Effects of polymer-coated slow-release urea on performance, ruminal fermentation, and blood metabolites in dairy cows

The aim of the present study was to evaluate effects of partial replacement of corn grain and soybean meal with whole raw soybean or whole cottonseed on milk yield and composition, digestibility, ruminal fermentation and blood metabolites. Eighteen multiparous Holstein cows (133.0 ± 53.1 days in milk, 585.2 ± 54.2 kg of BW and 32.22 ± 5.32 kg/day of milk) were used in six 3 × 3 Latin squares with 21-day periods. The cows were randomly assigned to receive one of the following diets: control (CT), diet without oilseed inclusion; whole soybean (WS), inclusion of 120 g/kg of whole raw soybean (diet DM basis); and whole cottonseed (WCS), inclusion of 120 g/kg of whole cottonseed (diet DM basis). Dietary supplementation with WS or WCS had no effect on milk yield and composition. DM and non-fibre carbohydrate intake were decreased in cows fed WS and WCS when compared with CT; however, WS and WCS increased ether extract intake and digestibility. The WCS decreased DM, crude protein, ether extract and non-fibre carbohydrate intake when compared with WS. Cows fed WCS had higher ruminal pH than those fed WS or CT. Cows fed WS showed higher propionate concentration than cows fed WCS. Ruminal ammonia nitrogen concentration decreased when cows were fed WS compared with those fed CT or WCS. The partial replacement of corn grain and soybean meal with WS or WCS in diets of mid-lactating dairy cows decreased DM intake and altered ruminal fermentation, but did not affect milk yield and composition.

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Effects of replacing soybean meal with slow-release urea on milk production of Holstein dairy cows

South African Journal of Animal Science ◽

10.4314/sajas.v51i1.6 ◽

2021 ◽

Vol 51 (1) ◽

Author(s):

S. Hallajian ◽

J. Fakhraei ◽

H.M. Yarahamdi ◽

K.J. Khorshidi

Keyword(s):

Fatty Acid ◽

Dairy Cows ◽

Milk Production ◽

Slow Release ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Milk Composition ◽

Plant Protein ◽

Low Density ◽

Slow Release Urea

The study investigated the effects of replacing soybean meal (SBM) with slow-release urea (SRU) on milk production, milk composition, and rumen fermentation of Holstein dairy cows. Sixteen Holstein cows weighing between 550 and 680 kg in mid lactation were randomly assigned to four dietary treatments in a 12-week study. The treatments consisted of T1: a diet containing 16.7% crude protein (CP), T2: T1 with 0.5% SRU replacing plant protein, T3: T1 with 0.75% SRU replacing plant protein, and T4: T1 with 1.00% SRU replacing plant protein. Animals were fed three times a day with feed being offered ad libitum. Dry matter intake (DMI) and average daily gain (ADG) were not affected by the level of SRU. Feeding SRU did not affect milk production and milk composition significantly, but milk fat and milk urea nitrogen (MUN) levels were increased. Significant differences were observed in ruminal volatile fatty acid (VFA) concentration. Feeding SRU increased butyrate concentration with no significant effects on concentrations of acetate or propionate. Significant differences were observed in cholesterol, triglyceride, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and nonesterified fatty acid (NEFA) concentrations, but glucose, very-low-density lipoprotein (VLDL) and β-hydroxybutyrate (BHB) levels were not affected significantly by the treatments. Thus, feeding SRU altered the release rate of ammonia and provided more ammonia nitrogen (NH3-N) for microbial protein synthesis in the rumen.

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Effect of dietary sugar concentration and sunflower seed supplementation on lactation performance, ruminal fermentation, milk fatty acid profile, and blood metabolites of dairy cows

Journal of Dairy Science ◽

10.3168/jds.2015-10565 ◽

2016 ◽

Vol 99 (5) ◽

pp. 3539-3548 ◽

Cited By ~ 4

Author(s):

A. Razzaghi ◽

R. Valizadeh ◽

A.A. Naserian ◽

M.Danesh Mesgaran ◽

A.J. Carpenter ◽

...

Keyword(s):

Fatty Acid ◽

Dairy Cows ◽

Fatty Acid Profile ◽

Sunflower Seed ◽

Sugar Concentration ◽

Blood Metabolites ◽

Milk Fatty Acid ◽

Ruminal Fermentation ◽

Lactation Performance ◽

Dietary Sugar

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Performance of lactating crossbred cows on pasture supplemented with conventional urea or slow release urea

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/1678-6701 ◽

2014 ◽

Vol 66 (5) ◽

pp. 1487-1494

Author(s):

D.C. Abreu ◽

R.P. Lana ◽

A.S. Oliveira ◽

F.A. Barbosa ◽

F.L. Andrade ◽

...

Keyword(s):

Dairy Cows ◽

Milk Production ◽

Rainy Season ◽

Crude Protein ◽

Dry Matter ◽

Slow Release ◽

Elephant Grass ◽

Productive Performance ◽

Slow Release Urea ◽

Matter Basis

The effect of using conventional urea (CU) or slow release urea (SRU) was evaluated by replacing soybean meal (SBM) in concentrated supplements in levels of 2, 4 or 6% (dry matter basis) on productive performance of crossbred Holstein x Zebu lactating dairy cows (499±61kg body weight and 167 days of lactation) grazing on elephant grass (11.5% CP and 60% NDF) under rotational grazing during the rainy season. A supplement control (no urea) was used containing SBM as a protein source. A total of 21 cows were distributed an incomplete randomized block design with three periods of 21 days each (14 days of adaptation and seven days of collection). The animals entered the paddocks with a pasture height of 110-120cm and left when the grass reached the height of 40-50cm. The concentrated isonitrogenous supplements (24% crude protein, dry matter basis) were provided in the amount of 3.2kg/cow/day (fed basis). There was no effect (P>0.05) on source of crude protein (SBM vs source NPN), source NPN, level of NPN, interaction between source NPN and level of NPN on milk production (10.0kg/day), fat milk production corrected to 3.5% (10.7kg/day), levels of fat (4.01%), protein (3.66%), lactose (4.16%), total solids (12.86%) and non-fat solids (8.60%) in milk. The replacement of CU by SRU does not promote improvement in the productive performance of crossbred dairy cows grazing on elephant grass during the rainy season. Urea (CU or SRU) can be included in up to 6% of the DM concentrated supplements, replacing SBM, without affecting the productive performance of crossbred cows (Holstein x Zebu) in pasture during the rainy season.

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