Comparison of feeding diets diluted with sorghum-sudangrass silage or low-quality grass on nutrient intake and digestibility and growth performance of Holstein dairy heifers

Abstract

This study was carried out to evaluate the nutrient intakes and growth of dairy heifers offered an alfalfa silage-corn silage diet (CON; 14.3% crude protein, 61.1% total digestible nutrients, 47.9% neutral detergent fiber) compared with diets containing 1 of 2 types of sorghumsudangrass (SS) silages: conventional or photoperiod sensitive. The objective of the study was to determine the potential to use SS to control dry matter (DM) and nutrient intakes and weight gain. Both diets were similar in nutrient composition, with approximately 13% crude protein, 60 to 61% total digestible nutrients, and 55% neutral detergent fiber. Seventy-two Holstein heifers (16-18 mo at study initiation) were blocked by initial body weight (light = 422 ± 12.8 kg; medium = 455 ± 14.8 kg; heavy = 489 ± 16.7 kg) with 3 pens assigned to each weight block (8 heifers/pen; 24 heifers/block). The 3 diets were randomly allocated to the pens within each block and offered for 12 wk. Heifers offered the CON diet had greater DM, protein, and energy intakes compared with those offered the SS silage-based diets due to the greater neutral detergent fiber concentration of the SS diets. With lower DM and nutrient intakes, average daily gain was in the recommended range (0.8-1 kg/d for Holstein heifers) for heifers offered the SS silage-based diets (mean of 0.92 kg/d for both SS diets vs. 1.11 kg/d for CON). Sorting behaviors for heifers offered both SS diets were more aggressive against long, medium, and short particles compared with those of heifers offered the CON diet; however, heifers sorted large particles from photoperiod-sensitive silage more aggressively than those from conventional silage. Based on this study, SS silage-based diets can control the DM and energy intakes for heifers and maintain optimum growth rates, with harvesting at a shorter chop length likely helping to alleviate sorting issues.

Effect of diet energy level and genomic residual feed intake on bred Holstein dairy heifer growth and feed efficiency

“…When calculated on a % of BW basis, NDF intake was close to 1% of BW (0.95-0.99% of BW as NDF), which is consistent with the work by Hoffman et al (2008) that found heifers eat approximately 1.0% of BW in NDF daily when offered high forage diets at ad libitum intakes. Several other studies with feeding higher fiber, lower energy diets for ad libitum intakes have also shown reduced intakes of DM and energy similar to our results (Greter et al, 2008;Coblentz et al, 2012Coblentz et al, , 2015Su et al, 2017;Li et al, 2019b). Starch intake was greater (P < 0.01) for heifers fed the HE diet (1.7 kg/d) compared with the LE diet (1.1 kg/d), primarily because there was a greater amount of corn silage in the HE diet.…”

“…The current study had lower DMI and energy intakes for both diet treatment groups ( 10 2001) predictions for a 520 kg of BW heifer (average of initial and final study weights) at 150 d pregnant were 12.7 kg of DMI, and 25.9 Mcal of ME for 0.9 kg of gain/d and 29.6 Mcal of ME for 1.17 kg of gain/d. As discussed previously, we have observed this in the freestall facility for previous studies (Coblentz et al, 2015;Su et al, 2017;Li et al, 2019b) and may be due to reduced energy use for exercise and reduced maintenance requirements in freestall or other confinement situations in which heifers have feed access and laying space in a small pen and have minimal environmental stress (Fox and Tylutki, 1998).…”

“…Furthermore, the inclusion of the diluents in the diet reduced energy content of the LE diet (57.0% TDN and 2.18 Mcal of ME/kg) compared with HE (62.7% TDN and 2.39 Mcal of ME/kg). The energy level for HE would be considered above requirements for heifers of this BW and days pregnant using NRC (2001) estimates for DMI and energy needs, and based on previous results in our freestall facility (Coblentz et al, 2015;Su et al, 2017;Li et al, 2019b). Current NRC (2001) DMI predictions for heifers are greater than expected based on these previous results in our facility, especially when feeding higher fiber diets than what we used in this study.…”

“…Dietary dilution is another management practice that has proven successful in reducing caloric intake by substituting a higher fiber, lower digestibility forage such as straw, warm-season perennial grasses, lowquality hay, sorghum forages, or corn stover for some of the high-quality forages (primarily corn silage and alfalfa silage) when offered at ad libitum intakes (Coblentz et al, 2012;Su et al, 2017;Li et al, 2019b). Using this feeding practice, dairy producers are able to potentially reduce feed costs by controlling feed intakes, utilize lower-cost forages, and provide heifers with opportunities to express natural foraging behavior (Greter et al, 2008).…”

Effects of fermented feed of Pennisetum giganteum on growth performance, oxidative stress, immunity and gastrointestinal microflora of Boer goats under thermal stress

“…Moreover, due to its strong stress resistance, high temperature resistance, drought resistance, salt and alkali resistance, P. giganteum is easy to plant with high yield, which can effectively improve the shortage of forage resources and further reduce the feed grain ( Hayat et al, 2020 ; Li et al, 2020 ). It has been shown that P. giganteum can replace corn silage, Sorghum sudanense and other conventional forages as livestock feed ( Li et al, 2019 ). Therefore, P. giganteum is the best choice for high-quality feed for animal husbandry.…”