scholarly journals Genetic analysis of disease resilience in wean-to-finish pigs from a natural disease challenge model

2020 ◽  
Vol 98 (8) ◽  
Author(s):  
Jian Cheng ◽  
Austin M Putz ◽  
John C S Harding ◽  
Michael K Dyck ◽  
Frederic Fortin ◽  
...  

Abstract The objective was to estimate the genetic parameters of performance and resilience of growing pigs under disease. Data were from 3,139 Yorkshire × Landrace wean-to-finish pigs that were exposed to a natural polymicrobial disease challenge that was established by entering naturally infected animals into a nursery barn, targeting various viral and bacterial diseases. The challenge was maintained by entering batches of 60 or 75 healthy nursery pigs every 3 wk in a continuous flow system. Traits analyzed included average daily gain (ADG), feed intake (ADFI) and duration (ADFD); feed conversion ratio (FCR); residual feed intake (RFI); mortality (MOR); number of health treatments (TRT); health scores (HScore); carcass weight (CWT), back fat (CBF) and loin depth (CLD); dressing percentage (DRS); lean yield (LYLD); day-to-day variation in feed intake and duration (VARFI and VARDUR); and the proportion of off-feed days (OFFFI and OFFDUR). Analyses were performed by mixed linear models with genomic relationships. The resilience traits, such as TRT, MOR, and HScore, were lowly heritable (up to 0.15) but had high genetic correlations with each other. Performance traits, such as ADG, ADFI, ADFD, FCR, RFI, and carcass traits, were moderate to highly heritable (0.17 to 0.49). Heritabilities of resilience indicator traits such as OFF and VAR had low to moderate heritabilities (0.08 to 0.23) but were higher when based on duration vs. amount. ADFI had a low genetic correlation with ADFD (0.13). ADG in the challenge nursery had stronger negative genetic correlations with both TRT and MOR than ADG in the finisher (−0.37 to −0.74 vs. −0.15 to −0.56). ADFI and FCR had moderate negative (−0.21 to −0.39) and positive (0.34 to 0.49) genetic correlations, respectively, with TRT and MOR. ADFD and RFI had very low genetic correlations with TRT and MOR. CWT and DRS were moderately negatively correlated with TRT and MOR (−0.33 to −0.59). Resilience indicator traits based on feed intake or duration had moderate to high positive genetic correlations with TRT (0.18 to 0.81) and MOR (0.33 to 0.87). In conclusion, performance and resilience traits under a polymicrobial disease challenge are heritable and can be changed by selection. Phenotypes extracted from feed intake patterns can be used as genetic indicator traits for disease resilience. Most promising is day-to-day variation in intake duration, which had a sizeable heritability (0.23) and favorable genetic correlations with MOR (0.79) and treatment rate (0.20).

2021 ◽  
Author(s):  
Maggy Palesa Mabena ◽  
Moses Ratsaka ◽  
Thobela Nkukwana ◽  
Ingrid Malebana ◽  
Douglas Nkosi

Abstract This experiment evaluated varying levels of Amarula (Sclerocarya birrea A. Rich) nut cake (ANC) on growth performance, nutrient digestibility and carcass characteristics in pigs. Thirty Large White × Landrace (LW × LR) pigs were stratified by weight (average live weight of 20 ± 5 kg) and randomly allocated to the five experimental diets that contained 0 (control), 50, 100, 150 and 200 g ANC/kg DM. Each pig served as a replicate unit, housed individually. Bodyweight, feed intake, average daily gain (ADG) and feed conversion ratio (FCR) were recorded weekly throughout the trial period. On completion of the growth trial, following a 3-day adaptation, a nutrient digestibility study was conducted over 5 days. Thereafter, pigs were fasted for twelve hours, weighed, slaughtered, and carcass samples were collected for analysis. Feed intake was not affected by dietary treatment, but ADGs were reduced at ANC levels > 15%, resulting in poor FCR. Protein digestibility was reduced at ANC levels > 15%, while ether extract and fibre levels increased. Warm and cold carcass weights were lower at ANC levels > 15, with improved meat redness and lightness. It was concluded that ANC could replace SBM in the diet of growing pigs at less than 15% inclusion level.


Animals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1017
Author(s):  
Jordi Camp Montoro ◽  
Edgar Garcia Manzanilla ◽  
David Solà-Oriol ◽  
Ramon Muns ◽  
Josep Gasa ◽  
...  

This study aimed to (1) investigate the effect of birth and weaning body weight (BW) on performance indicators of grow-finisher pigs and (2) estimate birth and weaning BW cut-off values in order to identify slow growing pigs (SGP). Pigs (n = 144) were classified as SMALL (0.9 ± 0.13 kg) or BIG (1.4 ± 0.20 kg) at birth and re-classified as SMALL (5.4 ± 1.6 kg) or BIG (6.3 ± 1.91 kg) at weaning. Individual BW was recorded bi-weekly, and feed intake was recorded on a daily basis. Average daily gain (ADG) and feed intake, feed conversion ratio (FCR) and days to target slaughter weight (TSW) were calculated. SMALL–SMALL pigs had lower ADG (p < 0.05) requiring 167.1 days (i.e., 14.2 extra days) to TSW (p < 0.05) compared with BIG pigs at birth and/or weaning. However, FCR was similar between groups (p > 0.05). Pigs weaned at <3.7 kg BW would likely be SGP. Pigs born at ≥1.1 kg BW or weaned at ≥6.4 kg BW are more likely to reach TSW at 22 weeks of age. The results suggest that birth BW might not be the best predictor for subsequent performance, as some small-born pigs were able to catch up with their bigger counterparts. The cut-off values identified could be used to design specific management and nutritional strategies for SGP.


1978 ◽  
Vol 27 (3) ◽  
pp. 345-354 ◽  
Author(s):  
G. A. Lodge ◽  
D. Lister ◽  
J. D. Wood ◽  
M. S. Wolynetz

ABSTRACTIn an experiment which showed that the results of a genotype comparison are influenced by the design of the test, 16 castrated male and 16 female pigs of each of Large White (LW) and Gloucester Old Spot (GOS) breeds were allocated equally among four treat- ments: WW—rationed by weight and slaughtered by weight; A A—rationed by age and slaughtered by age; AW—rationed by age and slaughtered by weight; and WF—rationed by weight and slaughtered after a common total feed intake. The experiment was designed so that performance of LW would be similar on all treatments, and the degree to which the GOS differed from the LW on each of these treatments was then evaluated. All pigs started on the experiment at 12 weeks of age, at which time mean weight of the LW was 14% greater than the mean for the GOS. The only between- breed difference that was statistically significant (P<0·05) on all treatments was weight of lean. Average daily gain and efficiency of feed conversion were significantly different between breeds only on the WW treatment. Weight of fat was significantly different on WW and AW but not on AA or WF.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 45-46
Author(s):  
Austin M Putz ◽  
John Harding ◽  
Micheal Dyck ◽  
PigGen Canada ◽  
Frederic Fortin ◽  
...  

Abstract Resilience is defined as the ability to maintain productivity through any number of stressors such as disease or heat stress. A total of 2273 animals, in groups of ~60–75 piglets, were sent through a natural disease challenge barn every three weeks that consisted of three phases: i) a healthy quarantine nursery to collect immune parameters, ii) a challenge nursery, and iii) a challenged finishing unit which was attached to the challenge nursery. Individual feed intake (FI) was collected in the finishing unit with IVOG® feeders and aggregated into daily totals. Three resilience phenotypes were extracted from the individual trends in feed intake over time, including the root mean square error (RMSE), the quantile regression (QR), and run of depression (ROD) phenotypes. The RMSE phenotype was calculated by fitting a simple linear regression of FI on age within animal and taking the square root of the average squared residual from the model. To calculate the QR phenotype, a 5% quantile regression was fitted across all daily feed intake records to set a lower bound for off-feed days. The QR phenotype was quantified as the proportion of days within animal that fell below the overall quantile regression line. The ROD phenotype was calculated by fitting a within animal linear regression line, flagging extended consecutive stretches of days below that regression line (i.e. a ROD), and calculating the percentage of days that fall within a ROD for each animal. Heritability estimates for the FI resilience phenotypes ranged from 0.10±0.04 to 0.17±0.04. Genetic correlations of the FI resilience phenotypes with mortality and treatment rate ranged from 0.66±20 to 0.94±0.20. This research demonstrates that resilience phenotypes can effectively quantify resilience and can add value to a breeding program to improve resilience to many stressors. Funded by Genome Canada, Genome Alberta, and PigGen Canada.


2000 ◽  
Vol 43 (5) ◽  
pp. 451-462
Author(s):  
S. Karsten ◽  
R. Röhe ◽  
V. Schulze ◽  
H. Looft ◽  
E. Kalm

Abstract. Title of the paper. Genetic association between individual feed intake during Performance test and reproductions traits in pigs The present study deals with the estimation of genetic correlations between Performance test traits measured in boars and reproduction traits of their offspring (sibs) of two purebred lines. Performance traits were individual feed intake (FI) recorded by electronic feeder, feed conversion ratio (FCR), average daily gain (ADG) and backfat thickness (BF). Reproduction traits were number of total piglets born (NBT) and born alive (NBA) Data of 4869 young boars, Performance tested between April 1992 and May 1997 and data of 9710 primiparous sows farrowed between June 1994 to November 1998, were observed. Heritabilities of Performance traits recorded on Station were in line 03 (line 04) h2 = 0.24 (0.33), 0.33 (0.33), 0.23 (0.32) and 0.47 (0.53) for FI, ADG FCR and BF, respectively. Heritabilities of reproduction traits such as NBT, NBA were in line 03 (line 04) h2 = 0 05 (0.08) and 0.05 (0.06), respectively. Genetic correlation between individual feed intake and reproduction traits ranged between rg = 0.12 and 0.27. Undesirable genetic correlations were found between reproduction traits and feed efficiency (rg = 0.13 to 0.44), backfat thickness (rg = 0.07 to 0.25) and partly average daily gain (rg = −010 to 0.09). Line 04 showed lowest magnitude of feed intake and highest genetic antagonism between production and reproduction traits. It is suggested that feed intake capacity is a limiting factor for reproduction in line 04 and genetic antagonism between production and reproduction traits increases with reduction in feed intake.


2021 ◽  
Author(s):  
Jian Cheng ◽  
Austin M. Putz ◽  
John C. S. Harding ◽  
Michael K. Dyck ◽  
Frederic Fortin ◽  
...  

Abstract BackgroundThe pork industry faces unprecedented challenges from disease, which increases cost of production and use of antibiotics, and reduces production efficiency, carcass quality, and animal wellbeing. One solution is to improve the overall resilience of pigs to a broad array of common diseases through genetic selection. Behavioral changes in eating and drinking are usually the very first clinical signs when animals are exposed to stressors such as disease. Changes in feed and water intake behaviors in diseased pigs may reflect the way they cope with the challenge and, thus, could be used as indicator traits to selection of disease resilience. The objectives of this study were to estimate genetic parameters of feed and water intake and behavior traits for wean-to-finish pigs in a natural polymicrobial disease challenge model, estimate genetic correlations of feed and water intake and behavior traits with growth rate and clinical disease traits, and to develop indicator traits for selection of disease resilience.ResultsIn general, water intake traits had moderate to high estimates of heritability, especially for average daily water dispensed, duration, and number of visits (0.44 to 0.58). Similar estimates were observed for corresponding feed intake traits (0.35 to 0.51). Most genetic correlation estimates among drinking traits were moderate to high (0.30 to 0.92) and higher than among feeding traits (0 to 0.11). Compared to other water intake traits, water intake duration and number of visits had relatively stronger negative genetic correlation estimates with treatment rate and mortality, especially across the challenge nursery and finisher (-0.39 and -0.45 for treatment rate; -0.20 and -0.19 for mortality). ConclusionMost water and feed intake traits under severe disease challenge had moderate to high estimates of heritability, especially for feed or water intake duration and number of visits. Phenotypic and genetic correlations among feed intake traits under disease were generally low but water intake traits showed high correlations with each other. Water intake duration and number of visits are potential indicator traits to select for disease resilience because of their high heritability and had moderate genetic correlations with treatment and mortality rates under severe disease.


Animals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 705 ◽  
Author(s):  
Chia ◽  
Tanga ◽  
Osuga ◽  
Alaru ◽  
Mwangi ◽  
...  

Pig production is one of the fastest growing livestock sectors. Development of this sector is hampered by rapidly increasing costs of fishmeal (FM), which is a common protein source in animal feeds. Here, we explored the potential of substituting FM with black soldier fly larval meal (BSFLM) on growth and blood parameters of pigs as well as economic aspects. At weaning, 40 hybrid pigs, i.e., crossbreeds of purebred Large White and Landrace were randomly assigned to five iso-nitrogenous and iso-energetic dietary treatments: Control (0% BSFLM and 100% FM (T0)), and FM replaced at 25% (T25), 50% (T50), 75% (T75) and 100% (T100) with BSFLM. Average daily feed intake (ADFI), average daily gain (ADG), body weight gain (BWG) and feed conversion ratio (FCR) were calculated for the whole trial. Hematological and serum biochemical parameters, the cost–benefit ratio (CBR) and return on investment (RoI) were evaluated. No significant effect of diet type was observed on feed intake and daily weight gain. Red or white blood cell indices did not differ among diets. Pigs fed T25, T75 and T100, had lower platelet counts compared to T0 and T50. Dietary inclusion of BSFLM did not affect blood total cholesterol, triglycerides, low-density lipoprotein and high-density lipoprotein. CBR and RoI were similar for the various diets. In conclusion, BSFLM is a suitable and cost-effective alternative to fishmeal in feed for growing pigs.


2017 ◽  
Vol 57 (4) ◽  
pp. 627 ◽  
Author(s):  
J. I. Velazco ◽  
R. M. Herd ◽  
D. J. Cottle ◽  
R. S. Hegarty

As daily methane production (DMP; g CH4/day) is strongly correlated with dry matter intake (DMI), the breeding of cattle that require less feed to achieve a desired rate of average daily gain (ADG) by selection for a low residual feed intake (RFI) can be expected to reduce DMP and also emission intensity (EI; g CH4/kg ADG). An experiment was conducted to compare DMP and EI of Angus cattle genetically divergent for RFI and 400-day weight (400dWT). In a 6-week grazing study, 64 yearling-age cattle (30 steers, 34 heifers) were grazed on temperate pastures, with heifers and steers grazing separate paddocks. Liveweight (LW) was monitored weekly and DMP of individual cattle was measured by a GreenFeed emission monitoring unit in each paddock. Thirty-nine of the possible 64 animals had emission data recorded for 15 or more days, and only data for these animals were analysed. For these cattle, regression against their mid-parent estimated breeding value (EBV) for post-weaning RFI (RFI-EBV) showed that a lower RFI-EBV was associated with higher LW at the start of experiment. Predicted dry matter intake (pDMI), predicted DMP (pDMP) and measured DMP (mDMP) were all negatively correlated with RFI-EBV (P < 0.05), whereas ADG, EI, predicted CH4 yield (pMY; g CH4/kg DMI) were not correlated with RFI-EBV (P > 0.1). Daily CH4 production was positively correlated with animal LW and ADG (P < 0.05). The associations between ADG and its dependent traits EI and pMY and predicted feed conversion ratio (kg pDMI/kg ADG) were strongly negative (r = –0.82, –0.57 and –0.85, P < 0.001) implying that faster daily growth by cattle was accompanied by lower EI, MY and feed conversion ratio. These results show that cattle genetically divergent for RFI do not necessarily differ in ADG, EI or pMY on pasture and that, if heavier, cattle with lower RFI-EBV can actually have higher DMP while grazing moderate quality pastures.


2014 ◽  
Vol 54 (3) ◽  
pp. 319 ◽  
Author(s):  
Ronald E. Newman ◽  
Jeffery A. Downing ◽  
Peter C. Thomson ◽  
Cherie L. Collins ◽  
David J. Henman ◽  
...  

Three studies investigated the effect of feeding strategy on production performance and endocrine status of growing pigs. For Experiment 1, 20 entire male pigs (70.0 ± 4.6 kg) were allocated randomly to individual pens in one of four climate-controlled rooms. Pigs were fed for 23 days either ad libitum or entrained to feed bi-phasically for two 90-min periods. For Experiment 2, 20 entire male pigs (41.2 ± 3.5 kg) were housed as per Experiment 1. Pigs were fed for 49 days either ad libitum or fed bi-phasically for two 60-min periods. For Experiment 3, 100 female pigs (66.1 ± 3.5 kg) were randomly allocated to individual pens within a commercial piggery and fed for 42 days either ad libitum or bi-phasically for two 60-min periods. Ear vein catheters were inserted into 10 pigs from each group and hourly blood samples were collected for 24 h in Experiments 1 and 2 and for 11 h in Experiment 3. Plasma insulin, non-esterified fatty acid and glucose concentrations were determined in Experiments 1 and 2, and glucose and insulin concentrations in Experiment 3. Feed intake and performance were recorded in all experiments and carcass composition was assessed by computed tomography for Experiment 2. There were no differences in final liveweight between the two treatment groups for all experiments. Pigs fed for two 90-min periods (Experiment 1) showed no difference in feed intake when compared with feeding ad libitum. Pigs in Experiment 2 fed for two 60-min intervals consumed 2.49 kg/pig.day compared with those fed ad libitum that consumed 2.68 kg/day (P = 0.057). In Experiment 3, pigs fed twice daily consumed 2.82 kg/pig.day compared with 2.91 kg/pig.day in ad libitum-fed pigs (P = 0.051). Bi-phasic fed pigs in Experiment 2 had improved (P < 0.05) feed conversion efficiency compared with pigs fed ad libitum. For all experiments, there was no difference in plasma glucose concentrations between the two treatments. In all three experiments, the circulating insulin concentrations for pigs fed ad libitum remained at a constant level throughout the sampling period. However, plasma insulin concentrations for the bi-phasic fed pigs significantly increased ~1 h after both feeding periods during all three experiments. Insulin secretion of pigs fed for two 90-min periods differed from that of pigs fed for two 60-min periods. Plasma insulin concentration increased five-fold following feeding for 60 min, compared with that in pigs fed for 90 min, which increased two-fold. Bi-phasic-fed pigs from Experiment 2 had reduced (P < 0.05) total carcass fat and significantly increased muscle when compared with pigs fed ad libitum. The data showed that feeding pigs at two succinct periods aligned insulin secretion to the time of feeding. Pigs fed for 60 min, unlike those fed for 90-min intervals, had reduced feed intake in comparison to those fed ad libitum. This may suggest that the duration of the feeding bout is important for this response and this may in turn influence both energy balance and the way energy is partitioned.


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