Growth performance, carcase characteristics and meat quality of crossbred bulls and heifers from double-muscled Belgian Blue sires and Brown Swiss, Simmental and Rendena dams

Growth, conformation, carcase and meat quality traits of crossbred calves obtained in the Alps from selected Belgian Blue sires (BB) and Brown Swiss (BS), Simmental (Si) and Rendena (Re) dams were studied, emphasising differences on dairy and dual purpose maternal breed. Six pens with five heifers (3 BB BS, 1 BB Si, 1 BB Re) and six pens with four young bulls (2 BB BS, 1 BB Si, 1 BB Re) were used. In total 53 crossbred calves were tested: 30 from BS dams and 23 from dual purpose (12 from Si and 11 from Re dams). Growth performances were measured, carcases were scored for muscle conformation and fatness, the fifth rib was dissected, and the Longissimus thoracis (LT) was analysed. The maternal breed had significant effects when the calves from dairy cows (BB BS) were compared to those of the dual pur- pose breeds (BB Si and BB Re), as at slaughter the former were 1.2% taller, 6.0% less in vivo muscle score, 5.0% less carcase muscle score, with a 13% greater proportion of bone in the rib, and their LT had 12.5% less drip losses, but 3% greater cooking losses and 25% greater shear force. It was concluded that when using a BB as a sire, the dam breed has influ- ence on the growth performance traits of the derived crossbreds, but the major influence would regard the carcase and meat quality traits. In the Alps, these differences are reflected in different sold prices of the crossbred calves from dairy and dual purpose breeds at local auctions

Methodological factors affecting gas and methane production during in vitro rumen fermentation evaluated by meta-analysis approach

Effects of some methodological factors on in vitro measures of gas production (GP, mL/g DM), CH4 production (mL/g DM) and proportion (% CH4 on total GP) were investigated by meta-analysis. These factors were considered: pressure in the GP equipment (0 = constant; 1 = increasing), incubation time (0 = 24; 1 = 65 48 h), time of rumen fluid collection (0 = before feeding; 1 = after feeding of donor animals), donor species of rumen fluid (0 = sheep; 1 = bovine), presence of N in the buffer solution (0 = presence; 1 = absence), and ratio between amount of buffered rumen fluid and feed sample (BRF/FS; 0 = 64 130 mL/g DM; 1 = 130\u2013140 mL/g DM; 2 = 65 140 mL/g DM). The NDF content of feed sample incubated (NDF) was considered as a continuous variable. From an initial database of 105 papers, 58 were discarded because one of the above-mentioned factors was not stated. After discarding 17 papers, the final dataset comprised 30 papers (339 observations). A preliminary mixed model analysis was carried out on experimental data considering the study as random factor. Variables adjusted for study effect were analyzed using a backward stepwise analysis including the above-mentioned variables. The analysis showed that the extension of incubation time and reduction of NDF increased GP and CH4 values. Values of GP and CH4 also increased when rumen fluid was collected after feeding compared to before feeding (+26.4 and +9.0 mL/g DM, for GP and CH4), from bovine compared to sheep (+32.8 and +5.2 mL/g DM, for GP and CH4), and when the buffer solution did not contain N (+24.7 and +6.7 mL/g DM for GP and CH4). The increase of BRF/FS ratio enhanced GP and CH4 production (+7.7 and +3.3 mL/g DM per each class of increase, respectively). In vitro techniques for measuring GP and CH4 production are mostly used as screening methods, thus a full standardization of such techniques is not feasible. However, a greater harmonization of analytical procedures (i.e., a reduction in the number of available protocols) would be useful to facilitate comparison between results of different experiments

Changes of particle size distribution and chemical composition of a hay-based ration offered once or twice daily to dairy cows

The objective of this experiment is to evaluate the changes of particle size distribution and chemical composition of the total mixed ration (TMR) based on hay as the main forage component ("dry" TMR) and distributed once (7.00 am) or twice (7.00 am and 1.00 pm) daily to 32 lactating cows. The trial was divided in two periods of 14 days each. Diet (DM=53.7%) was formulated in order to assure the nutritional requirements of cows producing 24 kg/d of milk (crude protein=14.4% DM; NDF=40.9% DM; milk FU=0.88/kg DM) and additional amounts of concentrates were distributed using automatic feeders. Four TMR samples were collected daily (7.00 am, 10.00 am, 1.00 pm, 4.00 pm) for six days during each experiment period for a total number of 48 feed samples. Each feed sample was subjected to the estimation of the particle size distribution using the separator of Pennsylvania State University composed of two sieves (diameters of 19 and 8 mm) and a collector on the bottom, and to the determination of the chemical composition. Changes of all three particle size fractions for TMRs were observed during the day with distributions of the TMR both once and twice daily. With the once daily distribution, the large particles fraction increased linearly (P<0.001) from 19.7 to 23.4, 32.2, and 35.1%, while the finest particle fraction decreased (from 60.1 to 58.3, 50.0, 47.8%). According to particle size changes, the chemical composition varied significantly at the different times of sampling when TMR was distributed once daily. Significant variations of DM were detected for TMR with a linear (P<0.001) increase (from 54.4 to 57.9, 60.7, 61.5%). Considering once TMR distribution, the values of NDF and starch showed an opposite trend with an increase of 6.5 and a decrease of 8.3 points from 7.00 am to 4.00 pm (i.e., 9 hrs after distribution). Correlations were estimated between chemical and physical characteristics of TMRs. NDF content was positively and significantly correlated to the fraction of particles retained by a 19 mm sieve (r=0.42; P<0.001) and negatively correlated with the smaller particles (r=-0.51; P<0.001). In conclusion, when the TMRs are prepared excluding corn/hay silages, twice daily distributions of diet can avoid the selection of large feed by the cows, thereby preserving both a uniform particle size distribution and a steady chemical composition of the diet during the day. However, the cost for the extra time needed for twice daily dis- tribution should be carefully considered

Relationships between in vivo Measurements of Backfat Thickness and Several Carcass and Ham Traits in Heavy Pigs

This study investigated the relationships between ultrasound measurements of backfat thickness (UBF) taken on live heavy pigs and several carcass composition and ham quality traits. Before slaughter 240 pigs were weighed (average BW: 167 ±10 kg) and assessed for UBF using an A-mode ultrasonic device (placed above the last rib at approximately 5.5 to 8.0 cm from midline, with increasing distance with increasing BW). At slaughterhouse backfat thickness and weight of carcass and of commercial lean and fat cuts were collected. Aft er 24-h chilling, hams were trimmed, weighed, scored and measured for several quality traits. A sample of trimmed fat was taken to assess iodine number and linoleic acid content. All hams were cured, and weight losses during curing were recorded. The measures of UBF were correlated with all carcass and ham traits available. The strongest relationships with UBF were detected for backfat depth at loin (0.54), backfat weight and yield (0.69), overall yield of lean and fat cuts (-0.59 and 0.51, respectively), score or measure of ham fat covering thickness (0.62 and 0.53, respectively), and linoleic acid content of ham subcutaneous fat (- 0.48). Magnitude of correlations does not provide reliable prediction of carcass, but ultrasound assessment on live animals could be useful to support selection programs of heavy pigs aimed to dry-cured ham production. Further studies are needed to investigate genetic relationships between these traits and UBF

Relationships between in vivo Measurements of Backfat Thickness and Several Carcass and Ham Traits in Heavy Pigs

This study investigated the relationships between ultrasound measurements of backfat thickness (UBF) taken on live heavy pigs and several carcass composition and ham quality traits. Before slaughter 240 pigs were weighed (average BW: 167 ±10 kg) and assessed for UBF using an A-mode ultrasonic device (placed above the last rib at approximately 5.5 to 8.0 cm from midline, with increasing distance with increasing BW). At slaughterhouse backfat thickness and weight of carcass and of commercial lean and fat cuts were collected. Aft er 24-h chilling, hams were trimmed, weighed, scored and measured for several quality traits. A sample of trimmed fat was taken to assess iodine number and linoleic acid content. All hams were cured, and weight losses during curing were recorded. The measures of UBF were correlated with all carcass and ham traits available. The strongest relationships with UBF were detected for backfat depth at loin (0.54), backfat weight and yield (0.69), overall yield of lean and fat cuts (-0.59 and 0.51, respectively), score or measure of ham fat covering thickness (0.62 and 0.53, respectively), and linoleic acid content of ham subcutaneous fat (- 0.48). Magnitude of correlations does not provide reliable prediction of carcass, but ultrasound assessment on live animals could be useful to support selection programs of heavy pigs aimed to dry-cured ham production. Further studies are needed to investigate genetic relationships between these traits and UBF

Effects of sugar beet pulp on growth and health status of weaned piglets

The effects on growth performance and on some health parameters due to the inclusion of sugar beet pulp in antibioticfreediets for weaned piglets were evaluated on a commercial farm. A conventional diet (C) and one containing 120 g/kgof sugar beet pulp (SBP) were fed to 668 weaned piglets from 21 to 64±3 days of age. Every two weeks, live weight andfeed consumption (FC) of the two groups were recorded by pens. Fecal samples were collected from 8 pairs of piglets foreach treatment to evaluate the evolution over the time of the apparent digestibility of the nutrients, as well as the volatilefatty acids content and the microbial count in the feces. The dietary treatment did not affect FC. In comparison to C, SBPslightly reduced average daily gain over 36 to 49 (528 vs. 498 g/d; P<0.05) and 50 to 64±3 (677 vs. 631 g/d, respectively;P<0.01) days of age. Digestibility of NDF of diet C increased with age from 441 to 526 g/kg whereas that of dietSBP increased from 465 to 638 g/kg. The differences between diets became significant after 36 days of age (P<0.01).From 29 to 35 days of age higher contents of water (793 vs. 713 g/kg; P<0.01), acetic (322 vs. 206 μmol/g dm; P<0.01)propionic (108 vs. 81 μmol/kg dm; P<0.01) acids and lower counts for fecal-coliforms (6.9 vs. 8.2 log10/g; P<0.01),clostridia (1.3 vs. 2.3 log10/g; P<0.01) and Staphylococcus spp. (6.7 vs. 8.1 log10/g; P<0.01) were found in the feces ofthe SBP piglets compared to those of C. These differences progressively disappeared with time. Some piglets showedclinical signs of purulent arthritis and meningitis, but no signs of diarrhea were observed. The SBP group showed, withrespect to C, a significantly lower number of piglet deaths caused by meningitis (15 vs. 30 ‰, respectively; χ2, P<0.05),and a significantly lower number of piglets removed because lack of growth (33 vs. 76 ‰, respectively; χ2, P<0.01). Noclear evidence to explain this result was found, however it was concluded that the inclusion of 12% of sugar beet pulpin antibiotic-free diets can improve the health status of piglets with little effect on growth performance

Short communication: Dietary protein restriction and conjugated linoleic acid supplementation in dairy cows affect milk composition, the cheese-making process, and cheese quality

We used 20 mid-lactating Holstein cows, housed in 4 pens according to a Latin square design, to evaluate the effects of dietary protein restriction (crude protein: 12.3 vs. 15.0% dry matter) and conjugated linoleic acid supplementation (CLA: 6.34 g/d of C18:2cis-9,trans-11 and 6.14 g/d of C18:2trans-10,cis-12) on milk composition, coagulation, curd firming and syneresis modeling, and cheese yield and quality (96 small cheeses). Dietary crude protein restriction, suggested as a way to reduce N excretion in farming, caused a reduction in milk protein content (-4%,), milk casein (-3.8%), lactose (-1%), cheese soluble protein (-16.8%), and the cheese maturation index (-15%), and a correlated increase in cheese fat content (+7.5%) and the fat to protein ratio (+18%). A modest reduction (-0.9%) in milk fat recovery in the curd did not affect cheese yield. The addition of CLA to the cows' diet, suggested as a way to improve N use efficiency and the nutritional value of dairy products, caused substantial alterations to the milk composition, cheese-making process, and cheese quality. The CLA reduced the fat (-12.3%), protein (-2%), casein (-2.2%), lactose (-1.0), and total solids (-4%) contents of milk, tended to delay coagulation, and weakened curd firming. The CLA reduced the fresh cheese yield (-7.5%) and cheese solids (-8.2%) because of the lower nutrient content of the milk, but also because of a lower recovery of milk protein in the curd (-0.9%) and lower total solids (-4.5%). It also reduced the fat content in the ripened cheese (-11.8%), as well as the fat to protein ratio (-19.4%) as a result of having increased the protein content (+9.3%). Last, it increased the lightness of the paste of the ripened cheeses (+3.3%), and especially the shear force (+16.3%). Dietary crude protein restriction, and CLA addition in particular, substantially altered the milk composition, cheese-making process, and cheese quality, and therefore needs to be carefully evaluated. Further studies are required to shed light on the causes of these modifications

a simplified approach to calculate slurry production of growing pigs at farm level

A simplified approach to predict the amount of slurry produced by growing pigs at farm level is proposed. The inputs are initial (LWi) and final (LWf) live weights, production (t) and empty (empty) periods, feed consumption (FC), dry matter (DMD), N digestibilities and farm water consumption per pig (FWC). Estimates of the amount of water required (or arisen) per kg of feed for the various physiological functions were estimated by running a published mathematical model using data representing the ordinary conditions of rearing. Water excretion was estimated in two ways depending on: 1) free access (ad lib) to water; 2) restricted access (forced). In the first case, the proportion of water consumed (wiad lib) and those excreted with the urine (wuad lib) and the faeces (wfec) were quantified to be 2.9, 1.72 and 0.33 kg per kg of feed, respectively. From the urinary excretions of N and minerals, obtained as the difference between the digestible nutrient intakes and the retentions, the model predicted a urinary DM content of 2.1% (by weight). In the second case, for pigs receiving drinking water in forced ratio with the feed (wiforced), the urinary production was calculated as wuforced=(wiforced+wf+wo)-(wd+ws+wg+wfec+we), where wf=water content in feed (0.12 kg/kg), wo=water arising from nutrient oxidation (0.25 kg/kg), wd=water required for digestion (0.08 kg/kg), ws=water demand for protein and lipid synthesis (0.06 kg/kg), wg=water retained in body tissues (0.14 kg/kg) and we=water lost through evaporation (0.96 kg/kg). Estimates of fresh slurry production (faeces+urine) were regressed against the values resulting from empirical literature equations and referred to pigs fed water:feed ratios of 2.5:1, 2.9:1 and 4:1. The resulting regression (R2=0.97), with a slope close to unity (1.05), indicated that the approach can be extended to predict the farm fresh slurry production with pigs having free access to water or kept on different water:feed ratios. In agreement with international literature, but not with the current Italian national standards, estimates of mature slurry productions ranged from 1.5 to 2.9 ton/pig/year with DM contents ranging from 8.3 to 3.7%. At farm level the use water meters is recommended as from FWC minus the estimated water consumption (FWCexp) the farmer can evaluate the extra wastage and adjust the predicted mature slurry production

Effects of water extracts from chicory and BHT on the in vitro rumen degradation of feeds.

Effects of Butyl-Hydroxyl-Toluene (BHT) and of Red Chicory Extract (RCE) on kinetics of gas production (GP) and rumen degradability values (OMd, NDFd and in vitro true OM degradability - IVTOMD) of two feeds (meadow hay and corn meal) were evaluated using an in vitro automatic batch system. For each feed 2 increasing dosages (0.15 and 1.5 mg/g of feed) of BHT and RCE and a Control (C) were tested in 4 replications and 2 incubations. First incubation lasted 72h, the 2nd one was stopped at the times on which half of GP was produced (t½), which were 9 and 16 h for corn and hay, respectively. From the supernatants of the 2nd incubation, VFA, NH3, N content of the residual NDF were analysed and the microbial N balance was computed. The 2 feeds significantly affected rumen fermentation parameters; BHT significantly increased asymptotic GP, t½ and IVTOMD (P<0.01), decreased the proportion of butyrate (P<0.01) but did not affect microbial N balance; RCE did not influence any of the parameters measured with respect to C, except for a significant increase of the estimated N available for microbes at the higher dosage

Nitrogen and energy partitioning in two genetic groups of pigs fed low-protein diets at 130 kg body weight

The aim was to evaluate the effect of low-protein (LP) or low-amino acid diets on digestibility, energy and nitrogen (N) utilisation in 2 genetic groups (GG) of pigs (129±11 kg BW). Duroc×Large White (A) pigs were chosen to represent a traditional GG for ham production, and Danbred Duroc (D) pigs to represent a GG with fast growing rate and high carcass lean yield. Dietary treatments: a conventional diet (CONV) containing 13.2% CP, and two LP diets, one with LP (10.4%) and low essential AA (LP1), the second with LP (9.7%) and high essential AA (LP2). Compared to CONV, LP2 had the same essential AA content per unit feed, while LP1 the same essential AA content per unit CP. Feed was restricted (DMI=6.8% BW0.75). Four consecutive digestibility/balances periods were conducted with 24 barrows, 12 A and 12 D. Metabolic cages and respiration chambers were used. No significant difference between diets was registered for digestibility. Nitrogen excreted: 41.3, 33.4 and 29.0 g/d (P=0.009), for CONV, LP1 and LP2 diets, respectively. Nitrogen retention was similar between the diets. Heat production (HP) was the lowest for LP diets. There was a tendency (P=0.079) for a lower energy digestibility in D group. The D pigs also had a higher HP and hence a lower retained energy in comparison with the A pigs. In conclusion: it is possible to reduce N excretion using very LP diets and LP-low AA diets; Danbred GG have a higher heat production and a lower energy retention than A pigs