Precision Feeding and Management of Farm Animals

The limitation on the prophylactic use of antibiotics in animal feed in Europe has critically challenged the rabbit meat industry, which urgently needs to find solutions. A feasible alternative could be using macroalgae in the diet to improve the gut health. This research studied seven species of marine macroalgae in four formats (dehydrated, enzymatically hydrolyzed, aqueous extract, and aqueous extract of hydrolyzed macroalgae) in order to select the most promising ones for their use in rabbit feed. Chemical composition, in vitro digestibility, in vitro caecal gas, total volatile fatty acid (VFA) production, and minimal inhibitory concentrations (MIC) against common pathogens were studied. All S. latissima products showed high caecal fermentability and VFA production, especially in both types of extracts. The H. elongata aqueous extract was remarkable due to its high in vitro butyrate production, which can be of great interest for improving gut health. The MIC results did not indicate any clear inhibition of the pathogens tested. The macroalgae tested appear to have a potentially prebiotic effect, rather than a direct antimicrobial activity. However, these results must be confirmed in vivo, in order to observe the real benefits of feeding macroalgae during the rabbit weaning period. Full article

The continued increase in milk production during the last century has not been accompanied by an adequate dry matter intake (DMI) by cows, which therefore experience a negative energy balance (NEB). NEB is low and of minor importance at low milk yield (MY), such as for the nutrition of one calf, and under these circumstances is considered “natural”. MY and low DMI around parturition are correlated and are the reason for the genetic correlation between increasing MY and increasing NEB up to 2000 MJ or more for 2–3 months postpartum in high-genetic-merit dairy cows. The extension and duration of NEB in high-producing cows cannot be judged as “natural” and are compensated by the mobilization of nutrients, particularly of fat. The released non-esterified fatty acids (NEFAs) overwhelm the metabolic capacity of the cow and lead to the ectopic deposition of NEFAs as triglycerides (TGs) in the liver. The subsequent lipidosis and the concomitant hampered liver functions cause subclinical and clinical ketosis, both of which are associated with “production diseases”, including oxidative and endoplasmatic stress, inflammation and immunosuppression. These metabolic alterations are regulated by homeorhesis, with the priority of the physiological function of milk production. The prioritization of one function, namely, milk yield, possibly results in restrictions in other physiological (health) functions under conditions of limited resources (NEB). The hormonal framework for this metabolic environment is the high concentration of growth hormone (GH), the low concentration of insulin in connection with GH-dependent insulin resistance and the low concentration of IGF-1, the so-called GH-IGF-1 axis. The fine tuning of the GH-IGF-1 axis is uncoupled because the expression of the growth hormone receptor (GHR-1A) in the liver is reduced with increasing MY. The uncoupled GH-IGF-1 axis is a serious impairment for the GH-dependent stimulation of gluconeogenesis in the liver with continued increased lipolysis in fat tissue. It facilitates the pathogenesis of lipidosis with ketosis and, secondarily, “production diseases”. Unfortunately, MY is still increasing at inadequate DMI with increasing NEB and elevated NEFA and beta–hydroxybutyric acid concentrations under conditions of low glucose, thereby adding health risks. The high incidences of diseases and of early culling and mortality in dairy cows are well documented and cause severe economic problems with a waste of resources and a challenge to the environment. Moreover, the growing public concerns about such production conditions in agriculture can no longer be ignored. Full article

The gastrointestinal tract (GIT) wet pool size (GITwps) refers to the total amount of wet contents in GIT, which in small ruminants can reach up to 19% of their body weight (BW). This study aimed to develop models to comprehensively predict GITwps in small ruminants using a meta-regression approach. A dataset was created based on 21 studies, comprising 750 individual records of sheep and goats. Various predictor variables, including BW, sex, breed, species, intake level, physiological states, stages and types of pregnancy, dry matter intake, and neutral detergent fiber intake (NDFI), were initially analyzed through simple linear regression. Subsequently, the variables were fitted using natural logarithm transformations, considering the random effect of the study and residual error, employing a supervised forward selection procedure. Overall, no significant relationship between GITwps and BW (p = 0.326) was observed for animals fed a milk-based diet. However, a strong negative linear relationship (p < 0.001) was found for animals on a solid diet, with the level of restriction influencing GITwps only at the intercept. Furthermore, the prediction of GITwps was independent of sex and influenced by species in cases where individuals were fed ad libitum. Pregnant females showed a noticeable reduction in GITwps, which was more pronounced in cases of multiple pregnancies, regardless of species (p < 0.01). The composition of the diet was found to be the primary factor affecting the modulation of GITwps, with NDFI able to override the species effect (p < 0.0001). Overall, this study sheds light on the factors influencing GITwps in small ruminants, providing valuable insights into their digestive processes and nutritional requirements. Full article

The objective of this study was to characterize foot angle and claw set scores of Montana’s (USA) registered Angus cattle using a total of 4723 cattle scored: 1475 yearling bulls, 992 yearling heifers, 1044 2- and 3-year-old cows, and 1212 cows ≥ 4 years old. Yearling bulls had a 0.12 and 0.20 greater mean foot angle and claw set score, respectively, compared to yearling heifers (p < 0.01). Foot angle and claw set scores increased (p < 0.01) with advancing cow age. The combined worst foot changed quadratically with age (p < 0.01) with the majority of problem feet in cows aged 2 to 3 years and older being hind feet issues. The proportion of foot angle and claw set scores not equal to 5 increased quadratically with age (p < 0.01), with heifers having the lowest proportion of scores not equal to 5 (15.8 and 31.7%, respectively) compared to cows aged 4 years and older. Sire lines had an effect on progeny claw set (p < 0.05) and foot angle scores (p < 0.05), as well as variation of progeny foot scores. These data could potentially be used to refine expected progeny difference models. Full article

The accurate identification of sheep is crucial for breeding, behavioral research, food quality tracking, and disease prevention on modern farms. As a result of the time-consuming, expensive, and unreliable problems of traditional sheep-identification methods, relevant studies have built sheep face recognition models to recognize sheep through facial images. However, the existing sheep face recognition models face problems such as high computational costs, large model sizes, and weak practicality. In response to the above issues, this study proposes a lightweight sheep face recognition model named LSR-YOLO. Specifically, the ShuffleNetv2 module and Ghost module were used to replace the feature extraction module in the backbone and neck of YOLOv5s to reduce floating-point operations per second (FLOPs) and parameters. In addition, the coordinated attention (CA) module was introduced into the backbone to suppress non-critical information and improve the feature extraction ability of the recognition model. We collected facial images of 63 small-tailed Han sheep to construct a sheep face dataset and further evaluate the proposed method. Compared to YOLOv5s, the FLOPs and parameters of LSR-YOLO decreased by 25.5% and 33.4%, respectively. LSR-YOLO achieved the best performance on the sheep face dataset, and the [email protected] reached 97.8% when the model size was only 9.5 MB. The experimental results show that LSR-YOLO has significant advantages in recognition accuracy and model size. Finally, we integrated LSR-YOLO into mobile devices and further developed a recognition system to achieve real-time recognition. The results show that LSR-YOLO is an effective method for identifying sheep. The method has high recognition accuracy and fast recognition speed, which gives it a high application value in mobile recognition and welfare breeding. Full article

Respiratory diseases commonly affect livestock species, negatively impacting animal’s productivity and welfare. The use of precision livestock farming (PLF) applied in respiratory disease detection has been developed for several species. The aim of this systematic review was to evaluate if PLF technologies can reliably monitor clinical signs or detect cases of respiratory diseases. A technology was considered reliable if high performance was achieved (sensitivity > 90% and specificity or precision > 90%) under field conditions and using a reliable reference test. Risk of bias was assessed, and only technologies tested in studies with low risk of bias were considered reliable. From 23 studies included—swine (13), poultry (6), and bovine (4) —only three complied with our reliability criteria; however, two of these were considered to have a high risk of bias. Thus, only one swine technology fully fit our criteria. Future studies should include field tests and use previously validated reference tests to assess technology’s performance. In conclusion, relying completely on PLF for monitoring respiratory diseases is still a challenge, though several technologies are promising, having high performance in field tests. Full article

The leaf extracts of Dacryodes edulis possess high concentrations of alkaloids, saponins, flavonoids, and tannins with various biological activities, including antimicrobial, antifungal, and antioxidant activities. These activities can be used in animal production to avoid the energy lost in favor of growth and reproduction. A total of 48 Brahma hens (45 days old), weighing on average 400 ± 12 g, were randomly distributed into four dietary treatment groups (12 birds each) with four replicates per group. The control group (T0) received 0% D. edulis, while the three test groups (T0.25, T0.50, and T0.75) were given feed with D. edulis powder leaves at concentrations of 0.25, 0.5, and 0.75%, respectively, for a period of 60 days. Water and feed were supplied ad libitum. At the end of the study period (60 days), eight birds per treatment (two per replicate) were fasted, weighed, and slaughtered. Blood samples and organs were collected for analysis of growth characteristics, oxidative stress, and toxicity indices. This study revealed a significant (p < 0.05) increase in feed intake and live body weight with 0.75% D. edilus powder leaves. Abdominal fat was found to be significantly (p < 0.05) lower with 0.75% D. edilus powder leaves compared to the control group. Serum Aspartate aminotransferase activity was significantly (p < 0.05) lower in birds exposed to 0.75% D. edulis leaf powder compared to the control group. The use of D. edulis leaf powder as feed additive in feed could reduce oxidative stress and improve growth performance in Brahma. More research can be conducted on D. edilus, and it can be used in broiler feed at 0.75% concentration, which has shown a significant increase and decrease, respectively, in live body weight and serum aspartate aminotransferase activity. Full article

To determine the optimal timing for performing castration on goats, eighteen male Nubian crossbred goats were randomly assigned to two groups and castrated at 3 months and 6 months of age, respectively. Daily dry matter intake, biweekly body weights, and ultrasonic measurements of longissimus dorsi muscle growth were recorded. Results indicated that there was no significant difference between the two groups in terms of the blood parameter analysis (except testosterone, 0.36 ± 0.26 vs. 3.61 ± 0.27 ng/mL at 25 weeks old), economic analysis, and growth performance, including final body weight, total weight gain, average daily gain, total dry-matter intake, and feed conversion ratio (p > 0.05). However, the longissimus dorsi muscle depth of goats castrated at 6 months of age was significantly higher than that of goats castrated at 3 months of age. In conclusion, castration timing does not have a significant effect on the growth performance of goats; therefore, castrating goats at 3 months of age may be the best practice considering animal welfare and possible risks associated with late castration. Full article

Angus and Red Angus-based yearling heifers (n = 40) and lactating cows (n = 51) were each used in a complete randomized design and stratified by weight and body condition score to one of two treatments: (1) pressed supplement block containing rumen undegradable protein (RUP) and (2) pressed supplement block containing rumen degradable protein (RDP). Heifer and cow supplement intake displayed (p < 0.01) a treatment × period interaction. The RUP heifers and RDP cows consumed more in Period 2 than Period 1, whereas RDP heifers and RUP cows consumed more in Period 1 than Period 2, respectively. Intake rate demonstrated (p < 0.01) a treatment effect for heifers, with RUP consuming supplement faster than the RDP treatment. Intake rate for cows demonstrated (p < 0.01) a treatment × period interaction with RUP cows in Period 1 having faster intakes than Period 2, and RDP cows having the inverse. Cow intake variation displayed (p < 0.01) a treatment × period interaction with RUP cows having more variation in Period 2, while RDP cows had less variation in intake in Period 2. In conclusion, RDP and RUP impacted intake behavior of cows and heifers but had minimal impacts on performance. Full article

In order to solve the problems of poor feeding environment, untimely feeding and high labor demand in poultry smart farms, the development of feeding robots is imminent, while the research on path planning algorithms is an important part of developing feeding robots. The energy consumption of the feeding robot is one of the important elements of concern in the process of path planning. In this study, the shortest path does not mean that the feeding robot consumes the least energy, because the total mass of the feeding robot keeps changing during the feeding process. It is necessary to find the most suitable path so that the feeding robot consumes the lowest amount of energy during the feeding process. A branch and bound algorithm to calculate the minimum energy consumption travel path for small-scale buckets lacking feed is proposed. The lower bound of the branch and bound on the energy consumption is obtained by the approach of preferred selection of the set of shortest edges combined with the sequence inequality, and the upper bound could be obtained based on Christofides’s Heuristic algorithm. A double-crossover operator genetic algorithm based on an upper bound on energy consumption for large-scale buckets lacking feed is proposed, and different crossover operations are performed according to the relationship between the fitness value and the upper bound of energy consumption in order to find a better path. The experiment results show that the approach proposed in this study is efficient; for small-scale buckets lacking feed, a branch and bound algorithm could calculate the minimum energy consumption path of 17 points in 300 s, and for large-scale buckets lacking feed, a double-crossover operator genetic algorithm based on an upper bound on energy consumption could calculate the minimum energy consumption travel path within 30 points in 60 s. The result is more accurate compared to the genetic algorithm with a single crossover operator. Full article

Residual feed intake (RFI) is the preferred measurement for feed efficiency in beef cattle, but it is laborious to determine. Data from two experiments of growing bulls (test period durations of 56 and 63 days) were used to examine how a reduction in the number of times the animals were weighed and the shortening of the length of the observation period affect the reliability of the RFI determination. We introduce two easily understandable probability measures for assessing reliability. ‘The consistency of the pair-wise ranks’ gives the probability that the rank of any two animals compared remains the same when the amount of data is reduced. ‘The consistency of the thirds’ gives the probabilities that an individual animal will remain in the same, i.e., the lowest, middle, or highest, third of animals. The reliability of the results was not greatly affected when the weighing interval was reduced from one week to four weeks. However, shortening the test period resulted in a marked reduction in the reliability of RFI. If individual feed intake is automatically measured, the workload required for RFI measurements can most effectively be reduced by reducing the number of weighing times but keeping the duration of the test period long enough. Full article

In view of the low accuracy and slow speed of goat-face recognition in real breeding environments, dairy goats were taken as the research objects, and video frames were used as the data sources. An improved YOLOv4 goat-face-recognition model was proposed to improve the detection accuracy; the original backbone network was replaced by a lightweight GhostNet feature extraction network. The pyramid network of the model was improved to a channel management mechanism with a spatial pyramid structure. The path aggregation network of the model was improved into a fusion network with residual structure in the form of double parameters, in order to improve the model’s ability to detect fine-grained features and distinguish differences between similar faces. The transfer learning pre-training weight loading method was adopted, and the detection speed, the model weight, and the mean average precision (mAP) were used as the main evaluation indicators of the network model. A total of 2522 images from 30 dairy goats were augmented, and the training set, validation set, and test set were divided according to 7:1:2. The test results of the improved YOLOv4 model showed that the mAP reached 96.7%, and the average frame rate reached 28 frames/s in the frontal face detection. Compared with the traditional YOLOv4, the mAP improved by 2.1%, and the average frame rate improved by 2 frames/s. The new model can effectively extract the facial features of dairy goats, which improves the detection accuracy and speed. In terms of profile face detection, the average detection accuracy of the improved YOLOv4 goat-face-recognition network can reach 78%. Compared with the traditional YOLOv4 model, the mAP increased by 7%, which effectively demonstrated the improved profile recognition accuracy of the model. In addition, the improved model is conducive to improving the recognition accuracy of the facial poses of goats from different angles, and provides a technical basis and reference for establishing a goat-face-recognition model in complex situations. Full article

Epidemic disease prevention plays a critical role in ensuring the healthy development of livestock farming, and the subjective willingness of breeders can be affected by the cost of epidemic disease prevention. To correct the misconception that farmers regard the cost of disease control as an ineffective cost, and to promote the healthy development of the pig breeding industry, our study employed the data envelopment analysis super-efficiency model and panel threshold regression model to evaluate the combination of the cost of epidemic disease prevention and swine productivity using data collected from 1998–2018 across 30 provinces in China. The following results were obtained. (1) The cost of epidemic disease prevention generated a non-linear on swine productivity when the swine farming scale was limited; (2) When the number of animals at the beginning of the year was less than 6.0002, swine productivity was impacted negatively; (3) When the number of animals at the beginning of the year ranged between 6.0002 and 12.9994, the impact was insignificant; (4) A strong correlation was observed between the expenses of epidemic disease prevention and animal productivity when the number of animals at the beginning of the year exceeded 12.9994. These results indicate that publicity should be enhanced to elucidate the combination of epidemic disease prevention and swine productivity among breeders. In addition, the government should introduce relevant policies to encourage the development of large-scale pig farming, such as subsidies for the construction of large-scale farms and insurance. Full article

Adaptivity of eating and rumination behavior are assumed to play a particular role for cows in low-input systems, because they are more frequently challenged by altering forage quality. The present study examined relations between forage quality, chewing behavior and efficiency estimates in dairy cows from Swiss zero-concentrate organic farming systems. A total of 102 Swiss Fleckvieh cows on two organic dairy farms were observed during one full production year. Each farm was visited eight times. At each visit, up to 45 cows were equipped with RumiWatch^® (Itin and Hoch GmbH, Liestal, Switzerland) sensor head collars, from which eating and rumination time and the frequency of activity changes were obtained for 48 h. Milk from one complete day was analyzed individually. All offered roughages (pasture herbage, grass silages and hay) were sampled at each visit and analyzed for crude fiber, crude protein and net energy, and a feed quality score was calculated. Metabolic production efficiency was estimated based on entire lactation data, and feed efficiency was estimated based on the individual farm visits. Lactation stage and forage quality significantly affected the chewing sensor variables. Eating time increased and rumination time decreased with the improved nutritive quality of feed. Coefficients of variance of the factor animal in the sensor variables showed a contribution of the individual cow to chewing behavior. Significant correlations between chewing sensor variables and efficiency estimates were not found. In conclusion, chewing behavior under on-farm conditions in low-input dairy farms alters during lactation and during changing forage quality, with significant animal effects, indicating potential for new phenotypes, albeit with no indications for efficiency. Full article

The rabbit meat industry has faced critical challenges in the last few years, during which the ban on the prophylactic use of antibiotics in animal feed has added to the weakness of the production system and a decrease in consumption of rabbit meat. This review paper highlights the potential value of macroalgae in the rabbit farming sector as an alternative to the use of antibiotics to improve rabbit health. In line with sustainable agriculture programmes, the use of seaweed in rabbit nutrition may improve gut health according to the One Health approach, whereby consumers and the environment could receive tangible benefits. The inclusion of algae in animal feed has experimentally proven to help to reduce intestinal dysbiosis. However, further studies evaluating the prebiotic effects of algal components on gut health and also identifying the compounds directly responsible for the antimicrobial, antiviral, antioxidative and anti-inflammatory properties of algae are still needed. Furthermore, the inclusion of marine algae in rabbit food could potentially become a commercial marketing strategy that could attract new consumers who are concerned about environmental sustainability and who are looking for different, high-quality foods. Full article

This technical report used a wireless device (CURO MkII) that recorded high-quality rumen sound waves from cows of different production statuses (dry cow vs. lactating cow) and physiological stages (pregnant vs. non-pregnant). Recordings from a dry Jersey heifer fed a diet based on haylage and straw showed a few high-amplitude spikes (3 at 6 dB) but mostly infrequent signals (9 at 12 dB and 22 at 18 dB), with pauses of approx. 2 min with no rumen sounds in between. Analysis of a few individual spikes in the 12 dB range showed that wave frequencies ranged from 230 to 250 Hz and lasted 4 s. Recordings of the high-yielding Red Danish cow fed a total mixed ration (TMR) showed an almost constant frequency of the rumen sounds with considerable amplitude of the waves. Rumen sounds from the Red Danish dry and pregnant cow fed on TMR were less frequent, with a lower amplitude than those from the high-yielding cow. These preliminary results demonstrate that wireless sound recording units are capable of measuring rumen sounds in a production setting and can discern between animals of different production and physiological stages, but more studies are needed to confirm our findings. Full article

Instability in grain prices led to continuing worldwide growth in the proportion of fat supplements in lactating cows’ rations. However, fat supplementation was associated with decreases in feed intake, rumen fermentation, and feed digestibility. The present objectives were to test the effects of high-fat diets from calcium salts of palm oil fatty acids (CS-PFA) in lactating cow rations containing high proportions of concentrate, on feed intake, milk yields, rumen environment, and digestibility. Forty-two multiparous mid-lactation dairy cows were assigned to three treatments, designated as low fat (LF), moderate fat (MF), and high fat (HF) that contained (on DM basis), respectively, (i) 4.7% total fat with 1.7% CS-PFA, (ii) 5.8% total fat with 2.8% CS-PFA, and (iii) 6.8% total fat with 3.9% CS-PFA. Rumen samples were collected for pH, ammonia, and volatile fatty acid (VFA) measurements, and fecal grab samples were collected for digestibility measurements. A numerical trend of decreasing dry matter intake with increasing CS-PFA in diet was observed: 28.7, 28.5, and 28.1 kg/day in LF, MF, and HF, respectively (p < 0.20). No differences between treatments were observed in milk yields and milk-fat percentages, but protein percentage in milk tended to fall with increasing dietary CS-PFA content (p < 0.08), which resulted in 6.4% smaller protein yields in the HF than in the LF group (p < 0.01). Milk urea nitrogen was 15.3% higher in HF than in LF cows (p < 0.05). Rumen pH was higher at all sampling times in the MF and HF than in the LF cows. Concentrations of propionic acid and total VFA were higher in LF than in MF and HF cows. The apparent total-tract digestibility of dry matter was higher with LF than with HF (p < 0.002), and that of organic matter was lowest with the HF diet (p < 0.005). The apparent NDF digestibility declined with increasing dietary fat content, and it was 8.5 percentage points lower in HF than in LF cows (p < 0.009). Apparent fat digestibility increased with increasing dietary fat content, and it was higher by 10.4 percentage points in the HF than in the LF group (p < 0.004). In conclusion, diets with high concentrate-to-forage ratios, containing up to 6.8% total fat and 3.9% CS-PFA, negatively affected rumen fermentation and NDF digestibility in high-yielding dairy cows; however, the effects on yields were minor, indicating that, under specific circumstances, the inclusion of large amounts of CS-PFA in dairy cows’ rations with low fiber content is feasible. Full article