3.133,3 vs 2.234,47 g MS h-1) e de ruminação (1.642,3 vs 1.222,93 g MS h-1) em relação às silagens. Observou-se menor tempo de mastigação total (58,7 vs 81,5 min. kg-1 de MS) para cana-de-açúcar in natura quando comparada às silagens sem inóculo. A utilização do aditivo microbiano na ensilagem da cana-de-açúcar não alterou (p > 0,05) o consumo e o balanço de nitrogênio, porém propiciou maior (p 0,05) síntese de nitrogênio microbiano. Não houve diferença entre as dietas (p > 0,05) para eficiência microbiana, cujo valor médio foi de 204,32 g PB microbiana kg-1 de TDN.

Assuntos

RESUMO

This study evaluated the effect of using fresh sugar cane, sugar cane silage with or without Lactobacillus buchneri, and burnt sugar cane silage with or without L. buchneri on ingestive behavior, nitrogen balance and synthesis of microbial nitrogen compounds of dairy cows. Five ¾ Holstein x Gir crossbred cows, assigned to a 5 x 5 Latin square design, were given diets with a 60:40 forage: concentrate ratio on a dry matter basis, to meet an average body weight of 550 kg and production of 15 kg of milk per day. The treatment with fresh sugar cane showed higher values (p 0.05) for dry matter feed efficiency (3,133.3 vs 2,234.47 g DM h-1) and rumination (1,642.3 vs 1,222.93 g DM h-1) compared to the silages. There was a shorter total chewing time (58.7 vs 81.5 min. kg-1 DM) for fresh sugar cane when compared to silages without inoculum. The addition of microbial additive during ensiling of sugar cane did not alter (p > 0.05) the nitrogen intake and balance, but led to a greater (p 0.05) synthesis of microbial nitrogen. Microbial efficiency was not affected (p > 0.05), and showed an average value of 204.32 g microbial crude protein kg-1 total digestible nutrients.(AU)

Objetivou-se avaliar o efeito da utilização de cana-de-açúcar in natura, silagem de cana sem ou com Lactobacillus buchneri e cana queimada sem ou com L. buchneri sobre o comportamento ingestivo, balanço de nitrogênio e síntese de compostos nitrogenados microbianos em vacas lactantes. Foram utilizadas cinco vacas mestiças, ¾ Holandês x Gir, distribuídas em um quadrado latino 5 x 5 e alimentadas com dietas compostas por 60% de volumoso e 40% de concentrado na base da matéria seca, para atender um peso corporal médio de 550 kg e produção média de 15 kg de leite por dia. A cana-de-açúcar in natura proporcionou maiores valores (p 0,05) para eficiência de alimentação da matéria seca (3.133,3 vs 2.234,47 g MS h-1) e de ruminação (1.642,3 vs 1.222,93 g MS h-1) em relação às silagens. Observou-se menor tempo de mastigação total (58,7 vs 81,5 min. kg-1 de MS) para cana-de-açúcar in natura quando comparada às silagens sem inóculo. A utilização do aditivo microbiano na ensilagem da cana-de-açúcar não alterou (p > 0,05) o consumo e o balanço de nitrogênio, porém propiciou maior (p 0,05) síntese de nitrogênio microbiano. Não houve diferença entre as dietas (p > 0,05) para eficiência microbiana, cujo valor médio foi de 204,32 g PB microbiana kg-1 de TDN.(AU)

Assuntos

RESUMO

O objetivo deste estudo foi avaliar a produção microbiana, produção, composição e perfil de ácidos graxos do leite de vacas alimentadas com rações contendo níveis crescentes de torta de girassol (TG). Foram utilizadas oito vacas da raça Girolando com peso médio de 515 kg. O delineamento experimental utilizado foi quadrado latino 4 x 4 duplo, em que os fatores foram níveis de inclusão de TG na ração concentrada (0; 7; 14 e 21%). Observou-se efeito linear decrescente para os teores de proteína, gordura do leite e N-ureico. Os teores de alantoína (mmol dia-1) foram influenciados pelos níveis de inclusão da TG, apresentando comportamento quadrático (p < 0,05). Os teores de acido úrico, purinas totais, purinas absorvidas, nitrogênio microbiano e síntese microbiana não foram influenciados (p > 0,05) pelos níveis de inclusão de TG. Foi observado efeito linear decrescente com a adição dos níveis de torta de girassol para o ácido palmítico (C16:0), para os demais ácidos graxos não foram observadas diferenças (p > 0,05). A utilização de torta de girassol pode consistir em alternativa na alimentação de vacas em lactação; contudo não altera a eficiência de síntese de proteína microbiana e o perfil de ácidos graxos do leite.

The objective of this study was to evaluate the microbial production, production, composition and fatty acids profile of milk from dairy cows fed rations with growing levels of sunflower cake. Eight Girolando cows were used, averaging 515 kg of body weight. The experimental design was a 4 x 4 Latin square, in duplicate, where the factors consisted of the rates of sunflower cake inclusion in the concentrate portion (0, 7, 14 and 21%). A decreasing linear effect was observed for protein and fat production in milk and N urea content. Allantoin rates (mmol day-1) were influenced by the levels of sunflower cake inclusion, with quadratic effect (p < 0.05). Uric acid, total purines, absorbed purines, microbial nitrogen and microbial synthesis were not affected (p > 0.05) by the levels of sunflower cake inclusion. A decreasing linear effect was observed with the levels of sunflower cake inclusion for palmitic acid (C16:0); no statistical differences were observed (p > 0.05) for the other fatty acids. The use of sunflower cake may represent an alternative feed for dairy cows, but does not alter the efficiency of microbial protein synthesis and fatty acids profile of milk.

Assuntos

RESUMO

The objective of this study was to evaluate the microbial production, production, composition and fatty acids profile of milk from dairy cows fed rations with growing levels of sunflower cake. Eight Girolando cows were used, averaging 515 kg of body weight. The experimental design was a 4 x 4 Latin square, in duplicate, where the factors consisted of the rates of sunflower cake inclusion in the concentrate portion (0, 7, 14 and 21%). A decreasing linear effect was observed for protein and fat production in milk and N urea content. Allantoin rates (mmol day-1) were influenced by the levels of sunflower cake inclusion, with quadratic effect (p 0.05). Uric acid, total purines, absorbed purines, microbial nitrogen and microbial synthesis were not affected (p > 0.05) by the levels of sunflower cake inclusion. A decreasing linear effect was observed with the levels of sunflower cake inclusion for palmitic acid (C16:0); no statistical differences were observed (p > 0.05) for the other fatty acids. The use of sunflower cake may represent an alternative feed for dairy cows, but does not alter the efficiency of microbial protein synthesis and fatty acids profile of milk.

O objetivo deste estudo foi avaliar a produção microbiana, produção, composição e perfil de ácidos graxos do leite de vacas alimentadas com rações contendo níveis crescentes de torta de girassol (TG). Foram utilizadas oito vacas da raça Girolando com peso médio de 515 kg. O delineamento experimental utilizado foi quadrado latino 4 x 4 duplo, em que os fatores foram níveis de inclusão de TG na ração concentrada (0; 7; 14 e 21%). Observou-se efeito linear decrescente para os teores de proteína, gordura do leite e N-ureico. Os teores de alantoína (mmol dia-1) foram influenciados pelos níveis de inclusão da TG, apresentando comportamento quadrático (p 0,05). Os teores de acido úrico, purinas totais, purinas absorvidas, nitrogênio microbiano e síntese microbiana não foram influenciados (p > 0,05) pelos níveis de inclusão de TG. Foi observado efeito linear decrescente com a adição dos níveis de torta de girassol para o ácido palmítico (C16:0), para os demais ácidos graxos não foram observadas diferenças (p > 0,05). A utilização de torta de girassol pode consistir em alternativa na alimentação de vacas em lactação; contudo não altera a eficiência de síntese de proteína microbiana e o perfil de ácidos graxos do leite.

RESUMO

The objective of this study was to evaluate the microbial production, production, composition and fatty acids profile of milk from dairy cows fed rations with growing levels of sunflower cake. Eight Girolando cows were used, averaging 515 kg of body weight. The experimental design was a 4 x 4 Latin square, in duplicate, where the factors consisted of the rates of sunflower cake inclusion in the concentrate portion (0, 7, 14 and 21%). A decreasing linear effect was observed for protein and fat production in milk and N urea content. Allantoin rates (mmol day-1) were influenced by the levels of sunflower cake inclusion, with quadratic effect (p 0.05). Uric acid, total purines, absorbed purines, microbial nitrogen and microbial synthesis were not affected (p > 0.05) by the levels of sunflower cake inclusion. A decreasing linear effect was observed with the levels of sunflower cake inclusion for palmitic acid (C16:0); no statistical differences were observed (p > 0.05) for the other fatty acids. The use of sunflower cake may represent an alternative feed for dairy cows, but does not alter the efficiency of microbial protein synthesis and fatty acids profile of milk.

O objetivo deste estudo foi avaliar a produção microbiana, produção, composição e perfil de ácidos graxos do leite de vacas alimentadas com rações contendo níveis crescentes de torta de girassol (TG). Foram utilizadas oito vacas da raça Girolando com peso médio de 515 kg. O delineamento experimental utilizado foi quadrado latino 4 x 4 duplo, em que os fatores foram níveis de inclusão de TG na ração concentrada (0; 7; 14 e 21%). Observou-se efeito linear decrescente para os teores de proteína, gordura do leite e N-ureico. Os teores de alantoína (mmol dia-1) foram influenciados pelos níveis de inclusão da TG, apresentando comportamento quadrático (p 0,05). Os teores de acido úrico, purinas totais, purinas absorvidas, nitrogênio microbiano e síntese microbiana não foram influenciados (p > 0,05) pelos níveis de inclusão de TG. Foi observado efeito linear decrescente com a adição dos níveis de torta de girassol para o ácido palmítico (C16:0), para os demais ácidos graxos não foram observadas diferenças (p > 0,05). A utilização de torta de girassol pode consistir em alternativa na alimentação de vacas em lactação; contudo não altera a eficiência de síntese de proteína microbiana e o perfil de ácidos graxos do leite.