<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>The present experiment aimed to evaluate the effect of partial replacement of corn with chocolate byproducts, protected fats, or their mixture supplemented with zinc in the diet of lactating cows on feed utilization and lactation performance for 90 days. Fifty multiparous Holstein cows (565±25 kg BW, 3±1 parity, 7±1 days in milk, and a previous milk production of 35±2.9 kg/d), were randomly assigned to 5 treatments in a completely randomized design. The control diet contained (per kg DM): 412 g concentrate feed mixture, 412 g corn silage, and 176 g berseem hay. The control diet was supplemented with 1 g of zinc daily (Zinc diet). In the other diets, each kg of crushed corn grain was replaced with (DM basis) 600 g chocolate byproducts (CH diet), 400 g protected fats (PF diet), or 500 g of chocolate byproducts and protected fats mixture (1:1 DM basis) (CHPF diet). Both amounts of protected fats and chocolate byproducts had the same energy concentration as 1 kg of corn. The total mixed ration was prepared and distributed using a horizontal mixer system after mixing for 20 min. Chemical analysis showed that the replacement minimally affected the composition of the total mixed rations. Additionally, treatments did not affect feed intake. Compared to the control treatment, the zinc treatment did not affect milk production, milk composition, or feed efficiency. Increased (P&lt;0.05) daily production of milk and component yields, and feed efficiency as well as fat concentration were observed by the CH, PF and CHPF treatments. Without affecting other measured blood parameters or hematocrit, treatments increased (P&lt;0.05) the concentrations of total proteins, albumin, glucose, cholesterol, triglyceride, and zinc in the blood of cows. Additionally, the CH, PF, and CHPF treatments increased (P&lt;0.01) the digestibility of nutrients compared to the control treatment. It is concluded that the addition of zinc to the control did not affect cow performance; however, its addition to chocolate byproducts, protected fats, or their mixture to partially replace corn improved the performance of cows.</p>
</abstract>

The present experiment aimed to evaluate the effect of partial replacement of corn with chocolate byproducts, protected fats, or their mixture supplemented with zinc in the diet of lactating cows on feed utilization and lactation performance for 90 days. Fifty multiparous Holstein cows (565±25 kg BW, 3±1 parity, 7±1 days in milk, and a previous milk production of 35±2.9 kg/d), were randomly assigned to 5 treatments in a completely randomized design. The control diet contained (per kg DM): 412 g concentrate feed mixture, 412 g corn silage, and 176 g berseem hay. The control diet was supplemented with 1 g of zinc daily (Zinc diet). In the other diets, each kg of crushed corn grain was replaced with (DM basis) 600 g chocolate byproducts (CH diet), 400 g protected fats (PF diet), or 500 g of chocolate byproducts and protected fats mixture (1:1 DM basis) (CHPF diet). Both amounts of protected fats and chocolate byproducts had the same energy concentration as 1 kg of corn. The total mixed ration was prepared and distributed using a horizontal mixer system after mixing for 20 min. Chemical analysis showed that the replacement minimally affected the composition of the total mixed rations. Additionally, treatments did not affect feed intake. Compared to the control treatment, the zinc treatment did not affect milk production, milk composition, or feed efficiency. Increased (P<0.05) daily production of milk and component yields, and feed efficiency as well as fat concentration were observed by the CH, PF and CHPF treatments. Without affecting other measured blood parameters or hematocrit, treatments increased (P<0.05) the concentrations of total proteins, albumin, glucose, cholesterol, triglyceride, and zinc in the blood of cows. Additionally, the CH, PF, and CHPF treatments increased (P<0.01) the digestibility of nutrients compared to the control treatment. It is concluded that the addition of zinc to the control did not affect cow performance; however, its addition to chocolate byproducts, protected fats, or their mixture to partially replace corn improved the performance of cows.

Enrichment of chocolate byproducts and protected fats with zinc to partially replace corn in diets of early lactation Holstein cows

Animal Production Department, Faculty of Agriculture

Annals of Animal Science

This work is licensed under the Creative Commons Attribution 4.0 International License.

The present experiment aimed to evaluate the effect of partial replacement of corn with chocolate byproducts, protected fats, or their mixture supplemented...

Enrichment of chocolate byproducts and protected fats with zinc to partially replace corn in diets of early lactation Holstein cows

Published Online: Jul 26, 2023

Page range: 789 - 798

Received: Dec 25, 2022

Accepted: Jan 20, 2023

DOI: https://doi.org/10.2478/aoas-2023-0012

Keywords
chocolate byproducts, corn, energy feeds, milk production, protected fats, zinc

© 2023 Mohammed H. Bakr et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Enrichment of chocolate byproducts and protected fats with zinc to partially replace corn in diets of early lactation Holstein cows

Published Online: Jul 26, 2023

Page range: 789 - 798

Received: Dec 25, 2022

Accepted: Jan 20, 2023

DOI: https://doi.org/10.2478/aoas-2023-0012

Keywordschocolate byproducts, corn, energy feeds, milk production, protected fats, zinc

© 2023 Mohammed H. Bakr et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Keywords
chocolate byproducts, corn, energy feeds, milk production, protected fats, zinc