Ground Hay Research Articles

Application of near-infrared spectroscopy for hay evaluation at different degrees of sample preparation.

A study was conducted to quantify the performance differences of the nearinfrared spectroscopy (NIRS) calibration models developed with different degrees of hay sample preparations. A total of 227 imported alfalfa (Medicago sativa L.) and another 360 imported timothy (Phleum pratense L.) hay samples were used to develop calibration models for nutrient value parameters such as moisture, neutral detergent fiber, acid detergent fiber, crude protein, and in vitro dry matter digestibility. Spectral data of hay samples prepared by milling into 1-mm particle size or unground were separately regressed against the wet chemistry results of the abovementioned parameters. The performance of the developed NIRS calibration models was evaluated based on R2, standard error, and ratio percentage deviation (RPD). The models developed with ground hay were more robust and accurate than those with unground hay based on calibration model performance indexes such as R2 (coefficient of determination), standard error, and RPD. Although the R2 of calibration models was mainly greater than 0.90 across the feed value indexes, the R2 of cross-validations was much lower. The R2 of cross-validation varies depending on feed value indexes, which ranged from 0.61 to 0.81 in alfalfa, and from 0.62 to 0.95 in timothy. Estimation of feed values in imported hay can be achievable by the calibrated NIRS. However, the NIRS calibration models must be improved by including a broader range of imported hay samples in the modeling. Although the analysis accuracy of NIRS was substantially higher when calibration models were developed with ground samples, less sample preparation will be more advantageous for achieving rapid delivery of hay sample analysis results. Therefore, further research warrants investigating the level of sample preparations compromising analysis accuracy by NIRS.

PSI-17 Use of Sunn Hemp as Forage for Early-Weaned Beef Calves

Abstract Sunn hemp (Crotalaria juncea) has been widely used as cover crop in the USA and due to superior biomass accumulation and nutritive value, there is interest from producers to use sunn hemp as forage for livestock. However, sunn hemp has pyrrolizidine alkaloids, which can affect animal performance. The objective of this study was to evaluate the effects of feeding sunn hemp hay to early-weaned beef calves in a dry lot in Florida. The experiment was conducted at the UF/IFAS Range Cattle Research and Education Center, Ona, FL from April to May 2021 (42 d). Treatments were calves receiving sunn hemp or stargrass (Cynodon nlemfuensis) hay distributed in a randomized complete block design with 12 replicates. Calves were supplemented with concentrate at 1.3% BW daily (18% CP and 78% TDN). Twenty-four Angus crossbred calves were weaned with 90 ± 14 kg BW and grazed annual ryegrass (Lolium multiflorum) with 1% BW concentrate supplementation for approximately 60 d. Subsequently, calves were randomly distributed and assigned to experimental units (pen) on 14 April 2021 with initial BW of 184 ± 10 kg. ‘Ubon’ sunn hemp hay was harvested approximately 49 d after seeding when 75% of the plants were initially flowering. Ground hay was fed daily targeting 10% refusals, and the initial CP and in vitro digestible organic matter concentrations of sunn hemp and stargrass hay were 9 and 48%, and 9 and 47%, respectively. The average concentration of pyrrolizidine alkaloids from sunn hemp hay was 58 μg/g DM. Early-weaned calves receiving stargrass had a tendency to have greater ADG than sunn hemp (0.5 vs. 0.4 kg/d, P = 0.09), and had greater forage DM intake (1.2 vs. 1.0% BW, P < 0.01) and total DM intake (2.5 vs. 2.3% BW, P < 0.01). Conversely, diets with sunn hemp had greater in vivo DM digestibility than stargrass (68 vs. 62%, P = 0.04). There was no difference between treatments on parasite egg count (mean = 45 eggs/3 g feces, P = 0.25) and coccidia egg count (log10 eggs/g feces, P = 0.35). Early-weaned calves receiving sunn hemp consumed 0.25 g pyrrolizidine alkaloids/d; however, there was no detectable amount (< 0.05 μg/g DM) of pyrrolizidine alkaloids in the feces. The presence of pyrrolizidine alkaloids in sunn hemp may be the potential cause of decreased early-weaned calves forage intake and animal performance.

PSI-25 Associations Between Feeding Behavior, Residual Feed Intake, and Residual Average Daily Gain in Performance Tested Yearling Angus Bulls and Heifers

Abstract The objective of this study was to evaluate relationships among feeding behaviors, off-test residual feed intake (RFI), and residual average daily gain (RADG) EPD for performance tested cattle. Eighty-seven angus bulls and thirty-two angus heifers (n = 119) were fed a high forage diet consisting mainly of ground hay and corn silage for 57 days using the Vytelle feed system. The variables evaluated were time spent visiting the bunk, time with head down, number of visits, RFI, average DMI, DMI, RADG, ADG, and quadrant location of RFI and ADG. RFI and ADG are plotted for each individual animal, which places that individual into one of four quadrants (1 = Favorable RFI/ Below average ADG, 2 = Favorable RFI/ Above average ADG, 3 = Unfavorable RFI/ Below average ADG, 4 = Unfavorable RFI/ Above average ADG). The data were analyzed by gender, using non-parametric Spearman’s Rho in JMP to determine variable relationships. A very strong positive correlation was observed in yearling bulls for the time spent with head down and the length of time spent at the bunk (0.8331, P < 0.0001). Also, a moderate correlation for the animals individual RFI and total number of visits (0.4924, P < 0.0001). A very strong negative correlation was observed for yearling bulls in the average amount consumed and the total number of visits to the bunk (-0.8380, P < 0.0001). Also, a weak negative correlation was observed in the animals individual RADG and RFI (-0.2777, P < 0.0001). Similarly, a strong positive correlation in yearling heifers was observed in head down and length of time spent at the bunk (0.9457, P < 0.0001). A strong negative correlation was observed in yearling heifers for the total number of visits and the average amount of feed consumed per each visit (-0.5293, P < 0.0018). Also, a moderate negative correlation in each animals individual RADG and RFI (-0.4822, 0.0052*). While a moderate positive correlation of individual animal RFI and the total number of visits was observed for the yearling bulls, the yearling heifers showed no significant correlation between the two. Our studies show that feeding behavior on a high forage diet is similar to that of behaviors shown on a high concentrate diet by others. Although there was a significant, but weak relationship between RFI and RADG, the strength of the relationship is such that one cannot be used predict the other and they are measuring different components of the animal’s efficiency.

PSI-A-8 The Effect of Rumen Capacity Manipulation on Dry Matter Intake on Diets Differing for Processing Level

Abstract Rumen fill is a driving force behind intake in ruminant animals consuming unprocessed forage. The objective of this study was to determine the effect of rumen available capacity on feed intake of diets processed to different levels. To evaluate the effect of rumen capacity, intake of a fistulated Angus heifer (716 kg, 4 yr) was evaluated at full rumen capacity and one-half capacity on the same diet processed to three different fiber lengths: unprocessed, long-stemmed hay, processed in a bale buster to fiber lengths of 15 cm, and ground hay with fiber lengths of 3 cm. The heifer was housed in a drylot pen with ad libitum access to water and consumed the diet out of a SmartFeed individual intake unit. The intake unit was filled twice a day at 0700 and 1700 h. The heifer consumed each diet for a period of 10 days. The first 5 days of each period the heifer consumed the diet at full rumen capacity, for the remaining 5 days of each period, two weather balloons were inserted into the rumen and distended with water to reduce rumen capacity to 50% capacity. As expected, the heifer consumed more of the diet when the diet had some form of further processing (P < 0.05). Rumen capacity affected intake in a linear manner related to the level of processing in the diet (P < 0.05).

Ex Vivo Fermentation of Hay and Corn by Rumen Bacteria from Cattle and Sheep

Sheep are often utilized as a model ruminant, despite a lack of functional comparisons of rumen bacterial communities and responses during dietary transitions between sheep and cattle. Therefore, an ex vivo study was conducted to evaluate species differences. Rumen fluid was obtained from hay-fed sheep and cattle (n = 3 species−1). Mixed bacterial cell suspensions in buffered media containing 3% w/v ground hay, corn, or combinations (2:1, 1:2) of substrates were incubated (24 h; 39 °C). Suspension pH, lactate, volatile fatty acids (VFA), and digestibility were assessed, functional guilds enumerated, and amylolytic bacteria isolated. Lactate was fully utilized in all hay incubations, and pH did not differ between species (p > 0.75). In contrast, digestibility, lactate accumulation, and pH decline were greater in bovine suspensions fermenting corn (p < 0.01). Streptococcus bovis was the predominant bacteria regardless of species, but total amylolytic bacteria were 10-fold greater in bovine suspensions (p < 0.01). Lactate-utilizing bacteria were 1000-fold greater in bovine than ovine suspensions (p < 0.01). However, total VFA did not differ between species (p > 0.28). Overall, these results demonstrate differential feed utilization capacities in rumen microbial communities of sheep and cattle as well as potential differences in rumen acidosis susceptibility.

Dietary alfalfa hay or lipid-soluble alfalfa extract may improve broiler growth, but fiber presence may be detrimental during Eimeria vaccine challenge

Lipid-soluble components in late-cutting alfalfa are linked to beneficial immune and microbiota responses in mouse challenge models; therefore, responses in a comparative poultry Eimeria challenge model were investigated. The study objective was to evaluate performance, immunity, and the cecal microbiota in broilers fed ground hay or lipid-soluble extract from late (fifth) cutting alfalfa during Eimeria challenge. At hatch, 432 Ross 708 broilers were placed in 24 floor pens (18 birds/pen) and assigned to 3 isocaloric/isonitrogenous dietary treatments consisting of control, 5% ground hay, or 0.25% lipid-soluble extract for a 42-d trial divided into 14 d starter, grower, and finisher periods. On d 14, 4 birds/treatment were euthanized to collect blood and cecal contents before half the remainder were inoculated with 10X Merck Coccivac-B52 (Kenilworth, NJ). Tissue samples were collected at 3, 7, 14, and 28 d postinoculation (pi; 4 birds/diet×Eimeria group) with body weight (BW) and feed intake (FI) recorded weekly. Immune populations within peripheral blood mononuclear cells were characterized by flow cytometry while cecal microbial communities were profiled by 16S rRNA gene amplicon sequencing. Data were normalized when appropriate and analyzed to evaluate the effects of diet, Eimeria challenge, and timepoint (SAS 9.4; P ≤ 0.05). Before challenge, dietary alfalfa hay or extract increased FI 6.9 to 8.0% and increased CD3+ T cells 19.3 to 24.9% compared to control-fed birds (P ≤ 0.007). Alfalfa did not significantly affect post-Eimeria performance, but Eimeria-challenged birds fed hay showed the greatest numeric reduction in final BW compared to their unchallenged counterparts (0.17 kg) vs. control and extract-fed birds (0.02-0.04 kg). Immune cell changes did not indicate recruitment from peripheral blood to local infection sites; however, alfalfa hay may have accelerated Bu-1+ B cell development by 7 d in unchallenged birds (P < 0.0001). During Eimeria-challenge, dietary alfalfa extract preserved alpha diversity measures related to species richness (P ≤ 0.007). Collectively, these results indicate potential benefits of feeding lipid-soluble extract from late cutting alfalfa to broilers during Eimeria challenge.

PSVI-13 Nutritional Supplementation with Leftover Food of Dairy Cows Upon Reproductive Response of Goats

Abstract To evaluate the effect of nutritional supplementation with leftover food of dairy cows upon the reproductive response of multiracial female goats fed in open range in northern Mexico (26°N, 104°W), 38 multiparous goats in extensive grazing conditions were randomly assigned to two groups with similar weight (BW; Kg) and body condition score (BCS; scale 1-5). The control group (CG; n=19; BCS 1.7± 0.03; BW 60.42 ± 1.5 Kg, fed only in native vegetation) and supplemented group (SG; n=19; BCS; 1.7± 0.07; BW 60.21± 0.97 Kg) were fed native vegetation plus a nutritional supplementation with a ration fully mixed of leftover dairy feed, which consisted of 96.67 g of corn silage, 54.08 g of alfalfa ground hay, 49.38 of soybean paste, 37.80 g of cottonseed, 124.27 g of rolled corn and 37.80 g of commercial mixture with vitamins and minerals (totaling 400g; 14.5 PC,80% DM). The diet was offered individually daily (before grazing) from day -5 to +15 of the study. All females were subject to the male effect (Day 0; 2/group) for 10 days. By transrectal ultrasonography (Aloka SSD-500; 7.5MHz) were determined: the proportions of females having ovulations (OF: day 8) and pregnant females (PF, day 45). All data were compared using a Chi-square test (IBM SPSS 25). Differences were observed (P&amp;lt; 0.05) for OF (SG:15/19;78.9% vs CG: 9/19; 47.3%), but not for PF (SG:10/19; 52.6% vs CG: 6/19; 31.5%). We conclude that the proportion of ovulating females was greater n SG than in CG, nevertheless, the PF was not different, possibly because the time in which the nutritional supplementation was offered did not influence the period of embryonic implantation, it would be interesting to do an experiment extending the period of nutritional supplement with leftover food.

Effects of Dietary Inclusion of Sericea Lespedeza Hay on Behavior, Heat Energy, and Ruminal Methane Emission by Growing Alpine Doelings and Katahdin Ewe Lambs

Abstract Twenty-four Alpine doelings (initial body weight (BW) and age of 25.3±0.55 kg and 10.4±0.11 mo, respectively) and 24 Katahdin ewe lambs (28.3±1.02 kg and 9.6±0.04 mo, respectively) were used to determine effects of dietary level of Sericea lespedeza (Lespedeza cuneata; 10% condensed tannins) on heat energy and ruminal emission of the greenhouse gas methane determined with an open-circuit calorimetry system. Pens with Calan feeding gates were used in the study with four 6–7-wk periods. Diets (i.e., treatments) consumed ad libitum were 75% ground hay, alfalfa, a 1:1 mixture of alfalfa and lespedeza (AL), and lespedeza. Data were analyzed with a 2 x 3 factorial arrangement of treatments, repeated measure of period, and a mixed effects model. Feeders were open 195 and 205 min/d for Alpine and Katahdin (SEM=9.8) and longer (P &amp;lt; 0.05) for diets with lespedeza (159, 209, and 231 min/d for alfalfa, AL, and lespedeza, respectively). Rate of dry matter intake (DMI) was greater (P &amp;lt; 0.05) for Katahdin vs. Alpine (10.2 and 6.1 g/min) and for alfalfa than for AL and lespedeza (11.1, 8.1, and 6.7 g/min, respectively). Heat energy was greater (P &amp;lt; 0.05) in MJ/d for Katahdin than for Alpine (10.19 vs. 7.90) and similar among diets (9.20, 9.40, and 8.53; SEM=0.266), but values in kJ/kg BW0.75 were similar between animal types (560 and 579; SEM=8.4) and greatest (P &amp;lt; 0.05) among diets for AL (563, 592, and 553 for alfalfa, AL, and lespedeza, respectively). Ruminal methane emission differed (P &amp;lt; 0.05) between animal types in MJ/d (1.17 and 1.44), kJ/g DMI (1.39 and 1.23), and kJ/g average daily gain (ADG; 18.1 and 9.8 for Alpine and Katahdin, respectively). Regardless of period, diet did not impact methane emission in MJ/d or relative to DMI, BW, or ADG. In conclusion, it is unclear why dietary inclusion of lespedeza did not reduce ruminal methane emission as in previous studies. Species differences in methane relative to DMI and ADG (i.e., lower for sheep than for goats) deserve further attention.

PSI-7 Differing planes of nutrition affecting the cytokines of bovine seminal plasma in beef cattle

Abstract Bull fertility is highly influential to profits of cow-calf production; however, bulls often experience various planes of nutrition throughout the year. These changes may influence the composition of the ejaculate and their ability to get females pregnant. We hypothesized that differing nutritional planes would affect the cytokines concentration in the seminal plasma of bulls. Mature angus bulls (n = 12) were individually housed and randomly assigned to one of two treatments: 1) over-fed (n = 6) or 2) restricted (n = 6). Bulls were fed the same ration (35% ground hay, 35% cracked corn, 20% distillers’ grain and 10% soybean meal) at differing volumes to achieve desired nutritional planes. Body weight and BCS were taken every two weeks to monitor nutritional planes. Blood and ejaculate were collected once a month to determine cytokine profiles within seminal plasma. Statistical analyses were conducted with GLIMMIX procedure of SAS with bull within treatment as a random effect and time as a repeated measure to determine if nutrition level, time and the interaction influenced seminal plasma cytokine concentration. There were no significant time or treatment×time interactions for any cytokine concentrations. Interferon-γ tended to be increased (P &amp;lt; 0.10) in restricted bulls (3.21±0.95 pg/mL) compared with over-fed bulls (0.64±0.95 pg/mL). The concentrations of IL-8 also tended to be increased (P &amp;lt; 0.10) in restricted (318.89±66.42 pg/mL) compared with over-fed bulls (158.02±66.42 pg/mL). Interleukin-1β in over-fed bulls (24.77±17.51 pg/mL) tended to be decreased (P &amp;lt; 0.10) compared with restricted bulls (65.8±17.51 pg/mL). Interleukin-10 tended to be greater (P &amp;lt; 0.10) in restricted (17.95±2.29 pg/mL) than in the over-fed bulls (12.41±2.29 pg/mL). The concentration of VEGF-A was greater (P &amp;lt; 0.05) in restricted bulls (3,551.28±224.49 pg/mL) than over-fed bulls (2,715.72±224.49 pg/mL). In conclusion, cytokine concentrations were elevated by restricted nutritional levels which could impact the ability of the ejaculate to stimulate uterine gene expression and establish pregnancy.

PSXII-31 Severity of hay processing on dry matter intake, sorting behaviour, and apparent total tract digestibility in lambs

Abstract The objective was to evaluate digestibility and sorting behaviour of grass hay processed to differing severities. Thirty-six wether lambs were used in a completely randomized design and fed diets consisting of grass hay (82.2 %), whole barley (15.7 %), and a mineral-vitamin supplement (2.1 %). Treatments included: unprocessed hay (CON); shredded hay (SHRED); chopped hay (CHOP); and ground hay (GRIND). Lambs were fed their respective diet for 20 d followed by 4 d for measurement of feed intake and fecal output. Lambs fed CON (1.23 kg and 3.24 %) had greater DMI (P = 0.04 and 0.05) compared to CHOP (1.04 kg and 2.71 % BW), with SHRED (1.17 kg and 3.11 % BW) and GRIND (1.13 kg and 2.97 % BW) being intermediate. Undigestible NDF intake tended to decrease as processing severity increased (P = 0.05). Dry matter digestibility (67.6, 66.2, 59.6, and 60.8 % for CON, SHRED, CHOP, and GRIND, respectively; P &amp;lt; 0.01) generally decreased as the severity of forage processing increased. Crude protein digestibility was greatest in CON (68.6 %) compared to SHRED (60.83 %), CHOP (58.7 %), and GRIND (58.5 %; P &amp;lt; 0.01). ADF and aNDFom digestibilities were greater for CON (57.4 and 67.2 %) and SHRED (60.0 and 67.9 %) compared to CHOP (44.8 and 54.6 %) and GRIND (48.3 and 58.5 %; P &amp;lt; 0.001). CON and SHRED lambs sorted for larger particle sizes (particles &amp;gt; 19 mm and 8 to 19 mm; P &amp;lt; 0.001 and 0.025, respectively) while CHOP and GRIND lambs sorted for smaller particles (particles 4 to 8 mm and particles &amp;lt; 4 mm; P &amp;lt; 0.001 and 0.003, respectively). These results indicate that processing of grass hay does not increase nutrient digestibility partly because of the sorting behaviour of lambs.

77 Responses to alfalfa supplementation in mice

Abstract Anecdotal evidence suggests health benefits from feeding late cutting alfalfa to non-ruminants, but there is a lack of published literature to support these claims. The objective was to compare early (1st) and late (5th) cutting alfalfa as ground hay, aqueous, or chloroform-extracted hay in combination with a gastrointestinal challenge to understand the effect of supplementation form and cutting on the overall health, microbiome, and immune system of mice. 163 C57BL/6J mice were housed for 35 d (Innovive system; 2–4 mice/cage) and fed treatments that consisted of an 18% protein rodent diet (alfalfa-free control), or control supplemented with 1st or 5th cutting 9% ground alfalfa hay, 0.25% aqueous extract (AAE), or 0.25% chloroform extract (CAE). After a 14 d enrichment period, 6 mice/treatment were euthanized for baseline tissue and digesta sampling, and remaining mice were orally gavaged with 2x1010 CFU Citrobacter rodentium. On d18, 22, 28, and 35, 4 mice/treatment were euthanized for sampling. Body weight (BW) and feed intake (FI) were recorded, 13 serum cytokines were measured, and changes in the microbial communities were analyzed using 16S rRNA amplicon sequencing. Data were analyzed using PROC MIXED and linear discrimination analysis effect size (LEfSe), with significance at P ≤ 0.05. No BW differences were observed between treatments at the key timepoints (P &gt; 0.05). Mice fed hay diets ate 16% more per day during the enrichment period (P = 0.03), 19% more from d14–18 (P = 0.001), and 17% more from d18–22 (P = 0.03) versus mice fed AAE. Citrobacter rodentium infection was confirmed via MiSeq in colon digesta. Significant shifts in microbial taxa were observed in mice fed alfalfa hay regardless of cutting (P &lt; 0.05). Cytokine analysis, flow cytometry, and microbiome analysis is ongoing. Preliminary results show that alfalfa form significantly impacts FI and microbiome while cutting impacts weight (P &lt; 0.05).

Effects of feeding juniper as a roughage on feedlot performance, carcass measurements, meat sensory attributes, and volatile aroma compounds of yearling Rambouillet wethers1,2.

The majority of U.S. lambs are born during late winter or early spring, which can create downstream variability in carcass quality if commercial lamb harvest is to be relatively constant throughout the year. Flavor is an important quality determining characteristic of sheep meat and is influenced, in part, by animal age at harvest. However, management practices to mitigate the risk of objectionable flavors in meat from old crop lambs or yearlings are not well known. Yearling (16.8 ± 0.14 mo) Rambouillet wethers were assigned to 1 of 3 treatment groups, which consisted of feeding a 20% ground sorghum-sudangrass hay diet for 40 d (JUN0; n = 10), a 20% ground juniper diet for 40 d (JUN40; n = 10), or a 20% ground hay diet for 20 d followed by a 20% ground juniper diet for 20 d (JUN20; n = 10). Wethers were harvested on day 41 and a whole bone-in loin and a boneless inside leg roast were fabricated from one side each of carcass. After grilling (loin chop) or convection air roasting (leg roast), trained sensory panel evaluation and measurement of aroma volatiles by gas chromatography/mass spectrometry were performed. Treatment diet did not affect (P ≥ 0.17) wether feedlot performance, dressing percentage, or loin eye area. However, wethers fed JUN0 tended (P = 0.06) to have greater back fat depth than wethers fed JUN20 or JUN40. No trained sensory panel trait of loin chop samples was affected (P > 0.10) by treatment. Leg roasts from JUN0 and JUN20 wethers had greater (P = 0.01) lamb identification sensory score than JUN40. Benzaldehyde, 1-heptanol, and 1-octanol concentrations were greater (P < 0.05) and decanal and nonenal concentrations were less (P < 0.05) in loin chops from JUN0 compared with JUN40 wethers. Additionally, the terpenes cedr-8-ene, gamma muurolene, and widdrene tended to be greater (P < 0.07) in loin chops from JUN20 and JUN40 than JUN0 wethers. The 2-pentyl-furan concentrations were greatest (P = 0.03) in leg roasts from JUN40 wethers. Like the loin chops, cedr-8-ene, gamma-muurolene, toluene, and widdrene were greater (P < 0.05) in leg roasts from wethers fed either of the juniper diets compared with JUN0. Yearling wethers can be finished on a feedlot diet containing 20% juniper for up to 40 d prior to harvest with no impact on feedlot performance, carcass characteristics, nor negative impact on sensory attributes or volatile compounds of either grilled loin chops or roasted legs.

Current challenges in the diagnosis of zearalenone toxicosis as illustrated by a field case of hyperestrogenism in suckling piglets

BackgroundThe mycotoxin zearalenone (ZEN) causes functional and morphological alterations in reproductive organs of pigs. In the field, diagnosis of ZEN-induced disorders is often challenging, as relevant feed lots are no longer available, or feed analysis results are not conclusive. Here, we report a field case of hyperestrogenism in newborn piglets. Surprisingly, more than 50 fungal metabolites were detected in hay pellets fed to gestating sows, including ZEN and its modified form zearalenone-14-sulfate (ZEN-14-S). Despite the broad contamination range in this unconventional feed component, a definite diagnosis of mycotoxicosis could not be achieved. In this context, current limitations regarding the confirmation of suspected cases of ZEN-induced disorders are discussed, covering both feed analysis and the biomarker approach.Case presentationA piglet producer with 200 sows experienced a sudden increase in suckling piglet losses up to 30% by lower vitality and crushing. Predominant clinical signs were splay legs and signs of hyperestrogenism such as swollen and reddened vulvae in newborn piglets. The first differential diagnosis was ZEN mycotoxicosis although feed batches had not been changed for months with the exception of ground hay pellets, which had been included in the diet five months before. Analysis of hay pellets resulted in a sum value of ZEN and its modified forms of more than 1000 μg/kg, with ZEN-14-S alone accounting for 530 μg/kg. Considering the inclusion rate of 7% in the diet for gestating sows, the severe impact of the additional ZEN load due to the contaminated hay pellets seemed unrealistic but could not be completely excluded either. One month after hay pellets had been removed from the diet no further clinical signs were observed.ConclusionsEnrichment materials and other fibre sources can contain significant amounts of mycotoxins and should be therefore included in feed analysis. Adequate methods for broad spectrum mycotoxin determination, including modified mycotoxins, are important. As highlighted by this field case, there is a need to establish reliable biomarkers for ZEN exposure in pigs. Currently, available biomarkers do not allow a solid prediction of the ZEN intake of pigs under field conditions, which limits their application to experimental studies.

Changes in Rumen Microbial Profiles and Subcutaneous Fat Composition When Feeding Extruded Flaxseed Mixed With or Before Hay.

Extruded flaxseed (25%) and ground hay (75%) were each fed (DM basis) either together in a total mixed ration (TMR) or as flaxseed first followed by hay (non-TMR) to three pens of eight crossbred steers (n = 24 per diet) for 240 days. Compared to TMR, feeding non-TMR enriched subcutaneous fat with α-linolenic acid (ALA, 18:3n-3) and its biohydrogenation intermediates including vaccenic acid [trans(t)11-18:1], rumenic acid [cis(c)9,t11-conjugated linoleic acid] and conjugated linolenic acid (CLnA). Rumen microbial analysis using QIIME indicated that 14 genera differed (P ≤ 0.05) between TMR and the non-TMR. Azoarcus and Streptococcus were the only genera which increased in relative abundance in the TMR fed steers, whereas Methanimicrococcus, Moryella, Prevotella, Succiniclasticum, Succinivibrio, Suttenella, and TG5 decreased as compared to steers fed the non-TMR. Among these, Moryella, Succiniclasticum, and Succinivibrio, spp. were correlated with fatty acid profiles, specifically intermediates believed to be components of the major biohydrogenation pathway for ALA (i.e., t11, c15-18:2, c9, t11, c15-18:3, and total CLnA). In addition, negative correlations were found between the less abundant Ruminoccocus-like OTU60 and major ALA biohydrogenation intermediates, as well as positive correlations with several intermediates from alternative pathways that did not involve the formation of trans 11 double bonds. The present results suggest a number of pathways for ALA biohydrogenation are operating concurrently in the rumen, with their balance being influenced by diet and driven by less abundant species rather than members of the core bacterial population.

Biochanin A improves fibre fermentation by cellulolytic bacteria.

The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen cellulolytic bacteria and consequent fermentative activity. When bovine microbial rumen cell suspensions (n=3) were incubated (24h, 39°C) with ground hay, cellulolytic bacteria proliferated, short-chain fatty acids were produced and pH declined. BCA (30μgml-1 ) had no effect on the number of cellulolytic bacteria or pH, but increased acetate, propionate and total SCFA production. Addition of BCA improved total digestibility when cell suspensions (n=3) were incubated (48h, 39°C) with ground hay, Avicel, or filter paper. Fibrobacter succinogenes S85, Ruminococcus flavefaciens 8 and Ruminococcus albus 8 were directly inhibited by BCA. Synergistic antimicrobial activity was observed with BCA and heat killed cultures of cellulolytic bacteria, but the effects were species dependent. These results indicate that BCA improves fibre degradation by influencing cellulolytic bacteria competition and guild composition. BCA could serve as a feed additive to improve cellulosis when cattle are consuming high-fibre diets. Future research is needed to evaluate the effect of BCA on fibre degradation and utilization invivo.

Feeding steers hay with extruded flaxseed together or sequentially has a profound effect on erythrocyte trans 11-18:1 (vaccenic acid)

Extruded flaxseed and ground hay [25% and 75%; dry matter (DM) basis] were fed in a total mixed ration (TMR) or sequentially (non-TMR) to three pens of eight crossbred steers per diet. At 112 d, erythrocytes from non-TMR steers had 65% more vaccenic acid (trans 11-18:1) than TMR steers (P &lt; 0.05).

Influence of prepartum dietary energy on beef cow performance and calf growth and carcass characteristics

Objectives were to evaluate the effects of prepartum dietary energy intake on cow performance as well as performance and carcass characteristics of subsequent progeny. Spring-calving, mature cows (n=106 total) were blocked by BW and allotted to 1 of 2 treatments: ground hay and dried distillers grains plus solubles (REQ: TDN=61.8%, CP=11.0%, fat=2.1%), or corn bran and ground cornstalks (HE: TDN=70.3%, CP=10.0%, fat=5.7%). Treatments were limit-fed as isonitrogenous rations with REQ and HE providing 100% and 125% of TDN requirements, respectively, and were fed from 83±10d prepartum to calving. All cows were fed a common diet postpartum. Cow BW and BCS were recorded at the beginning of the feeding period, 24h post-calving, and at breeding. Milk production was estimated via the weigh–suckle–weigh technique 65±9 and 120±9d postpartum. Calf BW was measured at birth and at weaning (120±9d of age). Calves (n=86) were fed a common feedlot diet beginning 2d after weaning, and individual feed intake was monitored using GrowSafe. Progeny were slaughtered in 3 groups at an average 12th rib fat thickness of 1.3cm. From initiation of experiment to breeding, cow BW change was greater (P<0.01) and BCS change tended to be greater (P=0.09) for HE relative to REQ cows. Birth BW was greater (P=0.02) for calves born to cows fed HE with no increase (P=0.30) in percentage of unassisted births. There were no effects (P≥0.27) of treatment on calving date, milk production, or subsequent pregnancy rate. Calf weaning BW, initial feedlot BW, final BW, and days on feed were not affected (P≥0.20) by treatment. Feedlot DMI, ADG, and G:F were not different (P≥0.35). There was no effect (P≥0.27) of treatment on progeny morbidity. Although progeny born to HE dams tended (P=0.10) to have greater marbling scores at weaning, there was no effect (P≥0.60) of treatment on carcass marbling score or other carcass traits. Feeding cows 125% of TDN requirement during late gestation increased cow BW change and progeny birth body weight. Feeding cows 125% of TDN requirement during late gestation had no effect on pregnancy rate or progeny performance.

Alterações ultrassonográficas renais e vesicais de ovinos confinados e suplementados com cloreto de amônio

Resumo: A incidência da urolitíase obstrutiva em ovinos é elevada, principalmente em machos confinados, tanto para produção de carne, quanto reprodutores de alto valor genético. A acidificação urinária é um dos métodos para prevenção desta enfermidade e pode ser realizada de forma eficaz com a suplementação de cloreto de amônio (CA) na dieta. Utilizaram-se 100 ovinos, machos não castrados, mestiços (Ile de France X White Dorper), confinados, com idade aproximada de três meses. Constituíram-se três grupos experimentais: Grupo 21CA (n=40) que recebeu 400mg/kg/PV de cloreto de amônio/animal/dia, por 21 dias consecutivos; Grupo 42CA (n=40) que foi suplementado com 400mg/kg/PV de cloreto de amônio/animal/dia, por 42 dias consecutivos; Grupo controle (n=20), que não recebeu CA. A alimentação consistiu de ração total, composta por 15% de feno triturado e 85% de concentrado, água e sal mineral ad libitum. Após 14 dias de adaptação à alimentação e ao ambiente, os Momentos (M) de avaliação clínica, colheita de sangue e exame ultrassonográfico foram realizados com intervalo de sete dias, sendo M0 (imediatamente antes do início do tratamento com cloreto de amônio), M1 (sete dias após), M2 (14 dias após), M3 (21 dias após o início do tratamento e suspensão do cloreto de amônio em Grupo 21CA), M4 (28 dias após), M5 (35 dias após) e M6 (42 dias após), totalizando 56 dias de confinamento. As dosagens de ureia e creatinina não evidenciaram alteração na função renal, embora a ureia estivesse acima dos valores de referência para espécie ovina. Observaram-se imagens ultrassonográficas compatíveis com cálculos vesicais e dilatação de pelve renal. No Grupo 21CA, 15% (6/40) dos animais apresentaram cálculos vesicais; no Grupo 42CA, 5% (2/40); e no Grupo controle, 20% (4/20) dos cordeiros. Visibilizaram-se também imagens sugestivas de sedimentos e cristais em 31% (31/100) dos animais examinados. A ultrassonografia permitiu a visibilização de alterações renais e vesicais, porém não relacionados ao quadro clínico de urolitíase obstrutiva, revelando-se como um exame complementar de grande relevância para o diagnóstico precoce de alterações no sistema urinário de ovinos.

Passage kinetics of digesta in horses fed with coastcross hay ground to different degrees

This study was conducted to evaluate the kinetics, physicochemical characteristics and particle size of digesta in the right ventral colon (RVC) of horses fed coastcross hay ground to different degrees. Four horses fitted with cannulae in the RVC were used and were fed the following forms of hay: long, chopped, ground to 5 mm and ground to 3 mm. A Latin Square 4x4 study design was used. Each experimental period included 10 days for diet adaptation, four days for feces collection and one day for digesta collection. The kinetics of the particulate and solute phases of digesta were evaluated based on the mean retention time (MRT), passage rate (k) and transit time (TT) using two external markers: Cr-NDF and Co-EDTA. The TT of solid phase digesta was 3 hours longer (P&lt;0.05) for ground hay than with the other physical forms of hay. There was no difference (P&gt;0.05) in k or MRT in either the liquid or solid phase of digesta as a function of the different degrees of hay grinding. However, the liquid phase of digesta presented a higher k than the solid phase, with values of 3.28 and 2.73 h-1 being obtained, respectively. The smallest particle size and the lowest neutral detergent fiber contents in colon digesta were observed when hay ground to 3 mm was offered, leading to values of 0.51 mm and 53.46%, respectively. Grinding the hay increased the transit time of the liquid phase in the digestive tract of the horses, whereas no change in the kinetics of the solid phase digesta was observed. The grinding of hay reduced the NDF and the average particle size in the right ventral colon.

Efeito da suplementação de cloreto de amônio sobre os equilíbrios eletrolítico e ácido-básico e o pH urinário de ovinos confinados

A incidência da urolitíase obstrutiva em ovinos é elevada, principalmente em machos confinados, tanto para produção de carne, quanto reprodutores de alto valor genético. A acidificação urinária é um dos métodos para prevenção desta enfermidade e pode ser realizada de forma eficaz com a suplementação de cloreto de amônio na dieta, que pode propiciar a instalação de acidose metabólica. A hemogasometria avalia o equilíbrio ácido-básico sanguíneo de forma prática e fácil. Neste trabalho, avaliou-se o efeito do cloreto de amônio sobre o equilíbrio ácido-básico e eletrolítico de ovinos em confinamento para quantificar a acidose metabólica desenvolvida. Utilizaram-se 100 ovinos, machos, confinados, com idade aproximada de três meses. Constituíram-se três grupos experimentais: Grupo I (n=40), recebeu 400mg/kg/PV de cloreto de amônio/animal/dia por 21 dias consecutivos, momento da interrupção da administração do acidificante urinário (M3) e continuidade do acompanhamento clinico até o final do experimento (M6); Grupo II (n=40), 400mg/kg/PV de cloreto de amônio/animal/dia por 42 dias consecutivos; Grupo III (n=20), não recebeu cloreto de amônio durante todo o período do experimento. Os Momentos (M) de colheita de amostras e avaliação clínica foram estabelecidos com intervalo de sete dias, sendo M0 (imediatamente antes do início do tratamento com cloreto de amônio), M1 (sete dias após), M2, M3, M4, M5 e M6, totalizando 56 dias de confinamento. A alimentação consistiu de ração total, composta por 15% de feno triturado e 85% de concentrado, água e sal mineral ad libitum. Após adaptação de 15 dias à dieta de confinamento, colheram-se de todos os animais amostras de urina para mensuração do pH, e sangue venoso para hemogasometria, nos diferentes momentos. A acidificação urinária foi mantida enquanto houve a administração de cloreto de amônio nos grupos GI e GII. Os valores de Na+ e K+ permaneceram dentro da normalidade para a espécie. O cloreto de amônio provocou acidose metabólica hiperclorêmica compensada nos grupos GI e GII, comprovada pelos valores reduzidos de HCO3-, EB e SID, pelos valores elevados de Cl- e pelo pH normal. Concluiu-se que o cloreto de amônio apesar de provocar diminuição da reserva alcalina no organismo, não interferiu com o desenvolvimento dos animais, podendo ser empregado como agente preventivo da urolitíase obstrutiva em ovinos.