Animal - Open Space最新文献

This study compared two collection methods (CMs) to obtain ileal content from broiler chickens to determine apparent ileal amino acid digestibility coefficients (AIAAD). CM1 consisted of collecting the digesta by gently squeezing the ileum, while in CM2, the ileal digesta was flushed with distilled water. A total of 130 one-day-old male chicks were randomly distributed among 10 cages, using five replicate cages per CM. Birds were fed ad libitum with a standard starter diet from 0 to 18 d of age. At 18d, the diet switched to a corn-based semi-purified diet with 0.5% titanium dioxide (TiO2) as the indigestible marker. At 21d, birds were euthanized, and ileal digesta was collected using one of the two CMs. Bird performance was monitored; feed and lyophilized ileum content samples were analyzed to determine amino acids (AAs) and Ti content to determine AIAAD. A two-sided T-test and an F-test two-sided were performed to determine differences among the CMs’ means and variances, respectively. All significant differences were considered at a P-value < 0.05. Bird performance was similar for both groups throughout the experiment (P > 0.05). No significant differences between CMs were observed in the AIAAD coefficients for any of the amino acids analyzed (P < 0.05). The variances were significantly different for 6 AA (Iso, Lys, Thr, Ala, Asp, Glu; P < 0.05). In addition, four AAs approach significance (Leu, Met, Val, Pro; P < 0.1). The numeric values of the AAs variances were consistently higher when the sample was obtained using CM1. Squeezing may increase variability by enhancing endogenous losses like sloughed cells and mucin, underestimating digestibility in some samples. Using CM2 (flushing with distilled water) would provide more consistent and uniform results. This approach not only diminishes the likelihood of errors but also contributes to the standardization of methodologies applied in digestibility trials within the poultry research field.

The infection of the endophytic fungus (Epichloë festucae var. lolii) within perennial ryegrass (Lolium perenne) pastures can produce toxic alkaloids, including lolitrem B and ergovaline which can negatively impact animal welfare and behaviour through causing ryegrass staggers as well as poor growth and increased sensitivity to heat stress. Wearable 3-axis acceleration sensors can provide an alternative to automatically monitor individual grazing livestock who need essential treatment to minimise the impact of grazing pastures infected with an endophyte. The objective of this study was to categorise changes in ruminating, eating and other behavioural activities of grazing lambs exposed to endophyte-infected perennial ryegrass via commercial accelerometer sensors. Lambs were fitted with the ear-mounted accelerometer sensors (CowManager SensOors, Agis, Harmelen, the Netherlands) and allocated randomly within live-weight strata to graze either endophyte-free (Control) or wild−type endophyte-infected (Endophyte) perennial ryegrass pasture. Live weight change, behaviour and incidence of staggers were monitored over a 2-month grazing period. Moderately severe staggers (score 4/5) occurred in 40% of lambs in the Endophyte treatment with a mean staggers score of 2.33 ± 0.41 across the group. Compared with control lambs, endophyte-infected lambs compensated for reduced eating (−36.0 min/day) and inactive (−43.7 min/day) duration in favour of increased ruminating (+40.2 min/day) and active (+29.9 min/day) duration. The sensors also identified diurnal adaptations in behaviour of lambs which were affected by endophyte staggers, presenting significant effects of endophyte challenge by hour interaction on the diurnal eating duration (P < 0.001), diurnal ruminating duration (P < 0.001), diurnal inactive duration (P < 0.001), diurnal active duration (P < 0.001) and diurnal highly active duration (P < 0.001). In conclusion, these sensors were able to detect subtle changes in the behaviour of grazing sheep that can be used to detect subclinical symptoms of ryegrass staggers when consuming ryegrass staggers.

This study investigated the impact of the age at which heifers conceive for the first time on the growth and reproductive development of their female offspring. A total of seven heifers pregnant at 15 months of age (15M), nine heifers pregnant at 27 months of age (27M) and seven multiparous pregnant cows (Adult) were used in the present trial. All dams were pregnant by AI from a single sire and managed in a single group during gestation, lactation and rearing stages. After weaning heifer calves were stocked on natural pastures. Progeny of heifers that gestated for the first time at different ages did not present differences in growth; however, progeny of 15 and 27M dams had reduced BW, longissimus muscle area and 12th fat thickness compared to progeny of adult dams (P < 0.05). Diameter of the largest follicle was greater in progeny born to Adult compared to progeny born to 15 and 27M (P = 0.04). Reproductive tract score (RTS) in heifers born to Adult at 399 days of age was greater compared to heifers born to 27M, and this category presented greater development than heifers born to 15M (P = 0.02). At 435 days of age, the heifers born to Adult had a greater percentage defined as pubertal compared to the progeny of 15 and 27M (P = 0.04). At 495 days of age, the weight of uterus, ovaries and corpora lutea were not affected by the age of dams at calving (P > 0.25). These data indicated that the age at which heifers received their first service affects female offspring growth RTS at early ages, but it does not have any impact in organ development after diet with a high energy level.

Considering the potential environmental impact of livestock production and the significance of accurate estimation methods, it is crucial to assess the differences between various methodologies. The study compared the gross energy intake (GEI) and enteric methane (CH₄) emission factors (EF = kg CH₄/head/year) of cattle based on three methodologies: Intergovernmental Panel on Climate Change (IPCC) Tier 1, IPCC Tier 2 and a modified Tier 2 methodology based on Commonwealth Scientific and Industrial Research Organization (‘CSIRO’) Tier 2. Data were collected from smallholder mixed crop-livestock systems in the upper highland sub-humid to semi-humid (AEZ-1) and lower highland sub-humid to semi-humid (AEZ-2) zones of North Shewa, Ethiopia, corresponding to the beginning and end of spring, summer, and winter. The results revealed that the IPCC Tier 2 methodology estimated a 39% higher GEI (104 vs 74 MJ/ head^/day) and a 51% higher implied EF (50 vs 33 kg CH₄ /head/year) compared to the ‘CSIRO’ Tier 2 methodology. When compared to the IPCC Tier 1 default values, both the IPCC and ‘CSIRO’ Tier 2 EF estimates were 20–37% and 37–59% lower, respectively. Furthermore, all cattle categories exhibited variations in implied daily CH₄ production across seasons. As all the GEI were estimated, it is not possible to determine which methodology is more accurate. Therefore, future research should compare predicted intakes and emissions with actual experimental data to ascertain the accuracy of the models.

The objective of the current trial was to evaluate the effect of feeding four different forage species on milk yield and composition, including protein and fatty acid profiles, in dairy goats. Two grasses (Timothy; mown at early heading, and Italian ryegrass; mown at 25 cm height) and two legumes (Alfalfa and White clover; both mown at 10% bloom) were harvested and conserved as silage. Twelve dairy goats of three different breeds (4 Alpine, 4 Toggenburg, and 4 Saanen) in late lactation were used in a replicated 4 × 4 Latin square design. Goats were offered ad libitum access to the tested forages supplemented with 180 g/d of concentrates based on rolled barley and heat-treated soybean meal. DM intake was lower with timothy, intermediate with ryegrass and white clover, and greater with alfalfa. Milk yield was lower with timothy as compared with the other three silages. Milk fat yield was similar among treatments. Milk CP yield was lower with timothy as compared with the other three silages. Milk N efficiency (N secreted/N intake) was greater with timothy, intermediate with ryegrass, and lower with the two legume silages. The proportion of true protein as a percentage of CP was lower in milk from goats fed legume as compared with grass silages. Proportions of casein and whey protein expressed as percentages of true protein were greater with timothy, intermediate with ryegrass and white clover, and lower with alfalfa. Among grass silages, intake and milk secretion of cis-9, cis-12 cis-15 18:3 was greater with ryegrass than with timothy. As a result, the transfer efficiency from dietary intake to secretion in milk was not different between these two treatments. Fewer differences were observed regarding legume forages, as cis-9, cis-12, cis-15 18:3 intake and milk secretion were similar with alfalfa and white clover. However, the transfer of cis-9, cis-12, cis-15 18:3 from diet to milk was highest when feeding alfalfa. In conclusion, forage species fed to dairy goats influence milk composition in terms of fatty acids and protein fractions, which can potentially impact the nutritive value and technological properties of milk.

The major challenges for disposal of waste from fruit processing factories are high transportation costs, limited landfill availability and environmental pollution. Therefore, developing efficient waste management techniques to reduce transportation costs and environment pollution is important. In 2021, global mango production was estimated to be at 57 million tons and mango peel (MP) represents 7–24% of the whole fruit weight. MP has been considered for use as ruminant feed in the form of fresh, dried, or silage. Fresh MP was abundant during the mango season and high in fermentable carbohydrate, which can easily breakdown and pollute the environment if a proper waste management method is not implemented. Thus, in this study, fresh MP was ensiled after sun-drying for one day and then fed to male dairy calves as a roughage source to evaluate its effect on feed intake, digestibility, energy balance, BW gain, feed efficiency and blood metabolites. Eight growing crossbred weaned male dairy calves (Holstein Friesians × Zebu) were allocated into two groups [Control (n = 4) and mango peel silage (MPS, n = 4)]. This experiment lasted for 12 weeks and calves were housed in 3.0 × 1.5 meters individual pen with concrete floor. Before feeding times, the weights of feed ingredients were weighed and mixed for 15 min. Calves were then given their respective diets ad libitum twice a day, at 0800 and 1600 h. Daily feed offered and refusals were recorded to determine the daily feed intake. A digestion trial was performed over the last five days of the experiment. BW and measurements were recorded every two weeks to determine the weight gain and body physical changes. Blood was collected at the end of experiment to analyze serum biochemical parameters. Ensiling improved the energy and protein content and decreased fiber content of MP, thereby improving the forage quality. Feeding a diet containing MPS at 30% of DM weight, compared to an isonitrogenous Control diet increased (P < 0.05) feed intake, energy supply and energy balance, changes in body measurements, weight gain, feed efficiency, and glucose concentration, as well as lowered (P < 0.05) the blood urea nitrogen concentration of male dairy calves. Ensiling fresh MP after sun-drying for one day led to stable, high-DM silage. Therefore, ensiling fresh MP could improve the feed supply for ruminant production and be an effective waste management strategy for fruit processing businesses.

Adding fiber-rich materials to poultry feed can reduce feed cost, but it increases the content of both soluble and insoluble non-starch polysaccharides (NSPs) which decreases nutrient availability. A multiactivity enzyme, AveMix® XG 10 containing glucanase and xylanase, has been developed to ensure the breakdown of the total NSP of fiber-rich feed. A meta-analysis was performed to quantify the effects of this enzyme on the growth performance and nitrogen (N) utilization of broilers, and identify potential modulating factors. The database was made up of 18 trials for a total of 110 dietary treatments conducted between 2003 and 2021. Broilers were fed either based on wheat or corn, and these received a different coding for statistical analysis. The experimental groups were control diets without enzyme or diets with supplementation of the enzyme (ranging from 25 ppm to 100 ppm). Two sub-databases were created to study the impact of growth phase, one for starter (first phase beginning before 7 days of age; 45 dietary treatments) and another for grower/finisher (ending before or at 42 days of age; 65 dietary treatments). Performance criteria were average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR). During the starter phase, enzyme supplementation at 100 ppm linearly increased ADG (0.81 g/d; P < 0.001) and had no impact on ADFI and FCR. During the grower/finisher phase, 100 ppm supplementation increased the ADG of broilers fed with wheat by 6.89 g/d and by 0.58 g/d for the broilers fed with a corn-based diet (Enzyme, P < 0.001; Enzyme × Diet type, P < 0.001). FCR was beneficially reduced by 0.165 for the broilers fed with wheat, and by 0.0471 for the broilers fed with corn (Enzyme, P < 0.001; Interaction Enzyme × Diet type, P = 0.049). ADFI was unaffected by enzyme supplementation. Analysis of N balance during the increased N retained with enzyme in the starter (P = 0.039). During the grower/finisher phase, the enzyme increased N retained (P < 0.001) and N efficiency (P < 0.001), and decreased N excreted (P < 0.001). An interaction between enzyme supplementation and diet type for N retained (P = 0.002) and N efficiency (P = 0.010) occurred due to a higher impact on wheat-based diets. This study shows that the use of AveMix® XG 10 improves the broiler growth performance and N efficiency. These improvements are found to be greater with wheat- vs corn-based diets in the grower/finisher phase.

Heat stress is a major factor affecting animal productivity in tropical countries, with effects on physiological, hormonal, and behavioral responses. This study aimed to assess the differences in these responses between heat-tolerant and less heat-tolerant hair sheep during heat stress. Twenty-four Santa Ines sheep were selected from a group of 80 sheep, with 12 identified as heat-tolerant and 12 as less heat-tolerant based on thermotolerance assessment. The animals were exposed to heat stress in a climatic chamber at an average temperature of 36 °C (1000–1600 h) for 8 days and maintained at 28 °C (1600–1000 h). The rectal temperature, respiration rate, sweat rate, ocular surface temperature, body surface temperature, tympanic temperature, triiodothyronine level, and insulin level were measured. Skin samples were collected on the last day of the cycle for histological analysis. The results showed that the less heat-tolerant sheep had higher rectal and body surface temperatures (P < 0.05). Although no differences in skin morphology were observed between the groups, less heat-tolerant sheep continued to sweat for a longer period after the end of the thermal challenge to lose heat (P < 0.05). Less heat-tolerant animals also presented higher rectal temperatures during cooler hours and required more time to dissipate the excess heat. These findings suggest that there are individual differences in the thermoregulatory responses within the same breed under the same environmental conditions, and that breeding programs could be employed to produce more heat-tolerant, but still productive animals in tropical conditions.

This meta-analysis comprehensively evaluates the impact of production diseases on dairy cattle, examining a variety of physiological, metabolic, and behavioral traits. From an initial set of 3 349 records, a rigorous selection process resulted in 56 relevant articles, highlighting the strict criteria employed. The low inclusion rate of 1.67% underscores the dedication to studying quality and significance. Common reasons for exclusion, such as statistical methodology and the lack of a negative control group, emphasize the necessity for robust scientific investigation. The study reveals key indicators of production diseases, such as decreased milk production, weight loss, a low body condition score, digestive disorders, lameness, and respiratory distress. These findings align with existing knowledge, emphasizing the multifaceted nature of production diseases and their broad impact on dairy cattle health. Diseased animals consistently exhibit higher parameter values, supported by confidence intervals that indicate result precision. Subgroup analyses offer nuanced insights into the specific effects of diseases and interventions on different characteristics. Metritis and Mastitis significantly affect milk production, highlighting the economic implications for dairy farmers. Interventions such as improved milking techniques show promise. Similarly, interventions involving veterinary medications and controlled energy diets effectively mitigate weight loss, a low body condition score, and digestive disorders. The analysis underscores the vulnerability of dairy cattle to reproductive issues, metabolic imbalances, and increased susceptibility to infections. Interventions addressing these challenges include hormone therapy, balanced diets, and vaccination programs. Behavioral changes and feeding habits emerge as significant indicators of dairy cattle well-being. Ovarian cysts are identified as a major contributor to behavioral changes, necessitating targeted interventions. In conclusion, this meta-analysis provides valuable contributions to the field of dairy cattle health, offering specific insights into the effects of diseases and the effectiveness of interventions. These findings inform evidence-based practices for dairy stakeholders, ultimately enhancing animal welfare and promoting sustainable dairy production. However, establishing precise reference values presents challenges, warranting further investigation.