Effect of maternal intrinsic factors on productivity and efficiency at weaning in commercial flock of Pelibuey ewes in the tropic of Tabasco, Mexico

Evaluation of ewe efficiency or productivity is a complex trait because of several factors that are related to produce heavy litters (lamb growth traits) per ewe. The objective of present study was to evaluate maternal intrinsic effects (body weight, body condition score, udder type, litter size, lamb sex) on litter growth traits (litter weight at lambing [LBW] and at weaning adjusted for 70 days [LWW70]) as a criteria of productivity and some indexes of efficiency in Pelibuey ewes. Data of body weight (BW), body condition scores (BCS), and udder types (UT) were taken at lambing, likewise at weaning BW (WBW), on 48 multiparous Pelibuey ewes. Additionally, litter size, sex, birth and weaning weight, were recorded for each offspring; this information was used to calculate LBW, LWW70, average daily gain (ADG), and the following indexes: Ewe efficiency (EEF) expressed as kg of lamb weaned per kg ewe BW at lambing, EEF0.75 expressed as kg of lamb weaned per kg ewe metabolic BW (BW0.75) at lambing, and EEF2 expressed as kg of lamb weaned ± ewe BW gained or lost at waning per kg ewe BW at lambing. For statistical analysis, ewes were classified according to BW (low, medium and high), BCS (low and high) and udder type (I, II, III and IV) at lambing. High BW ewes had greater (P? 0.01) LLW and LWW70 than low BW ewes. Ewe BW at lambing did not affect (P> 0.05) any productivity index. Also, BCS from lambed ewes did not alter (P> 0.05) the productivity parameters. The udder type affected only LWW70 and productivity indexes, being similar among ewes with type-I, II and III udders, but lower in ewes with type-IV udders. Likewise, double litters were heavier at birth and weaning than single litters, affecting EEF and EEF0.75, but not EEF. The Pelibuey ewe’s productivity in humid tropic depends on the maternal BW, udder type at lambing and prolificacy, being a better productivity when ewes have a high BW, double lambing and non-misshapen udders.

Succession in the Caecal Microbiota of Developing Broilers Colonised by Extended-spectrum β-lactamase-producing Escherichia Coli

BackgroundBroilers are among the most common and dense poultry production systems, where antimicrobials have been used extensively to promote animal health and performance. The continuous usage of antimicrobials has selected for resistant bacteria, such as e Extended-spectrum β-lactamase-producing Escherichia coli (ESBL-Ec) . Here, we studied the ESBL-Ec prevalence and successional dynamics of the caecal microbiome of developing broilers in a commercial flock during their production life. Broilers were discriminated as ESBL-Ec colonised or not by selective culturing. Using 16S rRNA gene sequencing, we compared the richness, evenness and composition of the cecal microbiota of both broiler groups and assessed the combined role of age and ESBL status on the microbiota. ResultsWe observed a linear trend in the proportions of ESBL-Ec throughout the broilers' production round, X 2 (1, N = 12) = 28.4, p < .001. Over time, microbial richness was consistently higher in ESBL-Ec free broilers, but significant differences between both groups were found exclusively on day three (Wilcoxon rank-sum test, p = .016). Bray-Curtis distance-based RDA (BC- dbRDA) showed no explanatory power of ESBL status, while age explained 14% of the compositional variation of the caecal microbiome, F (2, 66) = 6.47, p = .001. ConclusionsThis study assessed the role of ESBL-producing E.coli in the successional dynamics of the cecal microbiome in developing broilers and shows that the presence of ESBL-producing E.coli is associated with mild but consistent reductions in alpha diversity and transient compositional differences. We also reported the clonal spread of ESBL and point to the farm environment as a likely source for ESBLs.

Spontaneous outbreak of Pascalia glauca poisoning in sheep in Argentina

Pascalia glauca is a native weed and one of the most common hepatotoxic plant affecting cattle in Argentina. Although experimental P. glauca poisoning have been reported in sheep, no spontaneous cases have been reported in this species. This work describes an outbreak of intoxication after spontaneous consumption of P. glauca, affecting 20% (6/30) sheep of a commercial flock. Affected sheep were ataxic, depressive, with mucous nasal discharge, cough and abdominal breathing. During post mortem examination, liver was swollen and a diffuse enhancement of the reticular pattern (“nutmeg liver”) was visible. Histopathological examination reveals severe and extensive acute diffuse centrilobular hepatic necrosis with hemorrhage. The presence of the toxic plant, the clinical and pathological findings allows us to confirm the etiology of this outbreak.

THE COMBINED EFFECT OF SUCKLING SYSTEM AND WEANING WEIGHT ON MILK TRAITS OF NATIVE SHEEP

Data of the current stud, were collected on 32 Iraqi native sheep aged 2-5 years maintained on commercial flock. At lambing, the 32 ewes were divided into two equal groups, lambs in the 1st group were left with their dams till weaning and then were milked twice daily till they dry off (Continuous), whereas the 2nd group, lambs were separated at night for 12 hr. and the ewes were milked once daily at morning (Restricted). Then each main group was subdivided into two group to be weaned their lambs when they reached 3 or 4 times of their birth weight (WB1 and WB2). Results revealed that ewes of restricted suckling produced significantly (P < 0.05) more post weaning (80.80 vs.49.44 L), total milk yield (135.01 vs. 109.94 L) and sealable milk (99.86 vs. 49.44 L) and had significantly longer lactation period (169.3 vs. 140.2 days) compared ewes in continuous suckling. Also, results obtained indicate that daily gain in weight averaged 0.23 kg from birth to weaning and from birth to marketing and 0.24 kg from weaning to marketing and neither suckling system nor weaning weight affected these trait significantly. It can be concluded that restricted suckling resulted in an increase in sealable milk without any adverse effect on growth of lambs.

Re-current Epizootics of Highly Pathogenic Avian Influenza in Nigeria: Status of Vaccination as Alternate control

Epizootic of Highly Pathogenic Avian Influenza subtype H5N1 in Nigeria was successfully contained during the first wave that lasted from 2006 to 2008 without the use of vaccine. Re-current and more severe outbreak was witnessed in 2015 and there are suspicions that some farmers may have resorted to vaccination to prevent infections in their flocks. We investigate evidence of vaccination in farms and the status of vaccination as alternate control for HPAI in Nigeria. The study was carried out in a cross section of 24 commercial poultry farms in four States in South West and North Central Nigeria. Five hundred and one sera collected randomly were screened by agar gel immunodiffusion (AGID) assay for antibody to group specific influenza A nucleoprotein. One hundred and eight sera obtained from five H5N1 infected poultry farms were also concurrently screened. Reactive sera were further analysed by Hemagglutinin Inhibition (HI) test against H5 antigen using 1% suspension of pooled washed chicken red blood cells. Only 8 out of 501 sera (1.6%) had evidence of influenza A antibody. All of the 8 samples were from one farm with 20 samples collected representing 40% seroconversion at farm level. Three out of those sera were positive for H5 at HI titer of 3log2. All other sera including those obtained from HPAI infected farms were negative for influenza antibody. This study confirms limited antibody response to avian influenza subtype H5 most likely due to vaccination in one commercial flock. Vaccination against avian influenza by farmers desperate to protect their investments may lead to unregulated and suboptimal application of vaccines requiring farmers’ and stakeholders’ engagement to forestall negative impact. Keywords: Avian influenza; Control measures; Recurrent outbreaks; Vaccination status.

Performance characteristics of sows fed enriched diet from weaning to service in a commercial flock

Fielded data from 40 sows together with obtained data from 1999 to 2005 we analysed to determine the performance of sows fed enriched diet from weaning to a service in a commercialflock. The data were on litter size at birth (LTZVT), litter size at weaning (LTZWN), weaning age (WNAGE) forrowing interval (FRINT), purity (PRTY) and reproductive life (PRODLF). Mean value of 9.44(no), 6.04(no), 31.874, 453.58d and 3.65yrs were obtained for LTZBT, LTZWN, WNAGE, FRINT and PRODLF respectively. The influence of parity on sow's performance was analyzed while mortality and sows efficiency of production were determined. Anagonistic relationship existed between production and reproduction traite. Mortality amongst piglets increased with weaning age. Over 80% of sows hold PRINT of less than 157 days, farrowed litters greater than 7 and 55% weaned litter size of over 8. Parity had no influence on sow's performancw. Sow efficiency of production indices showed that sows had 2 farrowing/year, a farrowing rate of 84% and small litter index of less than 17%. The findings of this study have indicated that better performance of sows can be achieved by giving enriched diet (flushing) from weaning to a service rather than the practice of flushing only few days to service

Assessment of laying-bird welfare following acaricidal treatment of a commercial flock naturally infested with the poultry red mite (Dermanyssus gallinae)

The poultry red mite (PRM), Dermanyssus gallinae, a potential vector of pathogens to animals and humans, causes impaired bird welfare. A study investigated changes in behavioural variables, physiological biomarkers, and health parameters following acaricidal treatment of PRM infestation of laying hens on a commercial farm. Mite traps determined the challenge to 12,700 hens before and after drinking water administration of the acaricide, fluralaner (Exzolt®, 0.5 mg/kg; Weeks 0 and 1). Weekly daytime direct observations and night-time video recordings monitored bird behaviours from Weeks -6 through +6. Blood samples were collected from randomly-selected birds (Weeks -6, -1, and +6). Following treatment, mite count reductions (>99%) were statistically significant (P < 0.0001), as were night-time reductions in the percent of hens showing activity, preening, head scratching (all P < 0.0001), and head shaking (P = 0.0007). Significant daytime reductions were observed in preening and head scratching (both P < 0.0001), head shaking (P = 0.0389), severe feather pecking (P = 0.0002), and aggressive behaviour (P = 0.0165). Post-treatment, comb wounds were significantly reduced (P = 0.0127), and comb colour was significantly improved (P < 0.0001). Heterophil/lymphocyte ratio was significantly reduced at Weeks 1 and 6 (P = 0.0009 and P < 0.0001, respectively). At Week 6, blood corticosterone (P = 0.0041) and total oxidant status (P < 0.0001) were significantly reduced, and haemoglobin and mean corpuscular haemoglobin significantly increased (P < 0.0001). Farm production records indicated that those post-treatment improvements were accompanied by significant reductions in weekly mortality rate (P = 0.0169), and significant recovery in mean weekly egg weights (P < 0.0001) and laying rate (P < 0.0001). The improvements in behavioural variables, physiological biomarkers, and health parameters that were observed following the elimination of PRM on a commercial farm indicate that infestations can be a cause of reduced hen welfare.

Can the energetic supplementation of ewes influence the behavioral performance of their newborn lambs?

The present work evaluated the effect of an energetic supplement (an extra 15% of the requirement) intake during the last month of gestation on the suckling behavior of neonatal lambs born from these ewes. The study was performed in a semi-intensive and commercial flock under hot sub humid tropical conditions. 12 Pelibuey ewes and their 20 newborn lambs were included. Five lamb behaviors were evaluated: number of vocalizations (NV), attempts to stand up (ASU), latency to keep stands (LKS), started looking for the udder (SLU) and achieved an effective suckling (AES). Twelve lambs conformed the control group [CG] and came from seven ewes which received an energetic supplementation of 7.37 megajoules of metabolizable energy per day (MJ EM/d). Likewise, eight lambs conformed the treatment group [TG] and came from five ewes which received a high energetic supplementation of 10.85 MJ EM/d. Both groups of ewes gave birth simultaneously. Response variables were initially categorized in low-or-high intensity using their quartile distribution and considering the median value as the reference point and analyzed post-hoc with the Fisher test. Behaviors of high and low intensity in lambs were similar in four of the five variables observed for both treatments. A significant difference was observed in the frequency of ASU, in lambs born from treated ewes when compared with lambs born from control ewes (P = 0.0281). The present results suggest that under semi-extensive breeding systems, the extra supplementation of ewes at 15 % of their energetic requirements during the last pregnancy month is reflected just in a slight improvement of the lamb’s behaviors.

Milk Production of Lacaune Sheep with Different Degrees of Crossing with Manchega Sheep in a Commercial Flock in Spain

The objective of the present study was to evaluate the effect of the grade of crossbreeding (Lacaune x Manchega) and environmental factors on milk production in a commercial flock in Spain. A total of 5769 milk production records of sheep with different degrees of purity of the Lacaune breed crossed with Manchega were used as follows: 100% Lacaune (n = 2960), 7/8 Lacaune (n = 502), 13/16 Lacaune (n = 306), 3/4 (n = 1288), 5/8 Lacaune (n = 441) and 1/2 Lacaune: Manchega (n = 272). Additional available information included the number of parity (1 to 8), litter size (single or multiple), and the season of the year of lambing (spring, summer, autumn and winter). A mixed model was used to evaluate the level of crossbreeding and environmental factors on milk production. The 100% Lacaune sheep presented the highest milk production with respect to the F1 Lacaune x Manchega sheep (p < 0.01), showing that as the degree of gene absorption increases with the Manchega breed, it presents lower milk yield. The 100%, 13/16, and 3/4 Lacaune genotypes had the highest milk yields with respect to the 1/2 Lacaune/Manchega breed (p < 0.001). The Lacaune registered on average 181.1 L in a period adjusted to 160 days of lactation (1.13 L/ day). Likewise, the parity number, litter size, and season of lambing effects showed significant differences (p < 0.01). It was concluded that 13/16 and 3/4 Lacaune/Manchega ewes presented the highest milk yields with respect to the other crosses.

Factors Determining Survivability Traits of Charollais, Kent Lambs, and their Crossbreds During Rearing

The aim of this work was to evaluate the effect of birth weight on the survival of Charollais, Kent and their crossbreds in breeding and also on their meat performance for Charollais and Kent lambs. Data were evaluated for the six years period in the commercial flock. The total number of lambs used for evaluation was 1,197. The data were passed through the SAS STAT program using the MIXED method. In the model equation, all the dependent variables of the survival indicator were significantly statistically detectable with a significance level of P < 0.01. The results indicated that survivability lambs was significantly influenced by birth weight and litter size (P < 0.05). Meat performance of lambs was affected the most combined year and month, breed and litter size (P < 0.05). The results suggest better survivability abilities for the crossbred than the pure-bred population. Despite the lack of meat performance data, it is interesting to consider a possible selection program for the breeds, Charollais and Kent, to improve the survival of lambs for extending extensive farming methods. However, also by improving flock management we will achieve better survivability results for lambs.