Prediction of methane emissions from fattening cattle using the methane-to-carbon dioxide ratio

This study aimed to develop a prediction equation for methane (CH₄ ) emissions from fattening cattle based on the CH₄ /carbon dioxide (CO₂ ) ratio and validate the predictive ability of the developed equation. The prediction equation was developed using the CH₄ /CO₂ ratio combined with oxygen consumption and respiratory quotient estimations that were theoretically calculated from the relation between gas emissions and energy metabolism. To validate the prediction equation, gas measurements in the headboxes were conducted using eight Japanese Black steers. The predictive ability of the developed equation was compared with that of two previously reported equations. As a result, the developed and reported equations had significant (P < 0.01) linear relationships between the observed and predicted CH₄ emissions. Notably, only the developed equation had a significant (P < 0.01) linear relationship between the observed and predicted CH₄ emissions when expressed per unit of dry matter intake. The results suggest that the developed prediction equation has a higher predictive ability than previously reported equations, particularly in evaluating the efficiency of CH₄ emissions. Although further validation is required, the equation developed in this study can be a valuable tool for on-farm estimations of individual CH₄ emissions from fattening cattle.

Large Group Housing Systems in Fattening Bulls-Comparison of Behavior and Performance

According to international housing recommendations, fattening bulls should not be housed in groups of more than 12-20 animals. However, there are no scientific studies supporting these recommendations as most studies on fattening cattle refer to smaller groups. Therefore, the aim of this study was to analyze and compare behavior and performance of 187 fattening bulls housed in different group sizes of 16, 22, and 33 animals. Behavioral observations were performed during three observation periods at an average age of 8.5, 13, and 17 months. Furthermore, body condition, health status and carcass weights were analyzed. Effects of increasing group size were observed regarding more synchronized lying behavior, longer lying durations and more undisturbed feeding and lying behavior. Interindividual variations in lying and feeding as well as mean and maximum percentages of animals participating simultaneously in interactions did not increase with group size. Health and growth performance were satisfactory in all group sizes. Therefore, the results of this study do not provide scientific evidence for the common argument that increasing group size leads to increased aggression. Furthermore, these findings indicate large group systems to be suitable for the housing of fattening cattle and to contribute to increasing animal welfare. Consequently, current recommendations should be revised.

Effect of pineapple stem starch feeding on rumen microbial fermentation, blood lipid profile, and growth performance of fattening cattle

Pineapple stem starch (PS) was evaluated for its suitability as a new starch source in concentrate for fattening cattle, based on the growth performance, blood profile, and rumen parameters of 36 steers in a 206-day feeding study. PS was formulated as a 40% concentrate and fed with forage in comparison with ground corn (GC) and ground cassava (CA) formulated at the same level. PS feeding improved weight gain and feed conversion ratio without affecting feed intake. PS did not obviously influence blood lipid profiles throughout the experiment. Ruminal concentration of total short-chain fatty acids (SCFA) increased with PS without affecting SCFA composition throughout the feeding study. Rumen amylolytic group, especially Ruminococcus bromii, was dominant in the rumen microbial community, and showed increased abundance by PS feeding throughout the experiment. These results clearly indicate the potential of PS as a useful starch source for fattening cattle in terms of rumen fermentation and growth performance.

Expression levels of brown/beige adipocyte-related genes in fat depots of vitamin A-restricted fattening cattle1

Brown/beige adipocytes dissipate energy as heat. We previously showed that brown/beige adipocytes are present in white adipose tissue (WAT) of fattening cattle. The present study examined the effect of vitamin A restriction on mRNA expression of brown/beige adipocyte-related genes. In Japan, fattening cattle are conventionally fed a vitamin A-restricted diet to improve beef marbling. Twelve Japanese Black steers aged 10 mo were fed control feed (n = 6) or vitamin A-restricted feed (n = 6) for 20 mo. Subcutaneous WAT (scWAT) and mesenteric WAT (mesWAT) were collected, and mRNA expression levels of molecules related to the function of brown/beige adipocytes (Ucp1, Cidea, Dio2, Cox7a, and Cox8b) as well as transcriptional regulators related to brown/beige adipogenesis (Zfp516, Nfia, Prdm16, and Pgc-1α) were evaluated. The vitamin A restriction significantly increased or tended to increase expression levels of Cidea and Pgc-1α in scWAT, and Cidea, Dio2, and Nfia in mesWAT. Previous studies revealed that the bone morphogenetic protein (Bmp) pathway was responsible for commitment of mesenchymal stem cells to brown/beige adipocyte-lineage cells. The vitamin A restriction increased expression of Bmp7 and some Bmp receptors in WAT. The interrelationship between gene expression levels indicated that expression levels of Nfia, Prdm16, and Pgc-1α were closely related to those of genes related to the function of brown/beige adipocytes in scWAT. Also, expression levels of Nfia, Prdm16, and Pgc-1α were highly correlated with those of Alk3 in scWAT. In summary, the present results suggest that the vitamin A restriction increases the number or activity of brown/beige adipocytes through regulatory expression of transcriptional regulators to induce brown/beige adipogenesis, especially in scWAT of fattening cattle, which may be governed by the Bmp pathway.

Feeding Behavior of Fattening Bulls Fed Six Times per Day Using an Automatic Feeding System

The usage of automatic feeding systems (AFS) in cattle offers multiple advantages, mostly due to the possibility of an increased feeding frequency. While it is gaining more and more importance in dairy farming, there is still a lack of experience and scientific knowledge regarding its use in fattening cattle. The aim of this study was to describe the behavior of 56 Simmental bulls fed with an AFS six times daily a total mixed ration. The animals arrived at the farm with an average age of 148 ± 11 days. They were housed in four straw-bedded pens in groups of 14 animals each. Their average slaughter age was 558 ± 20 days. Behavioral observations were made during three observation periods (OP) at an average of 11, 14, and 16 months of age. Using scan sampling, feeding, and lying behavior of all animals and the order of bulls feeding after feed delivery were recorded. Furthermore, body condition and health status were monitored and complemented with the carcass weights. Body condition, health status, and carcass weights of the bulls were found to be satisfactory: Mean body condition score increased from 2.8 ± 0.3 in OP1 to 3.0 ± 0.1 in OP3 and mean carcass weight was 432.71 ± 40.82 kg. No severe health problems occurred. The feeding activity of the bulls was spread out over the course of the day with peaks in the afternoon and evening. Percentages of bulls feeding per pen never exceeded 20%, animals feeding mostly alone (during 28.04 ± 2.15% of total observation time) or in groups of two to three (16.61 ± 2.00% and 6.74 ± 1.90%). The order of bulls feeding after feed delivery varied indicating that all animals had similar access to fresh feed. These results emphasize the importance of constant feed availability and quality at any time of the day, thus indicating the ability of an AFS with six daily feedings to ensure such a consistency.

Stereotypic Behavior in Fattening Bulls

The occurrence of stereotypies in captive animals may indicate restrictions in animal welfare. In cattle, common stereotypies are tongue playing, manipulation of objects, or conspecifics. However, to our knowledge, the occurrence of stereotypies in fattening cattle was only analyzed in studies several decades old. Therefore, this study aimed to analyze the prevalence of stereotypies in fattening bulls housed in different systems. On three German fattening farms, a total of 243 fattening bulls housed in groups of 14, 16, 22, and 33 animals in straw-bedded pens were observed. Behavioral observations were performed via video recordings during three observation periods distributed over the whole fattening period, using a scan sampling technique. In 234 of 243 bulls, stereotypies were observed at least once. During 15.9 ± 2.4% of the scan intervals, stereotypies were observed in at least one animal per pen. Average numbers of stereotypies per animal and hour ranged from 0.2 to 0.9. The most common stereotypy was manipulating objects, followed by tongue playing and manipulating conspecifics. These results indicate that stereotypies are highly prevalent in fattening bulls under current housing conditions. They underline the need for further studies to analyze the causation of stereotypies in order to reduce their frequency.

Grooming Device Effects on Behaviour and Welfare of Japanese Black Fattening Cattle

Simple Summary

Fattening cattle housed at a private farm in Japan were provided with a grooming device (a brush) during the late fattening stage. Behavioural observation revealed that the environmental enrichment stimulated the animals’ self-grooming and enabled them to scratch more body parts. Viscera disease was not detected in the enrichment animals when they were slaughtered. Environmental enrichment for fattening cattle can be used to satisfy their motivation to perform self-grooming and to improve their welfare.

Abstract

In livestock farming, a stark or barren environment compromises animal welfare. Environmental enrichment has been used to address the issue. For this study, after fattening cattle were provided with a grooming device (a brush), its effect on animal self-grooming and welfare were investigated. For Research trial 1 and 2, respectively, 28 and 11 Japanese Black steers were observed. Three or four of the animals were group-housed in a pen. For Trial 1, half of the animals were provided with a brush. The animals’ behaviour, carcass weight, and Viscera disease were recorded. Enrichment animals (E) performed self-grooming and scratching of the animals’ body on the brush and pen structures more than control animals (C) did (mean time budgets, 3.34% (SD = 2.48) in E and 0.89% (SD = 0.81) in C, GLMM, z value = 8.28, p < 0.001). The number of animals in which viscera disease was detected after slaughter was lower in E than in C (E = 0, C = 4, a Fisher’s exact probability test, p = 0.03). In Trial 2, brush use behaviour was observed continuously for 72 h. The observation revealed that the animals scratched various body parts on the brush. Results show that providing a brush as environmental enrichment improves welfare by satisfying the motivation of fattening cattle to perform self-grooming.