Livestock Science最新文献

The objective of the present study was to investigate the optimal inclusion rate of 2 independent extracts with different properties derived from the olive industry [triterpenic acid extract (TAE) and a polyphenol extract (PE)] on productive performances in broiler chickens from 0 to 45 d under challenging conditions. In addition, antiparasitic protection of the TAE was evaluated at d 21 and d 28 through intestinal scoring and oocyst counts, as well as the blood antioxidant activity of the PE at d 45. Wood shavings as bedding material came from a commercial farm with a coccidia load sufficient to create a subclinical coccidiosis situation with minor macroscopic lesions, and a nutritional challenge was imposed using poor raw materials to cause intestinal dysbiosis. There were 9 dietary treatments (8 replicates/treatment and 15 broiler chickens/pen), a positive control (PC) supplemented with commercial coccidiostat (Na monensin), 4 increasing concentrations of TAE (30, 60, 90, and 120 ppm), and 4 increasing concentrations of PE (10, 20, 30, and 40 ppm). For the overall experiment the PC had greater average daily gain (ADG) and average daily feed intake (ADFI) (P < 0.001) than the mean of TAE treatments. Besides, the ADG, body weight, and ADFI increased linearly throughout the whole experiment as the TAE level of the feed increased. With respect to the anticoccidial activity, the 120 ppm TAE treatment showed greater concentration of E. acervuline DNA copies at 21 d than the 30 ppm TAE treatment (P < 0.05), the rest of the treatments being intermediate. Concerning the PE treatments, for the overall experiment, ADG was the greatest in the PC treatment (P < 0.001), and the ADFI was similar in the PC treatment to the mean of PE treatments. There was no effect of the PE on antioxidant activity. In conclusion, under the conditions of this study, the inclusion of TAE does not reach the productive performance indicators achieved by a commercial coccidiostat in our intestinal challenge situations. Also, the inclusion of PE has a positive effect on productive performance on the overall period.

The experiment was conducted to evaluate the inclusion of different sources of fat on the intake and digestibility of nutrients, serum metabolites, and growth performance of feedlot lambs. Forty male Dorper × Santa Inês lambs (averaging 22.27 ± 2.79 kg of body weight; mean ± standard deviation) with approximately 4 months were distributed in a completely randomized design. Five experimental diets were tested: no added fat (NAF), whole soybeans (WSB), calcium salts of fatty acids (CSFA), soybean oil (SO), and full fat corn germ (CG). Nutrient intake was affected by the inclusion of different fat sources in diets (P < 0.05) except for the neutral detergent fiber (aNDFomp). The CSFA diet showed the highest nutrient apparent digestibility (P < 0.05), except for the digestibility of aNDFomp and non-fibrous carbohydrates. Nitrogen retention was higher (P = 0.003) in animals fed the CSFA diet. Albumin (P = 0.038), albumin:globulin ratio (P = 0.042), glucose (P < 0.001), and cholesterol (P = 0.032) were affected by the inclusion of different fat sources in feedlot lamb diets. Lambs fed NAF and CSFA diet showed the highest average daily gain (P = 0.001) and final body weight (P = 0.036). The use of 3.5 % calcium salts of fatty acids (protected fats); improves the diet digestibility and promoted the highest growth performance parameters in feedlot lambs.

There is little published research on dairy-beef heifer systems or comparisons of heifer and steer dairy-beef production. Furthermore, given its impact on the productivity and economics of dairy-beef systems, any comparison of gender must also consider potential interactions with stocking rate (SR). The objective of this study was to evaluate the variability of physical and economic performance, greenhouse gas emissions, feed-food competition and pasture land-use of dairy-beef production steer and heifer systems at differing stocking rates. Performance data from a two (gender: Steers and Heifers) x two (SR: Low and High) x two (breed-types: Early-maturing (EM) and Late-maturing (LM) factorial experiment was used to parameterize a bio-economic farm systems model. Low SR animals were heavier, had higher fat scores and better conformed at slaughter. High stocking rate resulted in greater carcass output per hectare and subsequently were, on average, 22 % more profitable than their Low SR counterparts. Late-maturing animals were found to be more profitable than early-maturing, and steers were more profitable than heifers. GHG emissions of the eight treatments investigated ranged from 10.7 to 17.7 kgs of carbon dioxide equivalents (kg CO₂eq) per kilogram of carcass weight produced, with both High SR and heifer systems having lower GHG emissions per kg of product than their Low SR and steer counterparts. Human edible protein efficiency was only favorable for the steer systems. High SR systems had, on average, lower land use per kg of product than their Low SR counterparts. Results from this study indicate that no single treatment was optimal across the range of performance metrics considered.

EU legislation forbids the systematic use of tail docking. Tail-biting is a welfare problem in swine production, including weaners. In Portugal, like in Spain, Greece, Italy, Croatia, and Serbia the transport of five-week-old pigs to the abattoir is a common practice. This study aimed to evaluate the occurrence of tail docking and tail-biting in weaners and associate it with the farm of origin/grouping centre and meat inspection results. Weaners were observed at 6 abattoirs in the Central Region of Portugal. Origin, docking status, tail lesions, and carcass condemnation were recorded during post-mortem inspection. A total of 15,863 weaners were assessed, 12.6 % came from assembly centres, 22 % with docked tails, 21.5 % with tail lesions, and 60 weaners were condemned. Tail-biting lesions were significantly associated with having an undocked tail. This association was stronger if the weaners came from intermediate assembly centres compared to weaners that came directly from the farm (AOR = 5.642, 95 %CI 2.885 to 11.030, P = 0.017 versus AOR = 1.403, 95 %CI 1.062 to 1.853, P < 0.001). The rate of carcass condemnations was higher among weaners presenting tail lesions (6.15 versus 3.13/1000 in weaners without tail lesion). The most frequent cause of condemnation was polyarthritis/purulent arthritis (1.6 per 1000 weaners). Our study shows that tail-docking is still practiced, and having the tails undocked is an additional vulnerability in what concerns tail-biting, especially in those weaners that do not go directly from the farm to the abattoir, with intermediate stops at assembly centres. New regulation is needed that takes into account this further deterioration in animal welfare.

This study aimed to evaluate body and gastrointestinal development in broilers chicks subjected or not to pre-housing fasting and different diet physical forms during the first week of housing. Nine hundred chicks were distributed into a completely randomized design in a 3×3 factorial arrangement: 0, 24 and 48 hours(h) of fasting; mashed (MM), crushed (CC) and micropelletized (MP) physical forms. For each fasting period, 300 animals were housed in protection circles with 100 chicks each. On days 1, 3, 5 and 7 of feeding, six animals were randomly selected, previously weighed and euthanized to obtain organs biometrical and histological data. Chicks fasted for 24 h and 48 h were lighter compared to the 0 h group and the 24-h fasting x MP interaction had a positive impact on body weight at d7 (P<0.05). Although fasted chicks presented lower body weight, small intestine, liver and gizzard were heavier, and presented greater yolk sac consumption (YSC; P<0.05). There were no alterations in the duodenal mucosa (DM) in pre-housing fasting animals (P>0.05). Despite the diet physical form and pre-housing fasting interactions for villus height (VH) and absorptive area (AA) on d1, only diet physical form affected DM, where greater VH and AA on d7 were observed in CC and MP groups (P<0.05). Animals fed MP after 48 h fasting presented smaller VH and AA compared to chicks fed the same diet after 24 h and were similar to the 0 h group (P<0.05). On d1, YSC was similar among groups of the same diet, but for those fed with MP(P<0.05). The 48 h-fasted group presented heavier intestines relative weights (IRW) at d1(P<0.05). Furthermore, the 0 h group fed with CC presented higher IRW, whereas MP showed the lowest IRW over the first week (P<0.05). The DM development (kinetics) showed an increase in VH and AA overtime in all groups, which was more pronounced in 48 h-fasting chicks throughout the first week, showing the highest increase in VH when fed with MP (P<0.05). VH:CD ratio was similar along the first week in MP groups, regardless of the fasting period but more pronounced in the 24 h group fed MM and CC (P<0.05). Therefore, 24 h fasting associated to MP diet may be the most efficient management practice. Collectively, these findings suggest pre-housing fasting is strongly associated with diet physical form at the first week of housing and should be considered to achieve greater performance in broilers.

This study aims to investigate the effects of alternative energy feedstuff supplementation containing condensed tannin (CT) on palisade grass pastures, focusing on intake, nutrient digestibility, animal performance, ruminal and blood parameters, nitrogen use efficiency (NUE), and its impacts on the ruminal bacterial community in backgrounding Nellore young bulls. Two experiments were conducted simultaneously. Animal performance was evaluated in Experiment 1. The experimental design was a completely randomized block; ninety Nellore bulls (Bos taurus indicus) with an average initial body weight (BW) of approximately 240 ± 5 kg were used (64 as testers and 26 as regulators). The feed intake, digestibility of dry matter and nutrients, ruminal parameters, NUE, and the impact on the ruminal bacterial community were evaluated in Experiment 2. The experimental design was a 4 × 4 double Latin square involving eight Nellore bulls with an average initial BW of 290 ± 8 kg, all of which were cannulated in the rumen. The treatments consisted of energy supplementation at 0.3 % of BW with peanut skin (PS), 0.3 % of BW with sorghum grain (SG), 0.3 % of BW with soybean hulls (SHs), and a control treatment with a supply of mineral salt ad libitum. The total digestible nutrient intake was lower in animals that received only mineral supplements (p < 0.005). The dry matter (DM) intake decreased with treatment PS, while the DM and nutrient digestibility increased (p < 0.005). There was a reduction in ruminal ammonia nitrogen and an improvement in NUE in the PS treatment (p < 0.005). However, the bacterial and Archaea populations were unaffected (p = 0.619). Individual animal performance and gain per kg were increased in the treatment with supplements containing or without CT compared to the mineral supplement (p < 0.001). The NUE improved in treatments PS, SG, and SH (p < 0.01). Feedstuff supplementation using no edible foods by products containing CTs is an effective alternative energy source for Nellore bulls grazing on palisade grass during the rainy season. Additionally, it can be used to mitigate the environmental impacts of N excretion.

The objective of this study was to evaluate the effect of sex and birth weight classes (BWC) on the colostrum intake, performance, permanence in the production system, immune response and microbiome of piglets in the farrowing and nursery phases. A factorial design was used with two sex categories (female and male) and three BWC (low - 0.8 to 1.1 kg; medium - 1.101 to 1.4 kg; and high - 1.401 to 1.7 kg). A total of 757 piglets in the farrowing phase and 228 piglets in nursery phase were used. Serum glucose concentration at birth and 24 hours, colostrum intake, performance parameters, removal rates, mortality, medication, and serum concentrations of immunoglobulin G (IgG), interleukin 10 (IL-10) and tumor necrosis factor alpha (TNF-α) on the 4^th day after weaning, and fecal microbiome on the 6^th day of nursery were evaluated. The serum glucose levels were not changed (P > 0.05). Piglets with high birth weight ingested more colostrum (P < 0.001). Low birth weight piglets (P = 0.077) and males (P = 0.027) had a higher removal rate and mortality. A higher percentage of females with high birth weight required medication (P < 0.001). The body weights of piglets at all weighings were higher for those with high birth weight (P < 0.001). The daily weight gain and feed intake during the nursery phase were affected by the BWC (P < 0.001). Low birth weight piglets had a lower concentration of TNF-α (P = 0.009), and there was no difference in IL-10 concentration (P > 0.05). Males tended to have higher serum IgG concentrations (P = 0.067). Medium- and high-weight piglets, as well as males, showed a higher abundance of pathogenic bacterial species (Fusobacterium mortiferum, Campylobacter jejuni, Clostridium neonatale and Ruminococcus torques). In conclusion, females had a higher rate of permanence in the production system and a fecal microbiome with a lower abundance of pathogenic bacteria, and low birth weight piglets had lower colostrum intake with reduced zootechnical indices.

The effect of bushfires (also known as wildfires) on the Australian livestock industry extends beyond the direct loss of animals and farming assets, with anecdotal reports of increased incidence of dark meat color defects in beef carcasses at grading (AUSMEAT color score >3) from bushfire affected cattle. To understand the association between bushfire exposure and meat color, an investigation using historical MSA (Meat Standards Australia) grading data, pasture data and bushfire data over two bushfire seasons (2018–2019, 2019–2020) was conducted. For bushfire affected beef cattle (n = 451 299), predictive models were developed to estimate the association between bushfire exposure and (1) loin color at grading, and (2) the incidence of ‘dark color’ defects. Both models incorporated bushfire exposure, production, and animal variables, with hierarchical random effects specified as plant/processing date/consignment. For the two predictive models, distance of the animal's originating property from closest bushfire (km), the days the animal was exposed to bushfire, feed type (grass, grain), the use of hormone growth promotants (HGPs; no, yes), the interaction of distance of property from closest bushfire and feed type, and days of bushfire and HGP treatment, were all significant predictors of loin color outcomes (P < 0.05 for all). Model 1 indicated that as distance from closest bushfire decreased, loin from grain-fed animals had darker color (P < 0.001), and that as days of bushfire exposure increased, HGP treatment exacerbated dark color outcomes for grain-fed animals but had little effect on the consistently high color scores of grass-fed HGP treated animals (P = 0.001). For model 2, the highest predicted proportion of dark color defects (11.8 %) was for grass-fed, HGP treated cattle, 10 km from the closest bushfire and exposed to 150 days of bushfire. The lowest predicted proportion of dark colour carcasses (1.3 %) was for grain fed, non-HGP treated cattle, 30 km from the closest bushfire, with no change associated with increasing days of bushfire. Cattle can be categorized in order of increasing susceptibility to dark color defects as a result of being exposed to bushfires; grain-fed cattle with no HGPs were the least susceptible to dark color defects, and grass-fed cattle with HGP treatment were the most susceptible. Remediation strategies are discussed in relation to cattle susceptibility to adverse loin meat color outcomes associated with bushfire exposure.

Phytogenics are bioactive plant components that are intensively researched for their beneficial effects on poultry performance and health. Ongoing nutrigenomic studies provide mechanistic evidence for phytogenic benefits at the cellular molecular level. Critical biomarkers for gut function and health have been shown to be responsive to stressor challenges as well as to phytogenic administration. In particular, it has been shown that phytogenics induce opposite effects to the detrimental ones induced by stressor challenges, thereby providing opportunities to alleviate the negative effects of stressors on poultry production and health. Therefore, credible promotion of poultry gut function and health via phytogenic administration results in better feed utilization, higher production, healthier products, better poultry welfare, less environmental impact and production sustainability respecting the circular economy and green deal initiatives. Furthermore, phytogenics as valuable parts of overall disease prevention strategies align with the One Health initiative for healthy humans, healthy animals and a healthy planet.

We determined the influence of post-weaning development method on rangeland grazing patterns of beef heifers during early and late spring. We compared behavior of heifers wintered on rangeland (group-fed cake, GFC or self-fed protein, SFP supplements during winter) or in a pen where they were fed silage (pen-fed silage, PFS). In April and May of each year (n = 3), heifers (n = 95) were fitted with Lotek 3300LR GPS collars and monitored 18 days each month. PFS heifers traveled farther than SFP and GFC counterparts on the first few days in April (P < 0.05). PFS heifers covered larger areas of the pasture compared to GFC and SFP (P < 0.05) counterparts during May. All heifers followed trajectories of similar sinuosity (P > 0.05). On most days, PFS heifers allocated more time to resting (April) and traveling (April and May) than heifers in SFP treatment (P < 0.05). SFP heifers spent significantly more time grazing than PFS and GFC counterparts during April (P < 0.01). However, differences in foraging patterns decreased through time. All heifers spent more time grazing (P < 0.01) on cloudy days with higher humidity during April and less time grazing on windy and rainy days in May (P < 0.05). Pixel Normalized Difference Vegetation Index (NDVI) appeared to influence pasture use patterns regardless of treatment. Traveling and resting time, as well as pixel residence time were the three variables that best discriminated heifers into treatment groups (P < 0.01). Collared heifers tended to associate with heifers of their own/other treatment group (prevailing PFS-GFC or GFC-SFP heifers). The social role of a collared heifer in the herd did not appear to be associated with development treatment. Post-weaning development protocols modified movement, activity, and habitat use of heifers during early spring. Initial animal state and/or metabolic memory may have been responsible for the differences observed. Such differences, however, were possibly attenuated by social facilitation.