Animal - Open Space最新文献

The aim of this study was to investigate the effects of gradually increased dietary CP level on the dynamics of individual egg production of laying hens from 18 to 54 weeks of age. Forty Hy-Line Brown hens were divided into five treatments of eight replicates each and were fed diets formulated to have five different CP concentrations: 14, 15, 16, 17, and 18% CP with the same energy content. For each experimental diet, the contents of lysine, methionine + cysteine, threonine, and tryptophan were maintained at minimum requirement concentrations by supplying synthetic amino acids. Clutch characteristics were recorded (e.g., number, size, patterns, egg weight, etc.) and individual egg production curves were modeled according to Grossman and Koops (2001). Clutch size was defined as the unstopped length of individual egg production on a daily basis. BWs were also recorded every week to account for changes in BW during the experimental period. Three hens were excluded from the statistical analyses as their laying patterns were very inconsistent. Four clutch patterns with data weighted on a weekly basis were identified. Heavier hens tended to lay more regular clutch patterns when compared to their lighter counterparts within the same treatment. In contrast, irregular clutch patterns (too many pauses between clutches) were more common in hens fed low CP diets (≤16%). This could be explained by imbalances in amino acids supply according to their theoretical requirements and adverse effects caused by amino acids interactions. Low CP diets were able to maintain egg production and mean clutch size up to 54 weeks of age. The maximum clutch size and the modeled proportion of maximum production for the increasing phase (k₁) displayed a linear response to the graded addition of CP content to the diet. No differences were detected among treatments for the age at the beginning of the maximum clutch (22.6 ± 2.82 weeks). Egg weight displayed a quadratic response that was maximized when hens were fed 17% CP in the diet. Our approach appears to be promising for ranking individual laying hens based on their clutch performance to evaluate both CP and amino acids adequacy of diets.

Antimicrobial growth promoters (AGPs) have been banned from animal husbandry owing to their association with the occurrence of bacterial resistance. Although the mechanism of action of AGP is still unknown, it is believed to be related to an anti-inflammatory action in the gastrointestinal tract. In this context, the aim of the present study was to establish if supplementation of broiler feed with the non-steroidal anti-inflammatory sodium salicylate (SS) induces adverse effects related to this class of drug and to evaluate the potentiality of SS in improving the zootechnical indices of broilers. One-day-old Cobb 500 male chicks were divided into four groups (12 per group) and treated over a period of 42 days with non-supplemented feed (control group) or with feed to which doses of 2.5, 5.0, or 10.0 mg of SS/kg BW were added daily. Feed intake and BW were assessed and haematological, biochemical, and histopathological alterations were evaluated throughout the experiment. Whereas no statistical differences in food intake or BW were detected between the groups, a 5.8% increase in total BW gain was observed in broilers treated with 10 mg of SS/kg BW. In addition, the highest dose of SS studied generated the lowest total feed conversion rate over the experimental period in comparison with all other SS treatment groups. Haematological and biochemical evaluations did not reveal any altered parameters that could be related to the adverse effects of SS. No renal or hepatic alterations were detected in the histopathological study of tissue collected on day 42, and no lesions or ulcerations were observed in the gastrointestinal tract. We conclude that daily doses of SS in the range of 2.5–10 mg/kg BW can be added safely to broiler feed for 42 days, and that this non-steroidal anti-inflammatory drug is promising for future studies of its use as a growth-promoting agent.

Irregular milking intervals in automated milking systems contribute to additional variation in daily milk yield records in comparison to those derived from systems using regular milking intervals. Various methods have been developed to estimate 24-h adjusted milk yields, though they are not well suited for the evaluation of serial milk yield data, particularly when milking intervals span calendar days. The objective of this study was to develop a methodology to estimate serial 24-h milk yields by adjusting for irregular milking intervals. Using data collected from an automated milking system (AMS), the total yield at a given milking event and the elapsed time from the previous entry into the AMS were used to calculate the milking interval and the average rate of milk secretion over that interval. Milking intervals and associated milk secretion rates were then realigned to calendar days to allow the proportional distribution of milk yield when milking intervals spanned more than one day. Using this method, variation in daily milk yield was decreased and adjusted estimates of 24-h milk yield were visually more similar to those typically observed in milking systems with regular milking intervals. Estimates of interval-adjusted milk yields were strongly correlated to those calculated using moving averages, suggesting that this method can yield comparable results to established methods for estimation of test-day milk yield.

The increasing breast weight of modern broilers highlights the convenience of studying the dynamics of processing weights across the grow-out period. For models predicting these traits to work with non-fasted live birds under longitudinal studies, it is necessary to determine the changes in the weights of birds due to fasting and bleeding and carcasses due to chilling. This study aimed to develop a model to predict the fasting weight loss of broilers, determine the weight changes due to bleeding and chilling, and assess the percentage of gizzard fat in the abdominal fat. Models were fitted to fasting BW loss data from literature. A bleeding BW loss value obtained in a pilot study was compared to literature. This one and a single-source percent gizzard in the abdominal fat value were used as reference values. Birds from two experiments were selected at different ages to determine the following variables: non-fasted and fasted BW, bled weight, unchilled and chilled carcass weights, and gizzard fat and abdominal fat pad weights. Predicted and reference values were compared to the observed data based on their 95% confidence intervals, and the fitted model and reference values were validated if no statistical differences were inferred. The fasting BW loss model was refitted to the data from experiments, and the estimates of the model fitted to both datasets were compared. The fasting BW loss followed a three-parameter exponential model with reducing values as the bird aged, and the predicted and observed values showed no statistical difference (P > 0.05). The reference bleeding BW loss (2.76%) and gizzard fat percentage (18%) values showed no difference (P > 0.05) to data from broiler experiments, and a chilling carcass weight gain of 2.79% was determined. The scale and relative growth rate estimates of the fasting BW loss model showed no difference (P > 0.05) between datasets, and the asymptote showed a possible but negligible difference. The fasting BW loss model, the bleeding BW loss coefficient, and the gizzard fat percentage were validated. The model and coefficients obtained herein will not only be applied to predict processing weights using Dual-Energy X-ray Absorptiometry but also may be used in other modeling approaches.

Animal welfare in the European Union is strictly regulated and has the highest standards in the field. It is also present in the CAP in both the first and second pillars. In Sardinia, animal welfare has taken on greater importance since it was introduced via the Rural Development Plan (RDP) in 2005. The context in which the animal welfare programme was initiated was that of a rural setting that had never before followed such projects and to which even the word welfare aimed at animals was alien. The welfare plan was geared hygiene in milking and housing, and the fight against foot problems and stress for primiparous ewes during the first week of milking. After 15 years of implementing animal welfare support interventions from public funds, this work aimed to investigate the perception of animal welfare among both beneficiary farmers and citizen-consumers. The data were collected in a linked survey on both farmers and consumers who are involved in the profound social and economic implications for the Island. On the one hand, 98% of breeders consider animal welfare to be important for the health and productivity of their animals, even though 59% also claim to have changed little or nothing in their farm management following the introduction of RDP measures, partially because the animal welfare measures were already being practised. On the other hand, public respondents’ willingness to pay more when it comes to purchase decisions can be considered as interesting evidence of a possible collective understanding which deserves further investigation. The results highlight the fact that animal welfare is undoubtedly a well-known and topical issue which has gained widespread attention and a broad agreement on its relevance and priority. Nonetheless, a shared vision on the meaning of welfare is lacking, even within regional policies that appear to be strongly segmented.

The efficiency of replacement programmes in dairy farms depends largely on the heifers’ growth rate. We provide a case study of control chart application to monitor the weight of dairy replacement heifers. A research dairy farm in Córdoba province, Argentina, provided the monthly samples of BW measurements of 2, 9, and 14.5-month-old heifers born between 2017 and 2019. The data were used to build control charts for the mean and for SD, with moving range control limits in order to consider varying sample sizes. In each age group, control charts for the mean showed at least one out-of-control sample, whereas control charts for SD showed one sample out of control for 9-month-old heifers. Each sample outside the control limits implies that a potentially identifiable cause has occurred. Therefore, the producer could identify the event causing the deviation and make the necessary changes according to the heifer’s age. Control charts provide the producer and consultant with graphical information and quick alerts to support the decision-making process of the replacement programme. These tools are useful at the farm level to monitor heifer weights and support management decisions.

The production of methane by the rumen microbiota is a complex biological process. When tackling the modelling of methane production, the modeller decides what complexity is needed to answer the scientific question for which the model is intended. Such a choice results in a diversity of possible models spanning both empirical and mechanistic approaches. Within the framework of precision livestock farming, simple dynamic models offer great advantages for integrating online data (e.g., feed intake) to predict individual methane emissions from cattle. Accordingly, we previously developed, with satisfactory results, a simple dynamic model that uses DM intake kinetics as a single predictor of methane emissions from finishing beef steers. The objective of the present work was to assess the capability of the previously developed model to predict the dynamic pattern of methane production from dairy cows fed a diet containing either wheat grain or corn grain. We showed that the simple dynamic model in its original form enables a description of the dynamics of individual methane emissions from dairy cows with an average determination coefficient (r²) of 0.65 and an average concordance correlation coefficient of 0.81 and RMSE of 16% and 26% for the corn-based and wheat-based diets, respectively. Additionally, we performed a principal component analysis associating the parameters of the methane model with variables characterising the feeding behaviour of the cows. The results showed the effect of the diet type on the feeding behaviour of the animals. This impact was propagated on the dynamics of methane emissions. Interestingly, our model enabled us to determine that the differences in patterns of methane emissions between the diets result simply from the dependency of the methane yield and rate constant of methane eructation on the grain type.

A considerable opportunity exists in evaluating the dynamics of the carcass and the processing cut-up weights of broilers across the whole grow-out period as influenced by intervention factors. However, no fast and objective tool exists up to date to make such determinations. This study aimed to develop models to predict the unchilled and chilled weights of the carcass and cut-up pieces of broilers using Dual-Energy X-ray Absorptiometry (DEXA) and feathered non-fasted birds. Highly diverse (BW and body composition) broilers (n = 291) between 4 and 79 days of age were euthanized, DEXA-scanned, and manually processed to determine the weights of the carcass and cut-up pieces. Correction factors were applied to obtain the fasted BW and the corresponding bled and chilled weights. A database was built up, including all the weights recorded and the DEXA-reported indexes. A stratified random data-splitting with a refitting approach was applied. Multiple least-squares linear regressions were fitted for each unchilled and chilled variable on the training dataset using JMP Pro 16. Natural log and square root transformations were applied to predictor variables as convenient, and outliers were removed. Candidate models were screened for normal distribution and homoscedasticity of residuals and collinearity among predictors. The highest precision (adjusted R²) and the lowest error (RMSE) were selection criteria. Once model overfitting and prediction performance was tested on the validation dataset, the models were refitted with all the data in the original dataset. Prediction models with high (unchilled and chilled carcass and cut-up weights, feet, and head; R² > 0.99) and acceptable (abdominal fat; R² > 0.69) precision were obtained. In conclusion, these results support the use of DEXA to determine the processing weights of broilers. Its application to the study of growth curves of cut-up pieces as influenced by nutrition, genetics, environment, and management opens a new spectrum of opportunities for the industry.

We collected data on the behaviour of dairy cows in barns, clinical signs of diseases as well as events that may stress or agitate the cows. A Real-Time Locating System gives the position of individual cows every second. The position of the cow is determined by triangulation based on radio waves emitted by a tag fixed on each cow neck collar and captured by antennas in the barn. The cow’s activity is inferred from its position: ‘eating’ if the cow is positioned at the feeding table, ‘resting’ if the cow is in a resting area (typically cubicles), else ‘in alleys’. We aggregated this information to get the time spent in each activity per hour. We also calculated the activity level of the cow for each hour of the day by attributing a weight to the time spent in each activity. For each cow and day, we collected information on health events or other events that may affect behaviour. There were 11 types of events. Six events were linked to health: lameness; mastitis; LPS (i.e. administration of lipopolysaccharide (LPS) in the mammary gland, an experimental treatment to induce udder inflammation); subacute ruminal acidosis; other diseases (such as colic, diarrhoea, ketosis, milk fever or other infectious diseases); and accidents (such as retained placenta or vaginal laceration). Two events were linked to reproduction: oestrus and calving. Three events were stress events: animal mixing, disturbance (i.e. mild intervention on animals such as late feeding, alarm test) and marginal management changes (ration changes, fill bed). In addition, a Boolean sums up whether this hour was considered as normal or not. Data contain four datasets. It consists of univariate time series. Each time series corresponds to the hourly activity level of a cow. Datasets 1 and 2 are from the INRAE Herbipôle experimental farm and include data from experiments; datasets 3 and 4 are from commercial farms. They contain data on respectively 28, 28, 30 and 300 cows monitored for 6 months, 2 months, 40 days and one year. The data can be used to study the links between health, reproduction events and stress on the one hand and cow behaviour on the other hand. More specifically, it can be used to build and test tools for an earlier detection of health and disturbances, with a view to inform caretakers so that corrective actions can be rapidly put in place.

In the present case study, the welfare of local breed (Krškopolje pig) pigs reared indoors, outdoors, and in combined production systems (total of 10 farms) were evaluated. The multidimensional Welfare Quality® assessment protocol, with slight modifications, was used to evaluate the farms. Animal-based observations were used to examine the four main principles of welfare (good feeding, good housing, good health, and appropriate behaviour) and their twelve independent welfare sub-criteria. Scores for each criterion were calculated and each farm was classified into one of the four welfare categories (excellent, enhanced, acceptable, or not classified). Maximal total scores were determined for the “good feeding” principle in the indoor and combined systems, whereas the outdoor system had a lower score (64) because of insufficient water troughs. In the case of “good housing” principle, maximal total scores were attributed to outdoor system, and lower scores for indoor and combined systems (72 and 84, respectively) due to the lesser space allowance, dirtiness and shivering in pigs. The scores for the “principle of good health” were rather low in all husbandry systems (62, 58, 61 for outdoor, indoor and combined systems, respectively), mainly because of the castration method practised without pain relief medication. The integrated score for “appropriate behaviour” was lower in indoor systems, because of lower “exploratory behaviour” scores (64). Considering the overall assessment across all principles, farms having only outdoor or only indoor system were classified as “enhanced” (total score of 77 and 74, respectively), whereas farms with combined system (indoor housing with outdoor access) were classified as “excellent” (total score of 85). The present study showed high welfare quality of housing systems with local breed Krškopolje pigs.