Animal - Open Space最新文献

This study aimed to investigate factors that influence the use of concentrate in dairy farms based on farmers' perceptions of dairy system characteristics and relationships with the dairy industry. Data were collected through questionnaires administered on-site to 155 dairy farmers in Paraná State, Brazil. Partial least squares structural equation modeling was used to analyze the data. Dairy farmers' perceptions were measured by the theoretical constructs, concentrate feeding, forage, genetics, management, and market. The results revealed that dairy farmers' decision to adopt concentrate feeding was mainly determined by the genetic construct (defined by herd genetics and breeding technology) and the market construct (defined by the ability of farmers to negotiate milk prices with the industry and the number of interested buyers). Concentrate feeding was also found to be influenced by farmers' perceptions of the management construct (management of costs and animal performance) and the forage construct (forage source and farmers' self-confidence in providing forage to cows throughout the year). These findings suggest that strategies aimed at stimulating concentrate feeding in dairy farms should focus on the following factors (listed in order of importance): genetic improvement, farmer–industry relations, financial and herd management, and forage supply and availability.

The relational database SOWELL was created to better understand the behaviour and individual responses of gestating sows facing different short-term events induced: a competitive situation for feed, hot and cold thermal conditions, a sound event, an enrichment (straw, ropes and bags available) and an impoverishment (no straw, no objects) of the pen. The data were collected on 102 crossbred sows equipped with activity sensors, group-housed in video-recorded pens (16–18 sows per pen), with access to automatons. Feeding and drinking behaviours were extracted from the electronic feeders and drinkers’ recordings. Social behaviours, physical activities and locations in the pen were recorded thanks to manual video analysis labelling at the individual scale. Accelerometer fixed on the sows’ ears also recorded individual physical activities. The physical activity was also determined at a group scale by automatic video analysis using deep learning techniques. BWs, back fat thickness, and body condition (cleanliness, body damages) were recorded weekly during the whole gestation. Last gestation room data regarding environmental conditions (temperature, humidity, noise level) were recorded using automatic sensors. The database can fulfil different research purposes, namely sows’ nutrition for example to better calculate the energy requirements regarding environmental factors, or also on welfare or health during gestation by providing indicators.

Vulnerability has been a recurring theme in animal production research around the world, as it can lead to a series of outcomes, such as abandonment of the activity. Nevertheless, in Brazil, the fifth-largest milk producer in the world, studies assessing dairy farmers' vulnerabilities are scarce. Better understanding of dairy farm vulnerability may contribute to reducing the consequences of vulnerability. In view of these limitations, we sought to analyze the typology of dairy farms based on vulnerability characteristics. We applied on-site questionnaires to 128 dairy farmers located in Paraná State, Brazil. Structural, productive, and socioeconomic data were collected and subjected to factor analysis. Two vulnerability indicators were identified: F1, productive and economic indicator; and F2, feed self-sufficiency indicator. Hierarchical cluster analysis of factor scores revealed three groups of dairy farms: Group 1, highly vulnerable; Group 2, less vulnerable; and Group 3, non-vulnerable. Dairy farms with higher vulnerability represented most of the sample, followed by less vulnerable and non-vulnerable dairy farms. Our findings indicated that the productive and economic characteristics of farms contributed the most to explaining differences in vulnerability, followed by feed self-sufficiency characteristics. Social characteristics of farmers were not important in differentiating the analyzed sample. There was an interdependent relationship between vulnerability indicators, namely productive and economic characteristics and feed self-sufficiency.

Escherichia coli (E. coli) is an early organism in the colonization of mucosal tissue and has an influence on the development of mucosal and systemic inflammatory responses. To understand the impact of transfer of Immunoglobulin G (IgG), E. coli-specific antibody and general immune factors to the calf on the gut microbiota, an observational study that followed the temporal colonization of the intestine with E. coli as correlated with the total quantity of IgG and the antibody recognizing E. coli, was conducted in newborn Holstein calves. The calves were subjected to the “gold standard” of colostrum management, including dam vaccination prior to delivery to prime colostrum. Twenty Holstein dams, producing an adequate quantity of good-quality colostrum following uncomplicated deliveries of healthy female offspring, were utilized in this study. Each calf was monitored and scored daily for diarrhea. Blood and fecal samples were collected from calves on day (D) D1 (before colostrum intake), then D3, D7, D14 and D28 after colostrum feeding. E. coli isolated from fecal samples of the calves were assessed for virulence genes and the quantity per gram of feces using conventional Polymerase chain reaction and Real-time polymerase chain reaction quantitative, respectively. The total quantity of plasma IgG and the titer of E. coli-binding antibody were measured by enzyme-linked immunosorbent assay. The peak in diarrhea in the calves was observed on D12. No IgG or E. coli-binding antibody were detected prior to colostrum intake (D1). Both total IgG and binding antibody sharply increased by D3. Total and binding IgG declined with calf age. The total number of bacteria (16S rRNA) in feces was similar between D1 and D14. The number of total bacteria increased over the period from D14 to D28. The number of E. coli was minimal on D1. The number of E. coli increased during the period D3-D7. A decrease in the number of E. coli per gram of feces declines between D14and D28. The stable toxin gene was frequently identified in the E. coli isolated from the calves. Further, E. coli K99 was not identified in this study. While the gut was colonized by E. coli early in life corresponding to the peak level of IgG and specific antibody, a decreasing number of E. coli were observed as the passive immunity waned. This suggests that the function of the passive antibody may be to control colonization and seed innate immune function that then stabilizes the level of E. coli in the digestive tract of calves.

Providing rabbits with outdoor access allows them to express a large repertoire of behaviours and addresses societal expectations surrounding animal welfare in livestock systems. The aim of this work was to study rabbit growth, health, and behaviour according to genetic type and pasture area size. We distributed 192 weaned rabbits into two groups with different pasture sizes, i.e., a large pasture (LP): 60 m² (n = 4 × 24) and a small pasture (SP): 30 m² (n = 4 × 24). Each group contained half Californian 1001 × New Zealand 1777 rabbits (1001) and half PS119 × New Zealand 1777 rabbits (PS119). Rabbits were reared from 31 to 73 days of age. Rabbit growth and morbidity were measured individually weekly for 36 days (from 31 to 67 days of age). The rabbits’ behaviours were assessed three times a day on days 44, 58, and 70 by a direct visual scan, and the use of space was evaluated six times a week based on the rabbits’ spatial distributions. The available biomass was evaluated on days 35, 50, and 73. Finally, the amount of corticosterone was measured in hair samples from 18 rabbits of each genotype in LP and SP on day 72. PS119 rabbits were heavier than 1001 rabbits on day 67 (2 444 vs 2 113 g, respectively; P < 0.05) but we observed no effect of genotype on mortality or morbidity. The animals expressed a large variety of specific behaviours on pastures, with grazing and resting being predominant. We found a lower level of corticosterone in PS119 rabbits than in 1001 rabbits (2.19 vs 6.34 pg per mg of hair, respectively; P < 0.05). LP pastures offered herbage until the end of the fattening period, enabling the rabbits to express grazing behaviour until the end of the experiment, and grazing behaviour was more frequent in LP-group rabbits (25.4 vs 21.5% of occurrences in LP vs SP; P < 0.05). This study found that a pasture of 60 m² for 24 rabbits enables the animals to express grazing for the entire fattening period. The rabbit genotype was found to influence some of their behaviour.

Milk lipolysis is defined as the hydrolysis of triglycerides, which are the main component of milk fat. Short-chain fatty acids (FAs) released in milk are responsible for rancid flavour. In addition, the presence of partial glycerides impairs the functional properties of milk, such as foaming and creaming abilities. Milk lipolysis, a key criterion used to assess milk quality, depends on animal parameters and breeding factors. Low-energy diets are associated with higher levels of spontaneous lipolysis, particularly in late lactation. In this study, dairy cows were fed a restricted diet (i.e. 65% of their ad libitum DM intake (DMI)) to induce spontaneous lipolysis in milk and to study milk composition associated with lipolysis. Two groups of 22 cows each received a control diet (100% of ad libitum DMI) or the restricted diet according to a 2 × 2 crossover design. The restricted diet was fed for five days. As expected, feed restriction increased milk spontaneous lipolysis which was associated with an increase in lipoprotein lipase activity. At the same time, milk yield and protein content decreased and no effect was observed on milk fat content. The increase in spontaneous lipolysis was associated with an increase in milk fat globules diameter, without influencing casein micelles diameter. Feed restriction altered the parameters of dairy cow metabolism, with increases in plasma non-esterified FAs, triglycerides and urea, indicating body fat mobilisation and protein catabolism associated with feed restriction. Feed restriction also altered hormonal parameters, with decreases in plasma insulin, insulin-like growth factor 1 and prolactin. As expected, lipolysis was higher in evening milk and was associated with a larger diameter of milk fat globules. This zootechnical approach will be completed with proteomic, lipidomic and transcriptomic studies of milk and/or mammary gland of animals selected for their extreme lipolysis.

In the postnatal period, neonatal adaptation in terms of cardiovascular, respiratory, metabolic, thermoregulatory, and immunological functions is required, thus demanding the establishment of baseline parameters for research on neonatal calves. Few longitudinal studies have presented a set of physiological reference values for neonatal calves. The objective of this study was to evaluate physical, haematological, and biochemical parameters in young Holstein heifers in order to obtain useful information on their neonatal adaptation. Twenty-eight healthy young Holstein heifers were assessed for the collection of blood samples by jugular venipuncture at the following time points: immediately after birth, and before colostrum intake (first day of life is D1), and D2, D7, D14 and D28 days of life. Two hours prior to morning milk feed, calves were sampled, after being physically examined to establish reference values for heart rate (HR), respiratory rate (RR), and rectal temperature (RT). Several changes in physical, haematological, and biochemical parameters, secondary to neonatal adaptation, were detected. The reduction in HR and RR over time represented the maturation of the cardiovascular and respiratory systems, respectively, and the increase in RT represented the development of thermoregulatory mechanisms. Colostrum intake was reflected in several parameters, including immunoglobulin absorption and alteration of the serum protein profile. In addition, changes in glucose and cholesterol concentrations reflected the activation of the calf’s metabolism. Changes in white blood cell parameters, such as an increase in lymphocyte count and decrease in neutrophil count, were associated with maturation of the immune system and the influence of cortisol levels at parturition, respectively. Changes in the red blood cell count parameters could be attributed to the replacement of erythrocytes from the foetal circulation. Variations in the physiological parameters of calves were observed during the first month of life; it is necessary to compare them with established age-specific reference ranges for a better clinical interpretation.

Precise methods for measuring livestock body and carcass composition are essential for both animal and meat scientists. The aim of this study was to calibrate the 11th rib cut dissection method for the estimation of crossbred beef-on-dairy bull empty body (EB) and carcass compositions against reference tissue and chemical postmortem measurements. Sixty-six (66) crossbred bulls from Angus, Limousin and Simmental sires (n = 22 each) crossed on Brown Swiss dams were serially slaughtered along growth from 58 to 534 kg BW. The muscle, adipose tissue and bone contents of the left 11th rib were determined by physical dissection. Linear regressions followed by leave-one-out-cross-validation were tested between rib dissection variates (with or without additional ones: BW or carcass weight, carcass grading or postmortem linear measurements) and reference EB or carcass chemical (water, lipids, proteins, minerals and energy) and tissue (muscles, adipose tissues and bones, only for final slaughter group of 514 ± 12 kg BW, n = 30) compositions. When all bulls are considered (serial slaughter group, n = 66), the inclusion of rib dissection variate together with BW or hot carcass weight allowed precise estimations of EB and carcass masses and proportions of water [R² ≥ 0.91, residual CV (rCV) ≤ 3.1%], lipid (R² ≥ 0.88, rCV ≤ 14.0%), protein (R² ≥ 0.23, rCV ≤ 3.7%) and energy (R² ≥ 0.89, rCV ≤ 7.7%). Slight further improvements in precision were achieved when carcass grading conformation or fat scores was added to the multiple estimative regressions. Crossbreed effect was significant on the intercept of most of the predictive equations. Especially ×Angus had higher intercepts for lipids, energy and adipose tissues and lower ones for water, proteins and muscles, when compared to ×Limousin and ×Simmental. Further developments using for example rib imaging analysis rather than physical dissection may contribute to large scale and high-throughput phenotyping of body and carcass compositions.

Live weight (LW) is a key and conventional indicator for monitoring and assessing overall animal performance and welfare, representing the progress through different physiological stages, while providing close indication of individual physical and health status. Measuring LW in practice is still, however, quite rare and infrequent under commercial sheep farming conditions, mainly because sessions are time-consuming, stressful either for the operator or the animals. A Walk-over-Weighing (WoW) system was tested in this experiment lasting 14 weeks (i.e. 3 weeks for acclimation and adaptation and 11 weeks for data collection). We validated its use for routine and frequent monitoring of growth rate in postweaned Merinos d’Arles ewe lambs (n = 100), reared under Mediterranean grazing conditions. The necessity for an initial adaptation period of the animals was confirmed. Also, the importance of conducting an effective data cleaning procedure of the raw database automatically collected by the WoW was corroborated. Adaptation of naive ewe lambs enabled the required voluntary passages across the weighing platform and a high volume of individual and daily data after 2–3 weeks. Close monitoring of individual growth was then possible after performing sound data cleaning. A good agreement was demonstrated between WoW LW and a reference LW value (measured with a standard static scale). At the individual level, even with the lowest number of LW values collected with WoW, it was possible to monitor variations in LW at daily intervals. The establishment of an early warning system to help farmer decision-making could therefore be possible. Our results show interesting prospects for more accurate and frequent monitoring of LW in grazing sheep without human intervention, compared to what is currently carried out on commercial farms.

The possibility of pre-birth microbiota colonisation remains controversial in the scientific community. Due to the placenta’s characteristics in pigs, the umbilical cord is the sole way for mother-foetus microbial transmission to occur. Studies on this topic have demonstrated conflicting results; some of these discrepancies might be due to differences during sampling, DNA extraction, bioinformatics and data analysis. The aim of this study is to assess a workflow for characterising the umbilical cord blood microbial profile by adjusting for the contaminating sources of bacterial DNA during the extraction procedure. The results show that among 735 amplicon sequence variants (ASVs), 568 ASVs were contaminants, while 165 ASVs were true samples. Using this workflow, we could distinguish the contaminant ASVs introduced during bacterial DNA extraction and amplification. With the results of the present study, however, we cannot confirm the pre-birth bacterial transfer by the umbilical cord blood due to the lack of samples representative of the contaminants in the surrounding sampling environment. Nevertheless, the present study can be used as a reference to address low microbial biomass, particularly with umbilical cord blood.