Feedlot System Research Articles

Evaluation of productive parameters of crossbred cattle finished in feedlot fed different diets with grain corn

The objective of the present experiment was to evaluate the influence of maize grain supply on animal performance of beef cattle in feedlot system to evaluate the average weight gain (ADG - kg/day, hot carcass weight (HCW) and hot carcass dressing (HCD, %). Twenty-five crossbred cattle in finished for 65 days, separated according to feeding, sex, castrated or bulls, comprising four different treatments: T1: 10 bulls fed a restrictive grain corn diet; T2: 4 bulls, fed on corn, forage and CT600, T3: 5 steers fed grain corn, forage and protein, and T4 5 cows fed corn, forage and protein. The T1 group presented higher values of ADG (1.32 kg/day), HCW (113.13 kg) and HCD (50.42%). The use of maize grain feed is efficient for bulls even in SRD breeds in feedlot, presenting satisfactory results in productive income.

Economic impacts of space allowance per animal on beef cattle feedlot

The objective of this study was to assess the economic outcomes of three space allowances (6, 12, and 24 m2 per animal) for outdoor feedlots-finished beef cattle. Simulations considered confinement systems with a static capacity of 5,000 animals per cycle and two 86-day cycles per year. Performance data were obtained from 1,350 uncastrated bovine males. An increase in space allowance elevated the fixed cost per animal. Fixed and variable costs represented 3% and 93% of the total operating cost, respectively. For variable costs, around 70% was used for purchasing cattle and 17% for purchasing feed. The operating profit per animal increased as space allowance increased (R$ 80.90, R$ 102.00, and R$ 109.00 for 6, 12, and 24 m2 per animal, respectively). The three feedlot systems recovered the initial investment and had a positive net present value. In addition, the internal rates of return were 22%, 27%, and 25%, and the probabilities of financial loss were 33%, 29%, and 26% for pen sizes of 6, 12, and 24 m2 per animal, respectively. Therefore, larger space allowances improve profitability and reduce the risk of financial loss.

Growth performance parameters, carcass traits, and meat quality of lambs supplemented with zinc methionine and (or) zinc oxide in feedlot system

Zinc (Zn) is a micromineral with structural, catalytic, and regulatory functions in muscle tissue. It improves growth in ruminants because it modulates energy metabolism. The objective of this stud...

Performance of feedlot cattle with inclusion of live yeast in the diet

The objective of this study was to evaluate the productive performance, ingestive behavior, apparent digestibility of the diet, rectal temperature, superficial thermography of skin and hull, and the carcass traits of heifers finished in confinement under the effect of inclusion of live yeasts (Saccharomyces cerevisiae as probiotic) in the diet. The treatments were: Control: diet without the inclusion of live yeasts, and Yeast: diet with the inclusion of live yeasts (7 g animal day-1, at the concentration of 107 CFU g-1. The diets were composed of corn silage at a constant forage: concentrate ratio of 50: 50, on a dry matter basis. The experimental design was completely randomized, composed of two treatments and nine replicates, wherein each replicate was represented by a stall with two animals. Thirty-six heifers, ½ blood Angus, from the same herd, with an average age of 11.9 months and an initial average body weight of 317 kg, were used in the experiment. Supplementation of live yeasts in the diet for finishing heifers proved to be efficient in the feedlot finishing phase because it provided improvement in the apparent digestibility of DM. In relation to the productive performance, ingestive behavior, rectal temperature, superficial thermography of skin and hull and carcass traits, no statistical difference was found between the treatments. The animals have already come from the property adapted to the feedlot system, defining small challenge against the presence of live yeasts included in the experimental diet, justifying the lack of expression on some results obtained.

Effect of alternating total mixed ration and pasture feeding on the fatty acid content and health indices of Jersey and Fleckvieh x Jersey milk

Certain fatty acids (FAs), such as omega-3 and conjugated linoleic acid (CLA) are considered essential FAs with beneficial health effects for humans. Milk is considered a relatively inexpensive and readily available source of these FAs and is part of a recommended healthy daily diet. The aim of the study was to determine the effect of diet changes on the FA composition of Jersey (J) and Fleckvieh x Jersey (FxJ) milk. Cows were alternately put on kikuyu-ryegrass pasture, followed by a feedlot system, then returned to kikuyu-ryegrass pasture for four weeks each. The same concentrate mixture was fed to cows regardless of feeding system. The feedlot system consisted of a partial total mixed ration (pTMR). Milk samples were collected two and four weeks after diet changes and stored at −20 °C until laboratory analysis by gas chromatography. The FA concentration of milk was not affected by breed, although it was affected significantly by diet changes. Most notably, the total omega-3 and -6 FAs decreased when cows were fed pTMR while increasing when the diet was changed back to pasture feeding. The CLA content of milk was similarly affected. That is, concentrations decreased significantly when the cows were on the pTMR diet and increased when cows were put back on the pasture-based diet. The results suggested that the health benefits of milk fat are affected negatively when cows are fed pTMR compared with being fed in a pasture-based system. The health benefits of milk are reduced owing to decreased levels of the CLA content of milk fat. Therefore, feeding additional hay in a pasture-based production system should be reconsidered when aiming to produce milk that provides health beneficial qualities. Keywords: breed, diet, n-3 fatty acid, n-6 fatty acid, pasture, Fleckvieh

Land and Water Usage in Beef Production Systems.

Simple SummaryConsumers increasingly demand sustainable food production, including using world resources efficiently, avoiding environmental damage and ensuring good welfare of animals. Reports have suggested that beef production is costly in relation to world resource use and greenhouse gas production, so some consumers avoid beef. However, many reports refer mainly to feedlot systems. Ruminants can eat leaves that humans cannot eat, so if they are not fed grain, systems can be sustainable and valuable. This paper presents an analysis of the production of beef comparing all aspects of the use of land and conserved water for four production systems. It is suggested that conserved water use is a useful measure. Land use was the highest in extensive unmodified pasture systems, especially if the land became degraded. Less land was used in both feedlot and fertilised pasture systems and much less in semi-intensive silvopastoral systems. Conserved water use was the highest in feedlot systems, partly because of the grain fed to the cattle, lower in pasture systems and lowest in semi-intensive silvopastoral systems. This research indicates that, when beef production systems are being selected or consumers are deciding which beef to buy, extensive systems that degrade the land should be avoided, and well-managed extensive systems, especially semi-intensive silvopastoral systems, should be preferred to feedlot systems.This analysis, using published data, compared all land and conserved water use in four beef production systems. A widespread feedlot system and fertilised irrigated pasture systems used similar amounts of land. However, extensive unmodified pasture systems used three times more land, and semi-intensive silvopastoral systems used four times less land, so the highest use was 13 times the lowest. The amount of conserved water used was 64% higher in feedlots with relatively intensive rearing systems than in fertilised irrigated pasture; in extensive unmodified pasture systems, it was 38% and in semi-intensive silvopastoral systems, it was 21% of the fertilised irrigated pasture value, so the highest use was eight times the lowest. If there was no irrigation of pasture or of plants used for cattle feed, the feedlot water use was 12% higher than the fertilised pasture use and 57% higher than that in semi-intensive silvopastoral systems. These large effects of systems on resource use indicate the need to consider all systems when referring to the impact of beef or other products on the global environment. Whilst the use of animals as human food should be reduced, herbivorous animals that consume food that humans cannot eat and are kept using sustainable systems are important for the future use of world resources.

Performance, rumen fermentation, and gastrointestinal microflora of lambs fed pelleted or unpelleted total mixed ration

The objectives of this study were to evaluate the effects of feeding pelleted total mixed ration (PTMR) on growth performance, ruminal fermentation characteristics, and gastrointestinal microflora of fattening lambs. A total of 100 crossbred (Dorper sheep × Small-tail Han Sheep, DH) ram lambs at 120 d age with similar body weight (BW, 34.9 ± 0.5 kg) were randomly allocated to 10 pens. The pens were randomly assigned to 2 treatments with 5 replicates per treatment. Dietary treatments were PTMR and un-pelleted total mixed ration (UPTMR) with the same dietary ingredients and nutritional contents. The average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were determined in a 32-d experimental period. Ruminal pH, volatile fatty acid (VFA) concentrations, microbes in the rumen and cecum, and carcass weight were measured at the end of the experiment. Lambs fed PTMR had a greater ADFI (P = 0.002) than these fed UPTMR, greater ADG (P = 0.003) and carcass yield (P = 0.003) than that fed UPTMR. However, no significant difference was observed on FCR (P = 0.259) between the two groups of lambs. Compared with UPTMR treatment, feeding PTMR increased acetate and propionate concentrations, while decreased acetate to propionate ratio in the rumen (P < 0.05). Feeding PTMR increased the relative abundance of Prevotellaceae (P < 0.05) and decreased the relative abundance of Ruminococcaceae (P < 0.05) in the rumen, and increased the relative abundance of Bacteroidales (P < 0.05) and decreased the relative abundance of Lachnospiraceae, Clostridiales and Erysipelotrichales (P < 0.05) in the cecum relative to that of UPTMR group. In conclusion, feeding PTMR improved the growth performance and carcass yield of fattening lamb, primarily due to improvements in ADFI and ruminal fermentation characteristics through changing the structure and abundance of ruminal beneficial microbiota in fattening lambs. Thus, it is a feasible strategy to feed PTMR to fattening lambs in the intensive feed-lot style feeding system.

Parâmetros na utilização de silagem de grão úmido de milho na bovinocultura de corte

Objetivou-se, por meio do presente trabalho, reunir aporte teórico, via revisão da literatura, sob alguns parâmetros na utilização de silagem de grão úmido de milho referentes à bovinocultura de corte. Demonstrando as perspectivas de produção e importância que o milho representa para a alimentação animal. Com uma crescente demanda na produção de milho a fim de atender as necessidades do crescimento de sistemas de confinamentos, somam fatores que contribuem com maior importância na utilização de grãos na elaboração de dietas na bovinocultura, sendo considerado como a principal fonte de energia em dietas de bovinos de corte. Visto que o cenário da produção de carne bovina se torna cada vez mais competitivo, demostrando sua eficiência na digestibilidade e elevando os índices de produção, apresentando resultando satisfatórios referentes à eficiência alimentar e composição da carcaça como força de cisalhamento, pH, cor, maciez sensorial, suculência e sabor da carne e aumento no teor de lipídios na carne dos animais que recebem dietas de silagem de grão úmido de milho, além de reduzir o dispêndio no transporte e armazenamento, concentrando a operação de moagem. Assim, a presente revisão versa sobre a viabilidade da utilização da silagem de grão úmido de milho, por se tratar de umas da poucas praticas que consegue reunir baixos custos em relação a silagem de milho convencional, aliada a elevada qualidade nutricional, sobretudo com alta resposta animal, com o objetivo de maximizar a digestibilidade do amido, sendo esta a característica de maior evidencia.

Influence of lamb finishing system on animal performance and meat quality

This study aimed to assess the influence of lamb finishing systems on zootechnical performance, as well as on carcass and meat quality. The experiment was conducted at the APTA’s experimental farm. Thirty-three lambs were used – both sexes, initial age of 90 ± 3 days, Texel with Santa Inês, each animal being one experimental unit, with 6 males and 5 females per treatment. Treatments consisted of: lambs finished on pasture, in semi-feedlot or in feedlot. The lambs were slaughtered with average live weight of 35 kg. Weight gain and carcass measures were taken by ultrasound. After slaughter, carcass conformation and yield, pH, temperature, color, water retention capacity and tenderness were measured. Animals finished on pasture had lower weight gain, were slaughtered at an older age, with lighter carcass weight, smaller loin area, lower shank compactness index, besides lighter shoulder and shank weights, compared to the other production systems (p &lt; 0.05). There was no difference between the semi-feedlot and the feedlot systems for the assessed characteristics. In conclusion, production systems affect animal performance, as well as carcass and meat quality, especially when it comes to important production aspects, such as slaughter age and yield of premium cuts.

Organic additives used in beef cattle feedlot: Effects on metabolic parameters and animal performance.

Organic additives are recently being used in animal diets owing to their ability to control metabolic issues and result in better animal performance. Specifically, the organic additive Fator P® presents an additional advantage that is to cause a lesser greenhouse gas emission. This study evaluated whether Fator P® intake changes ruminal parameters or animal performance of beef cattle. Evaluations were carried out in a feedlot experiment divided into growing (46 days; two diets [control mix—CM and standard mix—SM] and finishing (lasted 83 days; four diets: CM, SM, Fator P® + virginiamycin, and Fator P® alone [FP]) trials. Animal performance study involved 48 animals allocated to 12 collective pens in completely randomized experimental design. Ruminal parameters were evaluated in separate metabolism study developed carried out using individual pen with four steers. During growing trial, FP diet resulted in higher (p < 0.05) dry matter intake (DMI) and ruminating time. In the finishing trial, diets containing Fator P® resulted in higher DMI than obtained with CM. Most of the ruminal parameters did not differ (p > 0.05) among dietary treatments. Therefore, Fator P® represents a viable and safe strategy for supplementation to beef cattle finished using high‐concentrate diet in feedlot systems.

Fatty acid profiles of muscle, liver, heart and kidney of Australian prime lambs fed different polyunsaturated fatty acids enriched pellets in a feedlot system

We investigated the effect of various dietary polyunsaturated fatty acid (PUFA) sources on the fatty acid profiles of muscle, liver, heart and kidney of Australian prime lambs. Seventy-two White Suffolk x Corriedale first-cross lambs weaned at 6 months of age were randomly allocated to the following six treatments: (1) Control: Lucerne hay only; wheat-based pellets infused with 50 ml/kg dry matter (DM) of oil from (2) rice bran (RBO); (3) canola (CO); (4) rumen-protected (RPO), (5) flaxseed (FSO) and (6) safflower (SO) sources in a completely randomized experimental design. Lambs in CO, FSO, SO and RPO treatments achieved contents of eicosapentaenoic acid (EPA, 22:5n-3) plus docosahexaenoic acid (DHA, 22:6n-3) in the longissimus dorsi muscle ranging from 31.1 to 57.1 mg/135 g, over and above the 30 mg per standard serve (135 g) threshold for “source” claim under the Australian guidelines. There was no difference in n-3 LC-PUFA contents in longissimus dorsi muscle of lambs fed dietary oils of plant origin. The highest 18:3n-3 (ALA) contents achieved with FSO diet in the muscle, liver and heart were 45.6, 128.1 and 51.3 mg/100 g, respectively. Liver and kidney contained high contents of n-3 LC-PUFA (ranging from 306.7 to 598.2 mg/100 g and 134.0 to 300.4 mg/100 g, respectively), with all values readily exceeding the ‘good source’ status (60 mg per serve under Australian guidelines). The liver and kidney of PUFA fed lambs can be labelled as ‘good source’ of n-3 LC-PUFA based on EPA and DHA contents stipulated by the Food Standards of Australia and New Zealand guidelines. Therefore, if lamb consumers consider eating the liver and kidney as their dietary protein sources, they can adequately obtain the associated health benefits of n-3 LC-PUFA.

Ewe and lamb pre-weaning performance of Pelibuey and Katahdin hair sheep breeds under humid tropical conditions

Pre-weaning is an important stage in sheep production systems focussed on meat production. In this stage, maternal ability has a key role in lamb development and productivity. The objective of this study was to evaluate the effect of breed and litter size at birth on the ewe and lamb pre-weaning performance under tropical conditions. The lambs and their dams were managed in a feedlot system during 56 days in individual pens. Milk production was estimated weekly by the weight-suck-weight method. Daily milk production (DMY), total milk production (TMY), body weight change during the lactation (BWC), litter weaning weight (LWW) and ewe weaning efficiency (EE) were estimated as ewe pre-weaning performance; and, birth weight, weaning weight at 56 days and average daily gain were estimated as lamb pre-weaning performance. Katahdin ewes produced more TMY than Pelibuey ewes (p < .001) but ewes from both breeds had similar overall LWW and EE. Pelibuey ewes had a more negative BWC than Kathadin ewes (p < .05). Katahdin lambs had greater birth weights (p < .05), but similar pre-weaning growth and live weight at weaning compared with Pelibuey lambs. Litter size effect was significant for all the traits except for BWC in both breeds. Compared to Katahdin twin-born lambs, Pelibuey twin-born lambs were lighter at birth but of similar weight at weaning. Litter size is an important factor conditioning pre-weaning performance of ewes and lambs of Pelibuey and Katahdin breeds under humid tropical conditions.HighlightsSome indicators of ewe and lamb pre-weaning performance of Pelibuey and Katahdin hair sheep under tropical conditions were evaluated.The Katahdin ewes produced more milk than Pelibuey ewes, yet ewes from both breeds had similar litter weaning weight.Litter size is an important factor determining pre-weaning performance in Pelibuey and Katahdin hair sheep breeds under humid tropical conditions.

Growth performance and carcass traits of steers finished on three different systems including legume–grass pasture and grain diets

Inclusion of legume in grass pastures optimizes protein values of the forage and promotes improved digestibility. Therefore, we hypothesized that finishing steers on a novel combination of legumes and grass pasture would produce carcasses with acceptable traits when compared to carcasses from steers finished in feedlot systems. In this study, we evaluated the effects of finishing steers on three systems including: grazing legume–grass pasture containing oats, ryegrass, white and red clover (PAST), grazing PAST plus supplementation with whole corn grain (14 g/kg BW (SUPP)), and on a feedlot-confined system with concentrate only (28 g/kg BW, consisting of 850 g/kg of whole corn grain and 150 g/kg of protein–mineral–vitamin supplement (GRAIN)) on growth performance of steers, carcass traits and digestive disorders. Eighteen steers were randomly assigned to one of three dietary treatments and finished for 91 days. Data regarding pasture and growth performance were collected during three different periods (0 to 28, 29 to 56 and 57 to 91 days). Subsequently, steers were harvested to evaluate carcass traits, presence of rumenitis, abomasitis and liver abscesses. The legume–grass pasture provided more than 19% dry matter of protein. In addition, pasture of paddocks where steers were assigned to SUPP and PAST treatments showed similar nutritional quality. When compared to PAST, finishing on SUPP increased total weight gain per hectare, stocking rate, daily and total weight gains. The increase of weight gain was high to GRAIN than SUPP and PAST. Steers finished on GRAIN had high hot carcass weight, fat thickness and marbling score when compared to PAST. However, these attributes did not differ between GRAIN and SUPP. Abomasum lesions were more prevalent in steers finished on GRAIN when compared to PAST. Results of this research showed that it is possible to produce carcasses with desirable market weight and fat thickness by finishing steers on legume–grass pasture containing oats, ryegrass, white and red clover. Moreover, supplementing steers with corn when grazing on legume–grass pasture produced similar carcass traits when compared to beef fed corn only.

Carcass characteristics and meat quality of Nellore bulls submitted to different nutritional strategies during cow–calf and stocker phase

There have been few studies realized that evaluate the effects of adoptingdifferent nutritional systems in more than one phase of cattle production oncarcass and meat characteristics. This study was realized to evaluate carcassand meat characteristics from bulls submitted to different nutritional systemsduring two production phases. The experiment was conducted atFigueira’s farm during two production phases: I (cow–calf)– 80 calves (99.6±2.72 days of age and109.7±2.99 kg of BW) with their mothers were randomly assigned intotwo supplemental diets: cow–calf mineral supplement(n=40) or cow–calf creep-feeding(n=40); II (stocker) – the same 80calves (201.2±2.11 days of age and 190.2±3.37 kg of BW)were redistributed into two production systems: stocker pasture(n=40) or stocker feedlot (SF;n=40). After, all 80 animals were kept on a pasturesystem (III) for 290 days, and then finished in a feedlot system (IV) for more33 days. Then, they were slaughtered at an average 764.2±3.06 days ofage and at 499.2±3.33 kg of final BW. After slaughter, the averagedaily gain was calculated, and the carcass and meat characteristics weremeasured. The statistical model design used was completely randomized in a2×2 factorial arrangement (two treatment groups oncow–calf phase and two treatment groups on stocker phase). The singleeffects between the groups in each phase and the interactions between bothphases (cow–calf v. stocker) were analyzed. Theresults were compared by Fisher’s test, using the R statisticalsoftware. A cow–calf by stocker phases interaction occurred forcarcass conformation and fiber diameter. For single effects, the greatestinfluences observed were in the stocker phase. The feedlot group was slaughtered17 days earlier, with greater final BW (3.8%), hot carcass weight(5.7%), average daily gain (6.9%), dressing percentage(1.8%), carcass length (1.8%), carcass width(1.5%), longissimus muscle area (4.8%)and muscle depth (2.3%) than pasture group. The SF group also hadinfluence on fat color; showing higher L* and lowerb* values. These results reveal that bullsreared in feedlot at the stocker phase have higher muscle development and thatthe stocker phase has the greatest potential to influence carcasscharacteristics and meat quality.

Roughage-free finishing diet based on whole corn grain and a mixture of additives for Nellore heifers

ABSTRACT This study was carried out to evaluate the effect of a blend of additives (choline, methionine, selenium, and organic zinc) on performance, feed efficiency, rumen parameters, and carcass traits of Nellore heifers finished with roughage-free diet. Nellore heifers (n = 36; average BW = 244±24.1 kg; average 24 months of age) were maintained in a feedlot system for 86 d. Heifers were separated into two groups: control and additive. Heifers in control group were fed a based diet composed of 850 g kg−1 corn grain and 150 g kg−1 of a mineral-vitamin-protein pellet. The additive group was fed a diet supplemented with a blend of choline, methionine, selenium, and organic zinc at 1,667, 4,000, 1, and 24.37 mg kg−1 of the diet dry matter, respectively. The animals were allotted to 18 pens (two heifers/pen), with nine pens per treatment. Heifers were weighed, blood samples were collected, ultrasonography examinations were performed periodically, and hot carcass and papillae samples were taken at slaughter. Data were analyzed as a completely randomized design. The model included the fixed effect of treatments (control and additive). Additive supplementation did not change dry matter intake, performance, or feed efficiency. There was no effect of additives on muscle or fat tissue deposition. Consequently, no changes in hot carcass weight and dressing were found. Overall, additive inclusion did not alter blood parameters, blood electrolyte balance, and rumen traits. Nellore heifers finished with roughage-free diets have no improvement on production traits nor in their rumen health by supplementation with a blend of choline, methionine, selenium, and organic zinc.

PSIX-29 Effect of condensed tannin extract (BYPRO®) on carcass traits of cattle in a feedlot system.

PSIX-29 Effect of condensed tannin extract (BYPRO®) on carcass traits of cattle in a feedlot system.

Nutritional Supplements Fortified with Oils from Canola, Flaxseed, Safflower and Rice Bran Improve Feedlot Performance and Carcass Characteristics of Australian Prime Lambs.

Simple SummaryThis study evaluated the feedlot response of Australian prime lambs to supplementation with oil based polyunsaturated fatty acid enriched pellets. The results demonstrated that live animal performance and carcass characteristics of prime lambs on a lucerne basal diet were improved after the supplementation with oil based polyunsaturated fatty acid enriched pellets. Supplementation of lambs with rice bran oil and canola oil resulted in improved live animal performance and carcass characteristics of prime lambs at comparatively lower feed costs than oils from flaxseed, safflower and rumen-protected sources. These results are very useful for prime lamb producers in increasing product quality and farm profitability without compromising animal performance and well-being.This study investigated live animal performance and carcass characteristics of Australian prime lambs fed oil based polyunsaturated fatty acid (PUFA) enriched pellets in a feedlot system. The tested hypothesis was that supplementation of lambs with a variety of dietary oil based PUFA enriched pellets would enhance growth and carcass characteristics compared with the control lambs fed only with lucerne hay. Seventy-two, 6 months old White Suffolk x Corriedale first-cross prime lambs with an average liveweight (LWT) of 35.7 ± 0.9 kg were allocated to six treatment groups in a completely randomised experimental design. The treatments were: (1) control: lucerne hay only; or lucerne hay plus wheat-based pellets infused with 50 mL/kg dry matter (DM) of oils from (2) rice bran (RBO); (3) canola (CO); (4) rumen protected (RPO); (5) flaxseed (FO) and (6) safflower (SO) dietary sources. All lambs had ad libitum access to lucerne hay and clean fresh water. Supplemented lambs were fed 1 kg of pellet/head/day for 10 weeks. Feed intake, final LWT, average daily gain (ADG), body conformation and carcass characteristics of lambs in the supplemented groups were all greater than for the control group. SO lambs had the lowest ADG of 190.3 g/day. RBO and CO treatments had the lowest feed cost per unit gain of AU$3.0/kg. Supplemented lambs had similar over the hooks (OTH) incomes that were all higher than that of the control group. This empirical evidence-based data demonstrated that supplementation of lambs with RBO and CO had comparatively lower feed costs without compromising ADG, carcass characteristics and OTH income.

Economic viability of finishing lambs in the feedlot using bovine cheese whey as a dietary ingredient

The aim of this study was to evaluate the economic viability of finishing Morada Nova in two feedlot systems: with and without inclusion of bovine cheese whey in the diet. Extrapolation was performed to a module of 240 lambs per year based on a three-cycle production system (each cycle with 100 days). The use of bovine cheese whey resulted in better economic viability. Reduction of labor costs and improvement of the lambs’ sale price at the end of the finishing phase were major factors.

Mitigating Greenhouse Gas and Ammonia Emissions from Beef Cattle Feedlot Production: A System Meta-Analysis.

Beef cattle production systems are the largest contributors of greenhouse gas (GHG) and ammonia (NH3) emissions in the livestock industry. Here, we present the first meta-analysis and integrated assessment of gaseous emissions and mitigation potentials for a typical beef cattle feedlot system, including methane (CH4), nitrous oxide (N2O), and NH3 losses from enteric fermentation and manure management based on data from 104 studies. A total of 14 integrated emission factors (EF) and the mitigation efficiencies (ME) of 17 available options were provided. The estimated GHG and NH3 emissions from the baseline feedlot system were 2786 ± 108 kg carbon dioxide equivalents (CO2-eq) per animal unit (AU) per year and 49.1 ± 1.5 kg NH3 AU-1 year-1, respectively. Enteric CH4 fermentation and manure on the feedlot contributed 67.5% and 80.8% of the total system GHG and NH3 emissions, respectively. The highest ME values were found for lipid additives for enteric CH4 fermentation and urease inhibitor additives (UI) for NH3 emissions from manure on the feedlot, being -14.9% ( p < 0.05) and -59.5% ( p < 0.001), respectively. The recommended mitigation combinations of a low-crude-protein (CP) diet and a UI additive for manure on the feedlot could reduce the GHG of the system by 4.9% and NH3 by 50.9%. The results of this study have important implications for developing sustainable beef cattle feedlot systems from the viewpoint of GHG and NH3 mitigation.

Rumen and liver measurements of lambs fed with high inclusions of crude glycerin in adaptation and finishing period of feedlot

Crude glycerin is the main by-product of biodiesel industry and has great potential for reducing the feed costs in ruminant feedlot systems without affecting animal health and performance, mainly as a replacement for corn grain. The objective of this study was to evaluate the effects of increasing inclusions of crude glycerin (up to 30%) in diets for crossbred feedlot lambs in two different periods (adaptation and finishing) on the rumen morphometric and liver variables. Fifty-five 3-month-old crossbred lambs were randomly allocated in individual pens indoors, assigned to a complete randomized block design and fed with four experimental diets, containing 0, 10, 20 or 30% crude glycerin. Three animals were slaughtered at the end of the pre-adaptation period (d0), twelve at the end of the adaptation period (d14), and the remaining (n = 40) when they reached approximately 35 kg BW. After slaughtered, the stomach compartments and liver were collected and evaluated. All stomach compartments, number of rumen papillae and mitotic index were higher for the finishing period (P < 0.05). Crude glycerin treatments showed greater rumen weights when compared to control treatment (G0 vs G, P = 0.01) in the finishing period. The increasing inclusion of up to 30% of crude glycerin/kg DM in diets for crossbred lambs did not compromise the stomach compartments and rumen papillae measurements in both periods of the feedlot. No clinical manifestations resulted from ruminal acidosis (such as liver abscess, ruminitis, and lesions in the ruminal mucosa) were observed in any period and treatment studied. Thus, we conclude that the replacement of corn cracked grain by crude glycerin (up to 30% DM) was effective in the animals’ adaptation to concentrate-based diets.