A Survey on Feedlot Performance of Purebred and Crossbred European Young Bulls and Heifers Managed Under Intensive Conditions in Veneto, Northeast Italy

Relationships between European carcass evaluation and Meat Standards Australia grading scheme applied to young beef cattle

The European carcass grading scheme (EUROP) places large emphasis on meat yield and therefore on quantitative traits such as carcass conformation and superficial fat coverage. However, it falls short in considering sensory properties and consumer satisfaction. In contrast, the Meat Standards Australia (MSA) grading scheme considers, among others, animals' ossification, marbling, and ultimate pH as primary indicators of beef eating quality. This study aims to characterize MSA carcass grading scheme applied to the Italian beef production system, considering its significant role in European beef market. The study involved 3204 Charolais, Limousin, and crossbred young bulls and heifers slaughtered in a commercial Italian abattoir. Data collection spanned a broad range of variables, including animal characteristics, MSA traits, and EUROP carcass grading traits. Regardless of the sex of the animal, no significant relationship was observed between MSA traits and EUROP carcass grading scores. Factors such as sex, age, and arrival season at the fattening unit significantly affected most of MSA traits. Females had significantly higher marbling score, and lower ossification score and hump height than males. Animals imported in autumn and winter had significantly lower marbling score, but similar ossification score compared to those imported in spring and summer. Older females had the highest marbling scores. While further research is needed to assess whether the MSA grading scheme can be adapted to all different European rearing systems, results of this study are a prelude to the potential benefits that the MSA grading scheme can bring to the European beef industry.

The Meat Standards Australia carcass grading site affects assessment of marbling and prediction of meat-eating quality in growing European beef cattle

The lack of consumer feedback on beef eating quality contributes to reduced beef consumption in Europe. The Meat Standards Australia (MSA) grading scheme can assess the palatability of beef carcasses usually graded at the 10th thoracic vertebrae. However, the European beef industry relies on late-maturing breeds usually cut at the 5th vertebrae due to commercial reasons. Data from 55 young bulls and heifers of late-maturing breeds were collected in an Italian slaughterhouse following the MSA guidelines at both carcass grading sites and sides. Intramuscular fat levels were assessed through two scores and used with other variables to feed the MSA model, which predicts the MSA index, the meat-eating quality scores (MQ4) for 5 muscles and for each carcass grading site × side combination. The scores were analyzed using a mixed linear model. A correlation analysis was conducted to predict the variables measured at the 10th site using their correspondent at the 5th carcass grading site. A stepwise regression was conducted to understand the weight of each measured variable on marbling and MQ4 scores measured both at 5th and 10th carcass grading sites. Results showed significantly higher value for the studied traits at the 5th carcass grading site, while carcass side had no significant impact. The equations had high predictive capability and MSA marbling score played a key role in explaining the variability across carcass grading sites. The differences in marbling and MQ4 scores between the carcass grading sites suggest considering this factor if the MSA grading system will be applied to Europe.

Effects of vaccination timing and target pathogens on performances and antimicrobial use in long-transported Charolais beef cattle from France to Italy - A retrospective study

Antimicrobial use (AMU) in the livestock sector is a major driver of antimicrobial resistance. Italian beef industry strongly relies on the import of young cattle from France, which are commingled in sorting facilities before transportation to Italy. Both commingling and transportation are stressors for animals and lead to higher risk of bovine respiratory disease (BRD), which in turn increases the risk of AMU. This study aimed to investigate how the timing of first BRD vaccination and the different vaccination target pathogens affect AMU and performance of young Charolais beef cattle imported from France to Italy. Information on animal performance, antimicrobial treatments, and vaccinations was available for 60,726 Charolais cattle belonging to 1449 batches in 33 Italian specialised fattening farms between January 2016 and December 2021. Antimicrobial use was estimated using the treatment incidence 100 adapted for Italy (TI100it). A mixed linear model was used to quantify the effects of the vaccination and the time of first administration on slaughter age, carcase weight, and average daily carcase gain. Similarly, a generalised linear mixed model was used to analyse the TI100it. The vaccination programme was usually applied the first day after the animals' arrival to the Italian fattening farms. Most animals were vaccinated with a polyvalent vaccine against infectious bovine rhinotracheitis (IBR), bovine parainfluenza type 3 virus (PI-3), bovine viral diarrhoea virus type 1 and 2 (BVDV), and bovine respiratory syncytial virus (BRSV). The most used class of antimicrobials to treat BRD were the macrolides, followed by aminoglycosides, amphenicols, tetracyclines, aminopenicillins, and fluoroquinolones. Animals that got vaccinated against any of the considered BRD pathogens upon arrival had significantly lower TI100it, greater average daily carcase gain, and reached slaughter age earlier than animals that got vaccinated later. Animals that received the vaccination against BVDV had lower TI100it and greater average daily carcase gain, and animals that received the vaccination against BRSV were younger at slaughter than unvaccinated animals. The vaccination against Mannheimia haemolytica significantly decreased the slaughter age and increased the carcase weight and average daily carcase gain, and the vaccination against PI-3 and Histophilus somni significantly increased the slaughter age. Thus, even if the vaccination programme is essential to tackle BRD, this practice is questionable if applied at arrival to the Italian fattening farms and it is advisable that the vaccination programme is planned before the commingling procedure in France.

Temperature and humidity index (THI) affects salivary cortisol (HC) and dehydroepiandrosterone (DHEA) concentrations in growing bulls following stress generated by performance test procedures

The hypothalamus-pituitary-adrenal axis response to a challenge was proposed for genetic selection of robust and resilient animals. As ACTH (adrenocorticotropic hormone) test and hormone measurements in blood may result impractical, it may be useful to measure salivary hormones in response to natural stressors, after an accurate biological validation, to control factors that could contribute to the response. We evaluated whether animal handling during performance test affects salivary HC and DHEA secretion and could be used for selection. We tested the effects of habituation to repeated handling and THI as putative bias. Bull calves (N = 273) undergoing performance test were sampled at 8-9 and 11-13 months (N = 101), 8-9 months (N = 131), or 11-13 months (N = 41). On each test day (D0), calves were isolated, conducted to a squeeze chute and immobilized for 6 min. Saliva samples were collected in the morning after feed administration (T0), and after 6 min immobilization in the squeeze chute (T1) for HC and DHEA measurement. Environmental temperature and relative humidity were recorded every hour from 1:00 h to 24:00 h during the 6 days before the performance test and on D0. Salivary HC and DHEA concentrations were higher in T1 (p < 0.01), although a clear individual positive response to handling could be observed in less than 10% of subjects. The mixed model revealed: (i) HC and HC/DHEA were higher in Young bulls (p < 0.05). (ii) The time of T0 sample collection significantly affected DHEA (p < 0.01) and HC/DHEA (p < 0.05). (iii) THI affected both steroids (p < 0.001) but not HC/DHEA. Spearman correlations suggested that THI weakly affected salivary HC at T0 only (ρ = 0.150, p < 0.01), while moderate statistically significant correlations were found between DHEA and THI at T0 (ρ = 0.316, p < 0.001), and T1 (ρ = 0.353, p < 0.001). Salivary HC and DHEA in response to handling procedures might identify subpopulations of subjects with sensitive HPA axis. Habituation to repeated handling played a role, as the hormone response was lower in older animals. Chronic exposure to high THI had a minor effect on salivary HC visible at T0. A more intense THI effect was observed on salivary DHEA concentrations at both T0 and T1, which should be worth of further investigations.

The Role of Quarantine on Post-Mortem Performances of Charolaise Young Bulls

Biosecurity is essential to prevent the spread of diseases in livestock animals such as the bovine respiratory disease which can lead to negative effects on growth performance, and carcass and meat quality, as well as to an increase of antimicrobial use. The aim of this study was to investigate the effects of the quarantine on post-mortem performances (hot carcass weight, dressing percentage, pH 60 min after slaughtering, carcass SEUROP conformation, and fat cover) of 576 Charolaise young bulls imported from France and fattened in specialized Italian farms. Approximately half of the animals followed a standard fattening procedure without initial quarantine upon arrival to Italy (NO-QUA) and the other half underwent a 30-day period of quarantine (QUA) since their arrival to the farm. Post-mortem performances and parenteral administration of antimicrobial use were recorded. NO-QUA animals had lower average daily gain and slaughter weight but scored higher for carcass SEUROP evaluation and pH than QUA animals (p < 0.05). NO-QUA received more than double the number of parenteral antimicrobial treatments than QUA animals for respiratory diseases (139 vs. 56). Overall, quarantine applied on-farm contributes to improve post-mortem performances while reducing antimicrobial use in beef production.

Promoting Judicious Antimicrobial Use in Beef Production: The Role of Quarantine

Judicious antimicrobial stewardship in livestock industry is needed to reduce the use of antimicrobials (AMU) and the associated risk of antimicrobial resistance. Biosecurity measures are acknowledged for their role against the spread of diseases and the importance in reducing AMU in different species. However, their effectiveness in beef production has been scarcely considered. The aim of this study was to investigate the effect of the quarantine strategy on AMU in beef cattle. A total of 1206 Charolaise animals in five farms were included in the trial. Roughly half of the animals followed the standard procedure of the fattening cycle (no-quarantine; NO-QUA group) and half followed a 30-day period of quarantine (QUA group) since their arrival. Performance and antimicrobial data were recorded and a treatment incidence 100 (TI100it) per animal was calculated. Penicillins was the most used class of antimicrobials. Differences between groups were significant for males only, with NO-QUA group having greater TI100it (3.76 vs. 3.24; p < 0.05) and lower body weight at slaughter (713.4 vs. 723.7 kg; p < 0.05) than QUA group. Results suggest that quarantine strategy can reduce AMU in males without compromising their performance, whereas further investigation is needed for females.

Correlation of Breed, Growth Performance, and Rumen Microbiota in Two Rustic Cattle Breeds Reared Under Different Conditions

The use of rustic cattle is desirable to face challenges brought on by climate change. Maremmana (MA) and Aubrac (AU) are rustic cattle breeds that can be successfully used for sustainable production. In this study, correlations between two rearing systems (feedlot and grazing) and the rumen microbiota, the lipid composition of rumen liquor (RL), and the growth performance of MA and AU steers were investigated. Bacterial community composition was characterized by high-throughput sequencing of 16S rRNA gene amplicons, and the RL lipid composition was determined by measuring fatty acid (FA) and the dimethyl acetal profiles. The main factor influencing bacterial community composition was the cattle breed. Some bacterial groups were positively correlated to average daily weight gain for the two breeds (i.e., Rikenellaceae RC9 gut group, Fibrobacter and Succiniclasticum in the rumen of MA steers, and Succinivibrionaceae UCG-002 in the rumen of AU steers); despite this, animal performance appeared to be influenced by short chain FAs production pathways and by the presence of H₂ sinks that divert the H₂ to processes alternative to the methanogenesis.

Assessment of Rumen Mucosa, Lung, and Liver Lesions at Slaughter as Benchmarking Tool for the Improvement of Finishing Beef Cattle Health and Welfare

Abattoir post-mortem inspections offer a useful tool for animal disease surveillance. The present cross-sectional study aimed at assessing the prevalence of rumen mucosa, lung, and liver lesions in 153 randomly selected batches of finishing beef cattle through a post-mortem inspection at the abattoir. At least 15 animals per batch were inspected at slaughter by two veterinarians for a total of 2,161 animals (1,376 bulls; 785 heifers) coming from 80 Italian commercial farms. Rumens were inspected by recording as binary variables (presence/absence) signs of hyperkeratosis, ruminitis, ulcer, and star scars. Similarly, lungs were inspected for signs of pneumonia and livers for signs of lipidosis, abscesses, and/or adherence. Hyperkeratosis of the mucosa and signs of ruminitis were detected in 58 and 30% of the inspected rumens, respectively. Ruminal star scars were more prevalent in bulls than in heifers (18 vs. 11%; P < 0.05). Signs of severe pneumonia were observed in 10% of the lungs; abscess and/or adherence in 4% of the livers. Hyperkeratosis of rumen mucosa was correlated to signs of ruminitis, and signs of ruminitis were correlated to star scars. No correlations were found between hepatic lesions and any other rumen or lung disorders. The wide variability observed among batches for the prevalence of specific lesions suggested the development of a benchmarking system to provide feedback to the farm veterinarians, as these lesions can be reflective of a subclinical disease status not easy to be detected in the live animal. Quartiles of the batch prevalence of rumen, lung, and liver alterations (if ≥1%) were calculated as a benchmarking tool, and third quartile value was proposed as an alarm threshold for each lesion. The use of the benchmarking system could allow to allocate each inspected batch to a specific "health class." Critical batches with a prevalence above the alarm threshold for a given lesion should be reported to veterinarians of the origin farms where actions should be taken in order to identify and lower the risk factors for that specific health issue. Knowledge of post-mortem inspection data along with the implementation of the proposed benchmarking system should help farm veterinarians to improve herd management from a health and welfare perspective.

Purebreeding with sexed semen and crossbreeding with semen from double-muscled sires to improve beef production from dairy herds: Live and slaughter performances of crossbred calves

The use of sexed semen to produce purebred replacement heifers allows a large proportion of dairy cows to be mated to beef sires, and quantitative and qualitative improvements to be made to beef production from dairy herds. The major dairy and beef breeds are undergoing rapid genetic improvement as a result of more efficient selection methods, prompting a need to evaluate the meat production of crossbred beef × dairy cattle produced using current genetics. As part of a large project involving 125 commercial dairy farms, we evaluated the combined use of purebreeding with sexed semen and crossbreeding with semen from beef sires, particularly double-muscled breeds. A survey of 1,530 crossbred calves revealed that, whereas purebred dairy calves are destined almost exclusively for veal production, beef × dairy crossbred calves are also destined for beef production after fattening on either the dairy farm of birth or by specialized fatteners. In veal production, compared with Belgian Blue-sired calves (taken as the reference), double-muscled INRA 95-sired calves had a lighter slaughter weight (303 vs. 346 kg), but a greater dressing percent (62.3 vs. 58.4%). Limousin (also known as Limousine)-sired calves had a smaller average daily gain (1.26 vs. 1.34 kg/d), and lighter slaughter (314 vs. 346 kg) and carcass weights (182 vs. 201 kg). Last, Simmental-sired calves had a similar growth rate, but lighter carcass weight (177 vs. 201 kg), smaller dressing percentage (55.3 vs. 58.4%), and smaller muscularity scores (3.25 vs. 3.72). In the case of young bulls and heifers fattened on the dairy farm of birth, Belgian Blue-, Piemontese (also known as Piedmontese)-, and Limousin-sired calves performed similarly; the only exception was that Piemontese-sired calves had a greater dressing percentage. Belgian Blue- and Limousin-sired calves performed similarly when fattened by specialized beef producers. In both veal and beef production, the effects of dam breed were less important than sire breed. Considering the entire project, we can conclude that the combined use of sexed semen for purebreeding and conventional beef semen for terminal crossbreeding improves meat production from dairy herds, especially when the sires are double-muscled beef breeds.

Exploring potential risk factors of antimicrobial use in beef cattle

Livestock species are major contributors to the increase of antimicrobial (AM) resistance which is a worldwide concern for both human and animal health. The over-use of AM is widely acknowledged, however, unlike pigs, poultry and dairy cattle, knowledge on potential risk factors affecting AM usage (AMU) in beef industry is limited. Hence, this study aimed to investigate the impact of farm, breed, sex and season of arrival of purchased beef cattle on AMU in Italian beef cattle. Data on 1063 batches were collected from January 2016 to April 2019 from specialised beef fattening farms located in the north of Italy. Information on breed, sex, date of arrival, performance traits and AM agents used on farm was collected, and the treatment incidence 100 (TI100) indexes per batch were calculated using the defined daily dose animal estimated according to Italian summaries of product characteristics. Factors affecting TI100 indexes were investigated using a cross-classified multilevel model. Farms largely differed in terms of AMU. Males had greater AMU than females (P < 0.001), likely due to their higher susceptibility to disease. Statistically significant differences were observed between seasons of arrival with summer and spring having lower TI100 indexes than winter and autumn (P < 0.001). Indeed, winter is commonly linked to an increase in respiratory diseases in beef cattle. Finally, the TI100it indexes tended to be different among breeds with Blonde d'Aquitaine and Limousine having greater AMU compared to the other breeds. Results of this study provided valuable information on potential risk factors of AMU in beef production which may be useful to address its reduction. For instance, the development of tailored management strategies for specific breeds, targeted approaches to improve the health of males as well as greater care towards batches purchased in winter are possible advice to implement on-farm for a more responsible AM stewardship.

Use of antimicrobials in beef cattle: an observational study in the north of Italy

Antimicrobial resistance is a worldwide issue whereby a more prudent use of medications is needed, especially for those antimicrobials (AM) classified as 'highest priority critically important antimicrobials' (HPCIAs) which are likely contributors to the development of resistance. So far, data on antimicrobial use (AMU) in EU are mainly reported at sales level while information on real use, mostly in beef production, is poor. The most reliable indicator to measure AMU is the treatment incidence (TI100) calculated by using the Defined Daily Dose Animal (DDDA) as stated by the European Medicines Agency (EMA). Although Italy ranks second among EU countries with regard to the AM sales in livestock production, data on AMU of the Italian beef production is still lacking, whereby the aim of this study was to provide information on the current scenario of AMU in Italian beef cattle. Data were collected from January 2016 to April 2019 from specialized beef fattening farms located in the north of Italy yielding a final dataset of 1376 batches. Data on performance and AM agents used in the study were collected and TI100 indexes per batch were calculated according to both Italian and EMA's DDDA. A Kruskal-Wallis test was used to check for differences between years and seasons. Results showed a significant variation between years and seasons with a reduction of TI100 based on Italian DDDA as time progressed (P < 0.05). However, about 40% of the total amount of treatments administered were HPCIAs with macrolides accounting for the 27.7% of the total amount. The most common reasons of administration of AM were respiratory diseases (68.9%) and lameness (17.6%). Penicillins was the class of AM used on the highest proportion of batches (84.4%) showing that broad-spectrum AM were widely exploited among herds. In summary, despite a general reduction of AMU in beef cattle over time, a great use of HPCIAs was still observed suggesting that AM stewardship for Italian beef production should pay particular emphasis on the reduction of HPCIAs use. This shows how overall knowledge on where efforts need to be optimized is important to develop targeted strategies for a more responsible AM stewardship. Results of the current study may also contribute to define national and EU benchmark criteria for AMU, as a comparison with studies carried out in other countries or on other food-producing sectors is still challenging to achieve.

Short communication: Pure-breeding with sexed semen and crossbreeding with semen from double-muscled sires to improve beef production from dairy herds: Weight and value of calves

The use of sexed semen to produce purebred replacement heifers allows a large proportion of dairy cows to be mated to double-muscled sires and for quantitative and qualitative improvements to be made to beef production from dairy herds. A survey of 1,285 crossbred calves showed that they are destined not only for veal production (like purebred dairy calves) but also for beef production. Crossbred calves obtained from Belgian Blue sires (sold on average at 34 d of age and 64 kg of weight) had a higher market value (€363/calf) than those obtained from double-muscled INRA 95 sires (€297/calf, used for veal production) and from Limousin sires (€216/calf for veal and €271/calf for beef production). As a sire breed, Simmental did not differ significantly from Belgian Blue, but as a dam breed, the crossbred calves fetched a higher price (€5.11/kg) than when Holstein was the dam breed (€4.50/kg). Compared with heifer calves, crossbred bull calves at sale were younger (34.1 vs. 37.2 d) and heavier (64.0 vs. 62.6 kg of live weight), fetched a higher price (€5.13 vs. €4.99/kg), and had a greater value (€328 vs. €312/calf). As the value of purebred dairy calves was about €80 to €100/calf, we are able to confirm that the combined use of sexed semen for pure-breeding and conventional beef semen for terminal crossbreeding can increase the income from dairy farms, especially when the sires are double-muscled beef bulls.

Protection of Animals during Transport: Analysis of the Infringements Reported from 2009 to 2013 during On-Road Inspections in Italy

Simple Summary

On-road inspections of vehicles that transport animals are mandatory in Europe. Infringements of the Council Regulation (EC) 1/2005 that were ascertained by competent authorities during on-road inspections published by the Italian Health Ministry from 2009 to 2013 were analyzed. The aims were both to identify possible routes or species that are more likely to be at risk of poor welfare conditions and to suggest recommendations. A total of 985 infringements were reported. For analysis, they were split into three main categories that were related to animal welfare (AW), vehicle (V), and accompanying documents (D). Each category was further classified under different subcategories (e.g., overcrowding for AW, lack of drinking system for V, and lack of health certificate for D). The most frequent infringements were related to D (34.4%), but more than one infringement was often found during an inspection (mean: 1.58; max: 9). A score (from 1 to 3) that was related to the severity of the animal-welfare issues was created which was found to be associated with year, species, authority, and country of dispatch (p < 0.001). Over the years, the only improvement was in the accompanying documentation. Vehicles that were transporting pigs, sheep, or goats were more likely to have the poorest welfare conditions, whilst vehicles that were transporting horses or other species, including dogs, were often found with irregular documentation. AW infringements were more likely to be uncovered during road inspections where traffic police and veterinarians worked together. This type of road inspection should be intensified so as to enhance animal welfare during transportation.

Abstract

Council Regulation (EC) No 1/2005 requires that vehicles that are transporting animals be subjected to checks conducted by competent authorities. Yearly, each member state sends a report to the European government on the infringements that have been discovered during on-road inspections. The reports that were published by the Italian Ministry of Public Health from 2009 to 2013 were analyzed. Possible associations between the type of infringement (related to animal welfare (AW), vehicle (V) and accompanying documents (D)), year, season, transported species, place of inspection, and competent authorities were identified. A total of 985 infringements were analyzed, with some vehicles receiving more than one (mean: 1.58; max: 9). A score (from 1 to 3) that was related to the severity of the infringements was created. In 2009 and 2010, there was a 50% higher probability of encountering penalties of a lower severity (D or V) than in 2011 (p < 0.0001). Vehicles that were transporting pigs showed the highest probability of committing animal welfare-related infringements (odds ratio (OR) = 3.85, 95% confidence interval (95%CI) = 1.82–8.76, p < 0.0001). Vehicles were four times more likely to suffer animal welfare-related penalties when traffic police worked in synergy with veterinary services (OR = 4.12, 95%CI = 1.70–11.13, p = 0.0005). Vehicles that were transporting Equidae and “other species,” including pets, for commercial purposes were more likely to be fined for a lack or incompleteness of the veterinary documents than those transporting cattle (p = 0.002 and p = 0.004, respectively). This study gives statistical evidence of the implementation of EC 1/2005. The training of transporters and drivers on how to manage transport in an animal welfare-friendly manner and a standardized method on how to conduct road inspections among competent authorities are recommended.

Risk factors for claw disorders in intensively finished Charolais beef cattle

This cross-sectional study aimed at performing a risk factor analysis of on-farm housing and management factors associated with infectious and non-infectious claw disorders of intensively finished Charolais young bulls and heifers. Claws' health condition of a total of 1305 animals belonging to 88 batches finished in farms located in the Eastern Po Valley (Italy) was assessed at slaughterhouse. Batch prevalence of feet affected by sole hemorrhage (SH) and white line abscess (WLA) was calculated and foot condition was summarized by infectious lesion (ILS) and non-infectious lesion (NILS) scores according to diseases' etiology. Batch prevalence of feet with SH, WLA, and assigned to the worst score classes were the outcomes in the risk factor analysis. Information about rearing facilities and health management of the tested batches were gathered in each origin farm along with a dietary sample used for chemical and physical analyses. Five categorized factors and 30 continuous covariates were considered as independent predictors and a cluster analysis of the continuous covariates was performed to select the most representative ones. Percentage of feet/batch affected by SH was on average 57.0 ± 32.5 % (SD) and by WLA was 9.94 ± 12.7 %. Percentage of feet/batch with the worst ILS and NILS was 29.6 ± 32.8 % and 12.5 ± 14.1 %, respectively. Charolais bulls showed a higher risk of SH and WLA than heifers and an increasing dietary NDF content acted as preventive factor. Concrete slats increased the risk of SH. Animals slaughtered in winter had the highest risk of WLA and the increasing level of dietary water-soluble carbohydrates (WSC) was a further risk factor. The risk for the worst NILS was lowest in spring and in presence of ventilation systems. It increased for bulls and in those batches fed diets with higher WSC content. Batches for which the farmer reported a higher prevalence of urgently slaughtered animals during finishing showed a higher risk of WLA and infectious claw diseases. The risk for infectious claw diseases was reduced in animals slaughtered in summer, housed on deep litter and fed diet with increased NDF content. It increased in farms where diet formulation was not under the nutritionist control. As general outcomes of the study, benefits for the claw health of finishing Charolaise may come from the use of the deep litter and ventilation systems, the involvement of a nutritionist in diet formulation, and the provision of diets with reduced WSC and increased NDF contents.

The Effects of Decreasing Dietary Crude Protein on the Growth Performance, Feed Efficiency and Meat Quality of Finishing Charolais Bulls

This study aimed to evaluate the effect of decreasing dietary crude protein (CP) on the performance of finishing Charolais bulls in the Italian rearing system. Animals were fed two diets, differing only in the CP level (low protein (LP), 13.5% CP versus control (CON), 15.0% CP). Dry matter (DM) intake (DMI) and animals' weights were recorded to obtain average daily gain (ADG) and feed conversion rate (FCR). Feed and fecal samples were collected to evaluate digestibility of diet components. Daily cost of the ration (DRC), feed cost per kg of daily weight gain (CDG) and daily gross margin (DGM) were calculated to analyze the possible benefits of decreasing the protein level. Meat quality analyses were also conducted. Higher DMI (10.6 versus 10 kg/d; p < 0.05) and ADG (1.47 versus 1.36 kg/d; p < 0.05) were observed for CON. No differences in FCR or digestibility were found. Even if the DRC was lower (p < 0.05) for the LP diet (2.26 versus 1.97 €; CON versus LP), no difference was reported for CDG and DGM. Meat lightness and redness were significantly lower and higher in the LP, respectively. To conclude, the CP requirement in these rearing conditions appeared to be higher than 13.5%.

Health, behaviour and growth performance of Charolais and Limousin bulls fattened on different types of flooring

Intensive fattening of late-maturing breeds on concrete or rubberized slatted floors is the prevalent beef production system in mainland Europe. The rationale behind this study is that specific beef breeds with different slaughter weights might have a diverse response to different flooring systems. The study aimed at assessing whether growth performance, health, behaviour and claw condition of two beef breeds, Charolais (CH) and Limousine (LIM), would be affected by their housing on concrete (CS) or rubber-covered (RCS) fully slatted floor. A total of 228 CH (116 on CS; 112 on RCS) and 115 LIM (57 on CS; 58 on RCS) were housed in four and two commercial farms, respectively, in groups of 9.0 ± 2.1 animals/pen with an average space allowance of 3.1 ± 0.2 m2. Draining gaps of CS and RCS pens were 16.9 ± 1.7% and 11.6 ± 1.2% of the total surface, respectively. Bulls of both breeds had similar initial body weight (429.4 ± 31.5 kg for CH; 369.6 ± 31.7 kg for LIM), and they were slaughtered when they reached suitable finishing. Charolais had a higher final body weight (BW) than LIM (750.8 ± 8.6 v. 613.7 ± 10.9 kg; P < 0.01), and bulls of both breeds on RCS had higher average daily gain than on CS (1.47 ± 0.02 v. 1.39 ± 0.02 kg/day; P < 0.05). The percentage of bulls early culled or treated for locomotor disorders were reduced by RCS only for LIM, while RCS tended to prevent the occurrence of bursitis for both breeds. During two 8-h behavioural observations, bulls on RCS performed more head butt/displacements and chases than on CS, and they reduced the frequency of abnormal lying down events. The use of RCS increased mounts' frequency only in LIM, while its reduced drainage capacity impaired only the cleanliness of CH. Postmortem hoof inspection showed longer claw dorsal wall and diagonal lengths, and sharper toe angles for CH on RCS than LIM on both floors. Results of this study point out that fully slatted floors, regardless of being rubberized or not, are not suitable for bulls finished at a final BW above 700 kg due to their detrimental effects on health and welfare. The use of RCS could be recommended as an alternative to CS only if bulls are slaughtered at a lower final BW (around 600 kg), like in the case of LIM breed.

Effects of breed and different lipid dietary supplements on beef quality

Focus of this study was to evaluate the most suitable breed/crossbred and the appropriate nutritional strategies to increase marbling in beef muscle and to improve its healthy properties, in particular the n-3 fatty acids content. One hundred and seventy-six heifers of three crossbreed commonly reared by Emilia-Romagna farmers: 48 Bleu Belge × Freisian (ITA), 48 Charolais × Aubrac (FRA), and 80 Angus (ANG) were used. Animals of each breed were randomly subdivided in two experimental groups that received two diets, differing for the dietary lipid source. Control group (C) received a basal diet containing protected vegetable fats, whereas treated one (T) received the same basal diet supplemented with 0.9 kg/head/day of extruded flaxseed. After slaughtering, a sample of Longissimus thoracis was collected from each animal for meat quality analysis. Our results demonstrated that, in a shorter fattening period, ANG animals obtained the best dry matter intake, average daily gain and the best fattening scores. ITA and ANG meat presented the highest marbling scores. ANG breed had the highest amount of C18:1, the highest unsaturated/saturated fatty acids ratio and the lowest n-6/n-3 ratio. The T animals, independently from breed, showed the highest amount of α-linolenic acid (ALA). In addition, ANG-T meat presented the highest ALA content.

Risk factors associated with beef cattle losses on intensive fattening farms in Austria, Germany and Italy

The aim of this study was to investigate management and feeding practices associated with on-farm loss rate (mortality) on 63 beef cattle farms in Austria, Germany and Italy with housing systems other than fully slatted pens. Information on mortality and 56 categorised factors relating to the cleanliness of animal facilities, health and feeding management, animal-human interaction, cattle transport and origin were gathered during on-farm visits. Samples of total mixed rations (TMRs) were collected and analysed for chemical composition and particle size distribution. Twenty-eight categorised factors were removed from the initial 56 due to exclusion criteria (missing data≥20% and/or monolevel factors with≥80% answers in one category). Mortality was the response variable in the risk factor analysis and the remaining 10 continuous covariates from TMR analyses and 28 categorised factors were independent predictors. Mean (±standard deviation) mortality, representing the proportion of dead, euthanased and early culled animals over the total number of animals bought in or reared in the previous year, was 2.8±3.5%. Fourteen factors were significantly associated with mortality in the bivariable analyses; seven factors were not considered further in the multivariable analysis due to collinearity. None of the factors related to TMR were associated with mortality. Four categorical factors, referring to biosecurity measures and management, were retained in the final multivariable model, with country effect. Buying cattle from only one farm, no mixing of animals during transport, presence of a dedicated sick pen and keeping production records were associated with lower percentage mortality.

Crossbred young bulls and heifers sired by double-muscled Piemontese or Belgian Blue bulls exhibit different effects of sexual dimorphism on fattening performance and muscularity but not on meat quality traits

As double-muscled Belgian Blue (BB) and Piemontese (PIEM) breeds are heavily selected for different objectives (the former mainly for muscularity, the latter for ease of calving), the aim of this study was to compare sexual dimorphism in 56 crossbred young bulls and heifers obtained from dairy cows mated to bulls of the two beef breeds. Young PIEM- and BB-sired bulls had similar fattening performances and beef traits, although the BB crossbreds were slightly more muscular. Otherwise, the BB-sired heifers exceeded the PIEM-sired heifers in growth rate (1.12 vs. 0.98kg/d), feed efficiency (0.129 vs. 0.121kg/kg DM), increases in muscle scores (1.45 vs. 0.98 SEUROP scores) and carcass yield (0.612 vs. 0.605), but not in fatness, retail cut proportions and meat quality traits. Sexual dimorphism is, therefore, less distinct in BB than in PIEM crossbreds. In conclusion, BB sires are to be preferred for "product quality", and PIEM sires for "process quality", on account of welfare and ethical issues.