Effects of dry matter intake restriction on diet digestion, energy partitioning, phosphorus retention, and ruminal fermentation by beef steers

Abstract There is a lack of consistency across the globe in how countries establish tissue ractopamine residue limits and which residue limits are applied to various tissues, particularly for edible noncarcass tissues. Therefore, some US beef slaughter organizations have recommended a 48-h voluntary removal of ractopamine before slaughter in order to meet residue requirements of specific export countries and maintain international trade. Our objective was to assess the impact of voluntary removal of ractopamine hydrochloride (Optaflexx®; Elanco, Greenfield, IN) up to 8 d before slaughter on growth performance and carcass characteristics. Crossbred beef steers (60 pens of 10 animals/pen) with an initial shrunk body weight (BW) of 611.8 ± 10 kg SEM were fed one of six treatments over 42 d. Treatments included a control that did not receive ractopamine, on-label use of ractopamine (0-d withdrawal), and 2, 4, 6, or 8 d of voluntary removal of ractopamine from feed before slaughter. The start of ractopamine feeding (30.1 mg/kg of diet dry matter for 32 d) was staggered so that blocks could be slaughtered on the same day. Dry matter intake was decreased by 0.5 kg/d when ractopamine was fed with a 0-d withdrawal (P = 0.04) compared to the control, but was not altered (P = 0.56) as the duration of ractopamine removal increased from 0 to 8 d. Final BW, total BW gain, and average daily BW gain were increased by feeding ractopamine with a 0-d withdrawal (P = 0.09) compared to the control, but these variables decreased in a linear manner (P = 0.10) as the duration of removal increased from 0 to 8 d. Gain efficiency was improved by 15% (P < 0.01) by feeding ractopamine with a 0-d withdrawal compared to the control, and gain efficiency decreased linearly (P = 0.06) as the duration of ractopamine removal increased. Approximately 2/3 of the increase in gain efficiency remained after 8 d of removal. Hot carcass weight was increased by 6 kg (P = 0.02) by feeding ractopamine with a 0-d withdrawal compared to the control. Measured carcass characteristics were not altered by ractopamine feeding or by removal before slaughter (P ≥ 0.24). The consequences of voluntary removal of ractopamine up to 8 d before slaughter were a linear decrease in live BW gain (0.64 kg/d), poorer gain efficiency, and numerically lighter carcass weight.

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UTILIZATION OF GRASS SILAGE BY CATTLE: EFFECT OF BARLEY AND FISHMEAL SUPPLEMENTS

Canadian Journal of Animal Science ◽

10.4141/cjas85-105 ◽

1985 ◽

Vol 65 (4) ◽

pp. 897-903 ◽

Cited By ~ 12

Author(s):

D. M. VEIRA ◽

M. IVAN ◽

G. BUTLER ◽

J. G. PROULX

Keyword(s):

Formic Acid ◽

Nitrogen Content ◽

Dry Matter ◽

Dry Matter Intake ◽

Beef Steers ◽

Large Reduction ◽

High Nitrogen Content ◽

High Nitrogen ◽

Grass Silage ◽

Ad Libitum

Following weaning at 6–7 mo of age, 36 beef steers were used to determine production responses when grass silage was supplemented with barley or fishmeal. The silage was made from direct-cut, formic- acid-treated grass harvested from a mixed sward and had a high nitrogen content but poor fermentation characteristics. The silage was fed ad libitum for 98 days either alone or supplemented with 500 g fishmeal or 500 g barley per day. Both fishmeal and barley increased total dry matter intake (P < 0.01) by an amount equivalent to the quantity of supplement offered but had no effect on silage intake (P > 0.05). Steers fed the fishmeal grew substantially faster than either the barley (0.53 kg/day) or unsupplemented (0.54 kg/day) groups (P < 0.01). Fishmeal supplementation resulted in a large reduction (35%) in the amount of feed required per kilogram of gain. Key words: Cattle, grass silage, fishmeal, growth

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Effects of roughage type on particle separation, rumination, fiber mat characteristics, in situ degradation, and ruminal fermentation parameters in beef steers

Journal of Animal Science ◽

10.1093/jas/skab214 ◽

2021 ◽

Author(s):

Catherine L Lockard ◽

Caleb G Lockard ◽

Wyatt N Smith ◽

Kendall J Karr ◽

Ben P Holland ◽

...

Keyword(s):

Dry Matter ◽

Rumen Fluid ◽

Fluid Collection ◽

Latin Square ◽

Experimental Unit ◽

Beef Steers ◽

Ruminal Fermentation ◽

In Situ Degradation ◽

Fermentation Parameters

Abstract Six ruminally cannulated steers (average BW = 791 + 71 kg) were used in a replicated 3 × 3 Latin square experiment to determine the effects of roughage type on rumination, fiber mat characteristics, and rumen fermentation variables. Three roughages were included at 7% (DM basis) in a steam flaked corn-based diet; cotton burrs (CB), wheat silage (WS), or corn stalks (CS). Steers were fitted with a sensory collar to record rumination behaviors in 2-h intervals at the beginning of the experiment. Each 30-d period consisted of a 7-d of recovery, 14-d of diet adaptation, 7-d of rumination data collection (daily and bi-hourly average rumination), 1-d of rumen fluid collection, and 1-d of rumen evacuations. In situ degradation of individual roughages was determined for 4-d after period 3 evacuations. During rumen evacuations, ruminal contents were removed; the rumen fiber mat (RF) was separated from the liquid portion with a 2 mm sieve, weighed, and a subsample was dried. Data were analyzed using the MIXED procedure of SAS with steer as the experimental unit and roughage (CB, WS, and CS) as the main effect. Dry matter intake (DMI) was not different for CB and WS (P = 0.25) and greatest for steers consuming CS diet (P < 0.01). Roughage type did not influence the weight of the RF dry matter (%; DM; P = 0.92), RF weight (P = 0.69), or RF:DMI ratio (P = 0.29). Daily rumination (min/d) did not differ among roughages (P = 0.40), but min of rumination/kg of DMI was greatest for CS (18.0 min), min/kg of NDF was greatest for WS (89.8 min; P = 0.02), and min/kg of peNDF was greatest for CS (132.4 min; P < 0.01). Wheat silage had the greatest percentage of soluble DM and CB-R and CS-R (P < 0.01) had the greatest ruminal degraded DM fraction. Rumen fiber mat did not differ for roughages, although rumination min/kg of DMI and peNDF was greatest for steers consuming CS and WS. In situ degradation determined that CB-R and CS-R had the greatest percentage of ruminal degraded DM. Based on the objective of the experiment, roughage type did not influence daily rumination or fiber mat characteristics.

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PSXII-18 The influence of molybdenum in drinking water or feed on apparent absorption and retention of molybdenum and copper in beef steers

Journal of Animal Science ◽

10.1093/jas/skz258.840 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 423-424

Author(s):

Meghan P Thorndyke ◽

Nicole M Tillquist ◽

Nicole M Jones ◽

Terry Engle

Keyword(s):

Drinking Water ◽

Dry Matter ◽

Block Design ◽

Sodium Molybdate ◽

Mixed Effects ◽

Dry Matter Intake ◽

Beef Steers ◽

Apparent Absorption ◽

Randomized Block Design ◽

Intake Control

Abstract Twelve Angus steers (BW 694.1 ± 47.4 kg) fitted ruminal cannulae were used to examine the effect of molybdenum (Mo) supplemented in drinking water or feed on apparent absorption and retention of Mo and copper (Cu). Steers were fed a low-quality grass hay diet (DM basis: 6.5% CP; 0.13% S, 3.4 mg Cu/kg, 2.4 mg Mo/kg) for 14 d. Steers were then housed in individual metabolism stalls for 3 d to determine DMI. Steers were then blocked by BW and DMI and randomly assigned within block to one of three treatments (n = 4 steers per treatment). Treatments consisted of: 1) Control (no supplemental Mo); 2) 5.0 mg Mo/kg DM from sodium molybdate dihydrate (Mo-diet), and 3) 1.5 mg Mo/l from sodium molybdate dihydrate delivered in the drinking water (Mo-water). After the 3d DMI determination period, total fecal and urine output was collected for 5 d. Dry matter intake and DM digestibility were similar across treatments. Data were analyzed using a mixed effects model (PROC MIXED, SAS) for a completely randomized block design. Apparent absorption of Cu was greater (P < 0.05) in Control and Mo-water steers when compared to Mo-diet steers. Apparent retention of Cu was greater (P < 0.05) in Control steers when compared to Mo-diet steers. Steers receiving Mo-water had a similar apparent retention of Cu when compared to Control and Mo-diet steers. By design, treatment was a significant (P < 0.01) source of variation for Mo intake. Control steers had lesser (P < 0.05) Mo intake when compared to Mo-diet and Mo-water supplemented steers. Apparent absorption and retention of Mo were greater (P < 0.05) in Mo-diet steers compared to Control and Mo-water steers. These data indicate that Mo metabolism and apparent absorption of Cu are different when Mo is supplemented in water relative to feed.

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Studies on the supplementary feeding of sheep consuming mulga (Acacia aneura). 3. The provision of phosphorus, molasses and urea supplements under pen conditions

Australian Journal of Experimental Agriculture ◽

10.1071/ea9760818 ◽

1976 ◽

Vol 16 (83) ◽

pp. 818 ◽

Cited By ~ 5

Author(s):

NP McMeniman

Keyword(s):

Specific Gravity ◽

Dry Matter ◽

Unit Volume ◽

Phosphorus Content ◽

Nitrogen Retention ◽

Supplementary Feeding ◽

Dry Matter Intake ◽

Phosphorus Retention ◽

Acacia Aneura

Mulga (Acacia aneura) was fed to five groups of four weaner wethers. One group was given a supplement of phosphorus (P) as NaH2PO4, another energy as molasses (E), a third both phosphorus and molasses (P + E) and the fourth urea, phosphorus and molasses (P + E + N) ; the fifth group acted as an unsupplemented control (C). Total dry matter intake during the 42 weeks of the experiment was progressively increased by the addition of P, E, P + E and P + E + N to the diet. Liveweight gain was highest inthe P + E + Ngroup followed by the P + Egroupandthen the E group. Groups P and C lost weight during the experiment. Balance studies showed that P + E and P + E + N supplementation enhanced nitrogen retention, and phosphorus supplementation increased phosphorus retention. The digestibility of mulga was increased by phosphorus supplementation. Specific gravity and phosphorus content per unit volume of bone were increased by supplementation with P + E + N and P + E, and phosphorus content was marginally increased by P supplementation.

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Supplementary effect of peppermint (Mentha�נpiperita) on dry matter intake, digestibility, ruminal fermentation and milk production in early lactating dairy cows

Animal Science Journal ◽

10.1111/j.1740-0929.2006.00378.x ◽

2006 ◽

Vol 77 (5) ◽

pp. 503-509 ◽

Cited By ~ 17

Author(s):

Kenji HOSODA ◽

Hiroki MATSUYAMA ◽

Woong-Yeoul PARK ◽

Takehiro NISHIDA ◽

Motohiko ISHIDA

Keyword(s):

Dairy Cows ◽

Milk Production ◽

Dry Matter ◽

Dry Matter Intake ◽

Ruminal Fermentation ◽

Lactating Dairy Cows

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Effect of Forage:Concentrate Ratios in the diet and Intake Restriction on the Rumen Fermentation and Hormone Profiles of Finishing Beef Steers.

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s0308229600026167 ◽

1994 ◽

Vol 1994 ◽

pp. 69-69

Author(s):

C.L. Thorp ◽

R.W.J. Steen ◽

A.R.G. Wylie ◽

J.D. McEvoy ◽

C. Shaw

Keyword(s):

Growth Factor ◽

Beef Cattle ◽

Energy Intake ◽

Dry Matter ◽

Rumen Fermentation ◽

Fat Content ◽

Carcass Composition ◽

Dry Matter Intake ◽

Beef Steers ◽

Reducing Energy

Studies have shown that reducing energy intake by restricting dry matter intake (DMI) at a constant forage: concentrate (F:C) ratio is more effective at increasing carcass lean and reducing carcass fat content than is reducing energy intake by increasing the F:C ratio (1). Research at this Institute has also shown that, per megajoule of digestible energy (DE), diets restricted in this manner are 45 % more efficient at producing carcass lean.The mechanism by which these methods of restriction result in these differences in carcass composition has previously been assumed to be that of rumen fermentation. More recently however, the significance of rumen fermentation in controlling the carcass composition of beef cattle has been questioned (2,3).The aim of this experiment was to examine the effect of decreasing the F:C ratio, at constant DE and DMI, on both rumen and endocrinological parameters, in particular the hormones insulin and insulin like growth factor-1 (IGF-1), in finishing beef steers.

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