Egg Production and Biological Activities in Laying Hens are Affected By Different Molting Programs

This study was conducted to compare two molting methods by using aluminum sulfate (2.5 g/kg) and diet withdrawal on productivity, eggs quality, and lipid profile of laying hens. A total of 180 Hy-line Brown hens 80 weeks of age were randomly assigned to three replicates of three treatments of 30 hens/treatment from 70–87 weeks of age; hens were exposed to one of the following two molt groups: T1, aluminum sulfate (2.5 g/kg) and T2, feed withdrawal(14 days). Egg production was recorded daily/hen in each cage and weekly for each treatment. Following the forced molting, feed consumption was recorded and calculated weekly. Feed conversion rate as a feed/g egg mass was calculated weekly for each treatment. Haugh unit was determined by [11]. At the end of the experiment blood samples were collected from nine laying hens/treatment from the extrinsic vein using a 5mL sterilized syringe with heparin for biochemical determination parameters. Blood samples were centrifuged at 4000rpm for ten minutes. Plasma and serum were separated and stored (- 20°C) until the biochemical measurement. Cholesterol, Triglycerides, Total Protein, Albumin, Globulin, ALT, and AST were determined in this study. The data were analyzed using (ANOVA) to analyze the difference between treatments. A significant difference was identified between treatments, by using Duncan’s test for multiple comparisons. The results of this study indicated that hens subject to feed withdrawal treatment showed a significant (p < 0.05) percentage of body weight loss compared to those in the feed with aluminum (2.5g/kg). We did not find significant (p>0.05) differences in hens performance for all treatments in the post molt for 56 days. Our data showed hens had significantly lower (p < 0.05) in hen day egg production when compared with other treatments after molting, also, the egg weight showed no significant differences between treatments. The results showed a significant (p<0.05) difference in albumin and globulin between molt methods. Our experiment indicated that aluminum sulfate (2.5 g/kg) and feed withdrawal represent a viable alternative to the molting method for the successful induction of molting and retention of post molt performance.

322 Impact of Feed Restriction and Fasting Suffered in Assembly Centers and Transportation on Energy Balance and Gut Permeability in Unweaned Angus-holstein Calves

Twenty unweaned Angus-Holstein calves (44.1 ± 2.0 kg; 14.7 ± 0.63 d) were used to evaluate the effects of feed restriction and fasting on energy balance (serum concentration of glucose, BHBA, and NEFA), and intestinal permeability (serum concentration of citrulline, Cr-EDTA, lactulose, and D-mannitol). Calves were randomly assigned to 1 of 4 treatments that simulated assembly center management and transportation; Control (CT; n = 5): from d-4 to -1, 2.5 L of milk replacer (MR) twice daily, concentrate and straw ad-libitum; Mild (MD; n = 5): only MR (d-4 to -1) as described for CT, and on d-1 feed withdrawal for 9 h; Moderate (MO; n = 5): only MR as described for CT and on d-1 feed withdrawal for 19 h; and Severe (SV; n = 5): only 2.5 L of a hydrate solution (HS) twice daily (d -4 to -1) on d-1 feed withdrawal for 19 h. From d 0 to day 7 all calves were fed MR, concentrate, and straw ad-libitum. Data were analyzed using mixed models with repeated measures. At d -1 for SV and d 0 in all restricted calves (MD, MO, SV), serum glucose concentration was lesser (P &lt; 0.01) compared with CT. At d 0 NEFA and BHBA serum concentrations increased (P &lt; 0.01) in SV calves compared with the other treatments. Serum citrulline concentration (P &lt; 0.05) was lower for SV on d -1 and greater for CT on d 2 compared with other treatments. CT calves had the lesser concentration of Cr-EDTA (d -1 and d 0, P =0.04), lactulose (d 0, P =0.02), and D-mannitol (d 0, P =0.01) compared with MD, MO, and SV. The degree of dietary restriction, the type of liquid diet, and amount of fasting hours affected calves’ serum concentration of markers indicative of energy balance and gut permeability.

Understanding the effects of intramuscular injection and feed withdrawal on Salmonella Typhimurium shedding and gut microbiota in pullets

Background Gut microbiota plays a key role in health, immunity, digestion, and production in layers. Factors such as environment, diet, diseases, stress, and flock management significantly affect gut microbiota; however, it is not known how potential stressors such as intramuscular injections or feed withdrawal alter the composition of gut microbiota that result in increased the shedding level of foodborne pathogens. In the current study, the effects of intramuscular corticosterone injection and feed withdrawal were evaluated to understand their role in Salmonella Typhimurium shedding and changes in the composition of gut microbiota in layers. Results Salmonella shedding was observed for 8 weeks post-infection. There was a significant increase in Salmonella Typhimurium count after intramuscular injection and feed withdrawal. The Salmonella infected and the negative control groups showed significant differences in the abundance of different genera in gut microbiota at week 1 and up to week 7 post infection. The infected group showed a significant reduction in alpha diversity of gut microbiota. Firmicutes reduced significantly (P < 0.05) after intramuscular injection, while the feed withdrawal groups did not cause any significant changes in Proteobacteria-Firmicutes ratio. Furthermore, intramuscular injection resulted in a significant change in alpha diversity of gut microbiota. Conclusions Exposure of chicks to relatively low dose of Salmonella Typhimurium can lead to persistent shedding in pullets. The Salmonella Typhimurium infection disrupted the gut microbiota composition immediately after infection. The potential stress of intramuscular injection and feed withdrawal significantly increased the Salmonella Typhimurium count in faeces. The intramuscular injection also resulted in a significant alteration of the Proteobacteria-Firmicutes ratio, which could increase the risk of dysbiosis.

Evaluation of existing poultry processing and marketing in the wet market of Gazipur city in Bangladesh

The poultry selling and processing practices followed in the poultry wet markets of Bangladesh are always being overlooked unknowingly. The research was conducted to observe the existing scenario of poultry selling and processing practices at the selected wet markets located in the Gazipur City Corporation of Bangladesh. A total of 43 poultry selling shops were randomly selected and interviewed using a semi-structured questionnaire. It was surprising to observe the absence of female personnel and involvement of few (6.9%) people over the age of 50 years in the wet markets. All the persons engaged in poultry selling and processing had no institutional training. The shops found to be abstained from following some important practices such as feed withdrawal period, isolation of diseased birds, ante and post mortem inspection. The proper bleeding time (1-2) min was recorded in 58.2% cases. The killing cone was recognized as the best device in terms bleeding time. The 72.1% of the outlets never cleaned the carcass prior to deliver the customers. The absence of ante- and post-mortem inspections may cause a great threat of disease outbreak. Taken together, the poultry selling and processing practices followed in the wet market needs to be assessed carefully to deliver safe and quality meat to the customers. In addition, organizing basic training on pre-slaughter management and processing for both seller and processor and also ensuring the regular ante- and post- mortem inspection could improve the present situation in order to produce quality poultry meat. Progressive Agriculture 31 (3): 205-217, 2020

Effect of Feed Withdrawal Stress on Reproductive Tissue, Sex Steroids and mRNA Expression of IGF-1, Survivin, Caspase 2 and HSP 70 Gene in the Ovarian Follicles of Japanese Quail

Background: Japanese quail, similar to domestic chicken, is equally sensitive and susceptible to stress but limited literatures are available so far. Therefore, this study was aimed to investigate the effect of feed withdrawal stress on the changes in reproductive tissues, steroid hormones and gene expression in Japanese quail. Methods: Forty two quail hens (10weeks) were individually caged and subjected to feed withdrawal for a period of 10 days without water restriction. Six birds each were sacrificed on 0, 1, 2, 4, 6, 8 and 10 day. The reduction in oviduct weight and serum concentration of steroid hormones was evaluated. The quantitative expression of IGF-1, Caspase-2, Survivin and HSP-70 genes were performed in ovarian follicles using real-time PCR. Result: No hierarchial follicles were detected after day 6. The ovary and oviduct weight was significantly reduced on day 2 and 4 respectively. The serum estrogen and progesterone were declined significantly when corticosterone was increased from day 1. The IGF-1 gene expression was significantly (P less than 0.05) down regulated in yellow and atretic follicles. The gene expression of Survivin and caspase-2 was up-regulated in F3 follicle. It concludes feed withdrawal brings noticeable change in reproductive tissues, steroid hormones and associated gene expression in Japanese quail.

Fasting Finisher Pigs before Slaughter Influences Pork Safety, Pork Quality and Animal Welfare

The final phase in pork production is the transport of finisher pigs to the slaughterhouse. Fasting is one of the parameters that influence the stress coping ability of the pigs during transport and lairage. When implemented correctly with attention to the local factors, pre-slaughter fasting can improve animal welfare, pathogen risk and carcass hygiene. The length of pre-slaughter feed withdrawal time is important to the success of the production practice. In practice, a fasting time before slaughter between 12 and 18 h enhances pork safety, pork quality, and animal welfare. This means that communication between producer and slaughterhouse is essential when planning the fasting and lairage times to avoid carcass and technological pork quality problems (such as pale, soft, and exudative (PSE) meat or dark, firm and dry (DFD) meat).

273 Impacts of commingling on health and productive responses of beef heifers during feedlot receiving

This experiment compared physiological, health, and performance responses of beef heifers assigned to different commingling schemes (1, 2, or 4 sources/pen) during a 56-d feedlot receiving period. Ninety-six recently weaned Angus-influenced heifers were purchased from a commercial auction facility. Heifers originated from 4 cow-calf ranches, and were reared in the same herd within each ranch since birth. Heifers were loaded by source into commercial livestock trailers at the auction yard, and transported for 8 h to stimulate the stress of a long haul. Heifers were not mixed with cohorts from other sources prior to and at the auction yard. Upon arrival at the receiving yard (d -2), shrunk body weight (BW) was recorded, and heifers were maintained in 4 paddocks by source with ad libitum access to hay, water, and a mineral supplement for 36 h. On d 0, heifers were ranked by source and shrunk BW and allocated to 1 of 24 drylot pens (4 heifers/pen) containing: 1) heifers from a single source (NOCOM, n = 8 pens), 2) heifers from 2 sources (COM2, n = 8 pens), or 3) heifers from 4 sources (COM4, n = 8 pens). From d 0 to 55, heifers had free-choice access to water and a total-mixed ration. Heifers were assessed for bovine respiratory disease (BRD) signs and feed intake was recorded from each pen daily. Blood samples were collected from all heifers on d 0, 6, 13, 27, 41, and 55, and shrunk BW (after 16 h of water and feed withdrawal) was collected on d 56 for average daily gain (ADG) calculation. Final shrunk BW and ADG did not differ (P ≥ 0.83) between NOCOM, COM2, and COM4 heifers (0.85, 0.88, and 0.82 kg/d of ADG, respectively, SEM = 0.08). No treatment effects were detected (P ≥ 0.77) for feed intake and feed efficiency, as well as plasma concentrations of haptoglobin and cortisol. No treatment differences were noted (P ≥ 0.49) for morbidity (53.1, 68.7, and 56.2% of NOCOM, COM2, and COM4 heifers diagnosed with BRD, respectively; SEM = 9.7) or mortality during the experiment. A similar (P ≥ 0.97) proportion of NOCOM, COM2, and COM4 heifers diagnosed with BRD required at least two treatments to recover from sickness. In turn, a third treatment was not required for NOCOM heifers, which was less compared with COM4 (P = 0.05) and similar (P = 0.23) compared with COM2 heifers. Perhaps the number of heifers assigned to commingled pens, and resultant pre-existing social groups, was not sufficient to stimulate the stress reactions caused by social destabilization.