Ghader Manafiazar | University of Alberta (original) (raw)
Papers by Ghader Manafiazar
Canadian Journal of Animal Science, 2018
This study evaluated the effects of three genomic indicators of heterosis on female fertility and... more This study evaluated the effects of three genomic indicators of heterosis on female fertility and lifetime productivity, and quantified changes over 11 production cycles in a crossbred cow herd. Pedigree-based breed composition (pBC) was determined and used to calculate retained heterozygosity for 412 replacement heifers born from 2004 to 2014 at the Lacombe Research and Development Centre (AB, Canada). Heifers were followed as cows over 1050 mating opportunities, 11 production cycles, and five parities. Heifers and their sires (51) were genotyped and these genotypes were used to predict each animal’s genomic breed composition (gBC) and three genomic indicators of heterosis: (1) retained heterozygosity (RHETg), (2) heterozygous proportion (H), and (3) retained heterosis (RHg). Correlations between pedigree and genomic breed fractions for Angus, Hereford, and Charolais were high (rp = 0.74–0.94; P
Journal of Central European Agriculture, 2019
The native goat breeds could be better managed and their genetic diversity to be conserved throug... more The native goat breeds could be better managed and their genetic diversity to be conserved through identification of population genetic structure. Total of 299 animals from six goat breeds, which are major native breeds of Iran, were used to study their genetic structure and understand relationship among the breeds using SSR markers on 13 microsatellite loci. The breeds were selected from different geographic regions of Iran. The results indicated that there is high genetic diversity at the population level (HS of 0.78) and at the species level (HT of 0.86). The level of inbreeding was low across the breeds and even genetic diversion was observed among them, indicating a low level of gene flow at the regional scale. Some level of admixtures was observed among breeds, which supported by clustering of the breeds based on their geographic origin. Analysis of the population genetic structure indicated that all breeds are grouped into four clusters. The assignment accuracy per locus ranged from 40.1% (BM4621) to 66.9% (oarJMP23). The assignment power of microsatellites based on the Bayesian method had positive correlation with the number of alleles and gene differentiation coefficient (Gst) per locus. In conclusion, this study provided a genetic profile for the conservation and improvement and origin of the studied breeds.
Canadian Journal of Animal Science, 2017
Data from a total of 4,842 animals were used to test whether the regular DMI data collection and ... more Data from a total of 4,842 animals were used to test whether the regular DMI data collection and RFI estimation period could be decreased. Eighty-three shortened test periods were compared to the regular test period, and the results showed that the DMI data collection period could be decreased to 42 days without significantly compromising accuracy of feed efficiency testing. Competency of the selected shorter period (42 d with 30-42 d of valid feed intake days) to predict regular test period DMI (84 d with 60-84 d of valid feed intake days) was tested using a set of agreements criteria. The results showed that the selected shorter period can be used to accurately and precisely predict regular test DMI. The selected shorter test period combined with regular body weight measurements were used to estimate RFI adjusted for backfat (RFI fat). Assessment of agreement between estimated values for RFI fat showed that a shorter DMI test could be used to predict RFI fat with only 7% outside the range prediction. It is concluded that shortening the feed intake period to 42 d from 84 days could substantially increase power-of-the-test for experiments that target feed intake or efficiency and reduce perhead cost with the current infrastructure.
Canadian Journal of Animal Science, 2016
The purpose of this study was to determine the repeatability of methane (CH 4) and carbon dioxide... more The purpose of this study was to determine the repeatability of methane (CH 4) and carbon dioxide (CO 2) emissions from beef cattle using GreenFeed emissions monitoring (GEM) system and as affected by sampling frequency and measurement periods. Twenty-eight crossbred replacement beef heifers were monitored using the GEM system over 59 d to collect their CH 4 and CO 2 emissions data. Heifers' feed intake was recorded by eight automated feeding stations. The standardized dry matter intake (SDMI), CH 4 and CO 2 emission and yield (g kg −1 SDMI) were averaged over 1, 3, 7, and 14 d periods. On average, animals emitted 204.7 g d −1 (SD = 36 g d −1) and 6408 g d −1 (SD = 780 g d −1) of CH 4 and CO 2 , respectively. Between-animal coefficients of variation for all variables decreased with an increasing averaging period (from 1 to 14 d). The coefficient of determination (R 2) between CH 4 emission and SDMI was increased from 0.25 to 0.73 as averaging period increased from 1 to 14 d. Similarly, the R 2 between CO 2 emission and SDMI increased from 0.39 to 0.79 as averaging period increased from 1 to 14 d. It was determined that averaging over 7 to 14 d with minimum of 20 spot samples was needed to produce repeatable and reliable averaged CH 4 and CO 2 emissions and correlated with SDMI.
Small Ruminant Research, 2016
Italian Journal of Animal Science, 2010
In order to determine of ruminal nutrient degradability of some feeds (wheat straw, alfalfa hay, ... more In order to determine of ruminal nutrient degradability of some feeds (wheat straw, alfalfa hay, barley grain, concentrates) and total mixed rations, about 3 g of DM equivalent of samples were weighed in sealed nylon bags (6-cm × 7.5-cm) that were incubated in the rumen of three ruminally fistulated buffalo steers (BW= 389.6 ± 7.5 kg) that fed corn silage and concentrates at maintenance level in a ratio of about 65: 35 (DM basis) according to the following periods 0, 3, 6, 12, 18, 24, 36, 48, 72 and 96 h. Using Cr-mordanated NDF of alfalfa as a single dose marker, ruminal kinetic of digestion were measured. Mean ruminal particulate passage rate (%/h), particulate passage rate in lower compartment on gastrointestinal tract (%/h), ruminal mean retention time (h), mean retention time in lower compartment (h), total mean retention time (h), and delay time of marker were 0.0378, 0.0489, 26.46, 20.45, 56.565 and 9.654, respectively. Dry matter, crud protein, and NDF had similar trend on kinetic of digestion. Barely grain and concentrate had higher degradable fraction (a, b and a + b), rate and extent of degradation and effective degradability. In contrast, forages had lower parameters than others feeds. Barely had the highest degradable DM, NDF, and CP, wheat straw had the lowest degradable DM, NDF, and CP. The lag time of DM and NDF were lowest and highest in barely and wheat straw, respectively. In addition, barely had the highest effective degradability, but wheat straw had the lowest one. It is generally considered that rumen turnover time is slower in buffaloes than in cattle may be a more appropriate indicator of potential ferment ability of feeds in the former species.
Journal of Animal and Veterinary Advances
One deterministic model that show flock dairy cattle agreement with fixing prices milk team in Ir... more One deterministic model that show flock dairy cattle agreement with fixing prices milk team in Iran and parities of economic efficiency in milk product and fat percent and milk protein percent and long life of flock in two tendency (profit maximizing and cost minimizing), 3 kind of limitation in team dimensions (number of cattle, input and milk product) and 2 kind of fix flock cost (independent of number of cattle and to be changeable of all cost per cattle) were calculated. Effects of different system limitation for economic efficiency were considered. In maximizing profit tendency, trait long life of flock is less changeable than other traits. In tendency minimizing cost and to be changeable of all costs per cattle efficiency of economic qualities is independent kind of limitation in dimensions and system. So, if in calculation of economic efficiency tendency choice to be minimizing cost and cost to allow for changeable per cattle economic efficiency product, probable maximizing c...
Canadian Journal of Animal Science, 2015
3 grazing tame pasture, with no negative impact on their body weight, back-fat thickness, and 46 ... more 3 grazing tame pasture, with no negative impact on their body weight, back-fat thickness, and 46 ADG compared with their high RFI fat herd mates. 47 48 49 Abbreviations: ADF, acid detergent fiber; ADG, average daily gain; BW, body weight; CP, 50 crude protein; CWD, cell wall digestibility; DM, dry matter; DMI, dry matter intake; IVTD, in 51 vitro true digestibility; ME, metabolizable energy; MIDWT, mid-point weight; NDF, neutral 52 detergent fiber; r g , genetic correlation; r p, phenotypic correlation; RFI, Residual feed intake; 53 RFI fat , residual feed intake adjusted for end of test backfat thickness; RG fat , residual gain 54 adjusted for end of test backfat thickness; RIG fat , residual intake and gain adjusted for end of test 55 backfat thickness; TDN, total digestible nutrients. 56 57 Feed is the largest variable cost and an important determinant of profitability in the beef 58 production system [Alberta Agriculture and Rural Development (AARD) 2005; Ramsey et al. 59 2005]. In North America, 55 to 75% of the total costs of calf-to-beef production systems are 60 associated with feed costs [National Research Council (NRC) 2000; AARD 2005]. About two-61 thirds of the feed energy is required for body maintenance (Ferrell and Jenkins 1985; Montano-62 Bermudez et al. 1990), and considerable animal-to-animal variation, independent of body size 63 and growth, exists in maintenance requirements of cattle (Herd and Bishop 2000; Arthur et al. 64 2001a, b; Nkrumah et al. 2006; Crowley et al. 2010). Thus, improving feed efficiency through 65 genetic selection holds significant opportunity for the beef industry. 66 Improving feed conversion ratio by selection for traditional efficiency measures such as 67 increased growth rate may not improve cow feed efficiency because of drawbacks associated 68 with increased maintenance requirements (Van der Werf 2004; Crews 2005). As a result, 69 residual feed intake also referred to as net feed efficiency, was originally proposed by Byerly 70 (1941) and defined by Koch et al. (1963) as the difference between an animal's actual feed 71 intake and its expected feed requirement for maintenance of body size and production level. Low 72 RFI in growing animals represents individuals with lower feed intake at equal body size and 73 growth, with lower maintenance energy requirements and thus greater efficiency. More recently, 74 RFI values have been adjusted for body fatness (RFI fat ), thus attempting to render RFI 75 independent of carcass fatness in slaughter cattle and later maturity or fattening in replacement 76 heifers and bulls Crews 2005).
Milk Production - An Up-to-Date Overview of Animal Nutrition, Management and Health, 2012
Schematic concept of residual feed intake (RFI). Two animals which have the same BW and ADG, are ... more Schematic concept of residual feed intake (RFI). Two animals which have the same BW and ADG, are expected to consume the same amount of feed but in reality cow A consumes more than expected while cow B consumes less, so cow B is more efficient than A. Figure 1. Schematic concept of residual feed intake (RFI). Two animals which have the same BW and ADG, are expected to consume the same amount of feed but in reality cow A consumes more than expected while cow B consumes less, so cow B is more efficient than A. ... Energy transformation ...
Spanish Journal of Agricultural Research, 2014
PLoS ONE, 2014
Genetic correlations between performance traits with meat quality and carcass traits were estimat... more Genetic correlations between performance traits with meat quality and carcass traits were estimated on 6,408 commercial crossbred pigs with performance traits recorded in production systems with 2,100 of them having meat quality and carcass measurements. Significant fixed effects (company, sex and batch), covariates (birth weight, cold carcass weight, and age), random effects (additive, litter and maternal) were fitted in the statistical models. A series of pairwise bivariate analyses were implemented in ASREML to estimate heritability, phenotypic, and genetic correlations between performance traits (n = 9) with meat quality (n = 25) and carcass (n = 19) traits. The animals had a pedigree compromised of 9,439 animals over 15 generations. Performance traits had low-to-moderate heritabilities (6SE), ranged from 0.0760.13 to 0.4560.07 for weaning weight, and ultrasound backfat depth, respectively. Genetic correlations between performance and carcass traits were moderate to high. The results indicate that: (a) selection for birth weight may increase drip loss, lightness of longissimus dorsi, and gluteus medius muscles but may reduce fat depth; (b) selection for nursery weight can be valuable for increasing both quantity and quality traits; (c) selection for increased daily gain may increase the carcass weight and most of the primal cuts. These findings suggest that deterioration of pork quality may have occurred over many generations through the selection for less backfat thickness, and feed efficiency, but selection for growth had no adverse effects on pork quality. Low-to-moderate heritabilities for performance traits indicate that they could be improved using traditional selection or genomic selection. The estimated genetic parameters for performance, carcass and meat quality traits may be incorporated into the breeding programs that emphasize product quality in these Canadian swine populations.
Small Ruminant Research, 2005
The growth performance and carcass traits of two fat-tailed breeds (Chaal and Zandi) and their cr... more The growth performance and carcass traits of two fat-tailed breeds (Chaal and Zandi) and their crosses with rams of a tailed breed (Zel) were compared. After weaning, the growth and feed consumption of male and female lambs fattened for 114 days were recorded. A total of 45 male and female lambs were slaughtered and the left side of the carcasses were cut into six pieces, and the lean meat, bone, subcutaneous and intermuscular fat were determined. Average daily gain and feed conversion ratio in crossbred lambs improved, but the differences with pure lambs were not significant. The average weight of shoulder, brisket and loin were higher in crossbred than pure breed lambs (P < 0.01). The percentage of protein in the carcass of Zel × Zandi lambs was significantly higher than Zandi lambs. The smaller size and lower weight of fat-tail in crossbred lambs were compensated by higher percentage of subcutaneous, intermuscular and internal fat. The fat-tailed breeds provided good quality lean meat in terms of lower percentage of intermuscular fat.
Journal of Animal Science, 2014
Pork quality and carcass characteristics are now being integrated into swine breeding objectives ... more Pork quality and carcass characteristics are now being integrated into swine breeding objectives because of their economic value. Understanding the genetic basis for these traits is necessary for this to be accomplished. The objective of this study was to estimate phenotypic and genetic parameters for carcass and meat quality traits in 2 Canadian swine populations. Data from a genomic selection study aimed at improving meat quality with a mating system involving hybrid Landrace × Large White and Duroc pigs were used to estimate heritabilities and phenotypic and genetic correlations among them. Data on 2,100 commercial crossbred pigs for meat quality and carcass traits were recorded with pedigrees compromising 9,439 animals over 15 generations. Significant fixed effects (company, sex, and slaughter batch), covariates (cold carcass weight and slaughter age), and random additive and common litter effects were fitted in the models. A series of pairwise bivariate analyses were implemented in ASReml to estimate phenotypic and genetic parameters. Heritability estimates (±SE) for carcass traits were moderate to high and ranged from 0.22 ± 0.08 for longissimus dorsi muscle area to 0.63 ± 0.04 for trimmed ham weight, except for firmness, which was low. Heritability estimates (±SE) for meat quality traits varied from 0.10 ± 0.04 to 0.39 ± 0.06 for the Minolta b* of ham quadriceps femoris muscle and shear force, respectively. Generally, most of the genetic correlations were significant (P < 0.05) and ranged from low (0.18 ± 0.07) to high (-0.97 ± 0.35). There were high negative genetic correlations between drip loss with pH and shear force and a positive correlation with cooking loss. Genetic correlations between carcass weight (both hot and cold) with carcass marbling were highly positive. It was concluded that selection for increasing primal and subprimal cut weights with better pork quality may be possible. Furthermore, the use of pH is confirmed as an indicator for pork water-holding capacity and cooking loss. The heritabilities of carcass and pork quality traits indicated that they can be improved using traditional breeding methods and genomic selection, respectively. The estimated genetic parameters for carcass and meat quality traits can be incorporated into the breeding programs that emphasize product quality in these Canadian swine populations.
Italian Journal of Animal Science, 2010
Reproduction efficiency is one of the most important factors for productivity and profitably of d... more Reproduction efficiency is one of the most important factors for productivity and profitably of dairy animals. Late or delayed oestrus in buffalo heifers is one of the major factors limiting its overall productive and reproductive performance. Feeding and general management have been reported to improve reproduction efficiency of buffaloes. Reproduction is partly affected by nutrition supplementation. Thus the objective of this study was to investigate the effect of supplemented ration on some reproductive traits in Azeri buffaloes. One hundred and twenty female buffalo calves with 8 months age were randomly divided into four groups (30 calves in each group). Calves received I) traditional ration (TR) II) TR plus 0.5 kg concentrate III) TR plus 1 kg concentrate IV) TR plus 1.5 kg concentrates till the age at first estrous. There was no difference between initial weights of calves before the treatments. The reproductive traits considered were age at first oestrus, weight at first oestrus, number of oestruses before gestation, age at gestation, age at calving. Although there were no significant differences between the all studied traits among treatments, the supplementation in Group 4 improved the traits somehow; in particular, treatment 4 decreased by 70 days the age at calving compared to treatment 1. This indicates that the W. Azerbaijan buffaloes suffer a nutritional deficiency in their lifetime and that quality /quantity supplementation of ration can improve their reproductive performance.
Italian Journal of Animal Science, 2010
Italian Journal of Animal Science, 2010
Iran has 500thousand heads buffalo that 80percent of them distributed in North and North West of ... more Iran has 500thousand heads buffalo that 80percent of them distributed in North and North West of Iran and they reared as multi purpose animals providing milk and meat. Farmer believe that buffalo milk had the best quality but because of huge and large head and skin buffaloes carcass isn't suitable that governmental programmer pay a low facilities to buffalo fattener in comparison the cattle fattener thus the objective of this investigation was to the Comparison carcass traits of buffalo, native and Native cows* Holstein (NH) male calves that mostly fattened in this region. Eighty head claves (six heads of each treat) with average 160 kg body weight (BW) were fattened till the 300 kg. Ration and other environmental factors were the same. Three heads of each group's according Iranian Standards slaughtered at abattoir. The slaughter weight, hot carcass weight, and the individual weights of the different slaughter by-products and organs were measured. The carcasses were chilled at 5 o C for 24 h. One side of each carcass was cutting into wholesales cuts. Traits included Hot and cold carcass weight, bone, internal fat, meat, cut ability fat, dressing percent, wholesales cuts weight and percent. Wholesales cuts include neck, shoulder, loin, rib and flank and leg weight and percent. The results showed that there were not significant differences between hot and cold carcass weigh, meat, bone and cut ability fat percent. There were significant differences on internal fat, dressing percent and leg (P<0.05). The lowest and highest values for internal fat were observed buffalo and native carcass, respectively. In conclusion because of low internal fat deposition and high valuable wholesales cuts percent may buffalo carcass composition had a better quality in comparison cattle and fattening of buffalo is economically.
Italian Journal of Animal Science, 2010
This experimental study was carried out to determine the efficacy of rumen cannulation technique ... more This experimental study was carried out to determine the efficacy of rumen cannulation technique on some rumen metabolic parameters in buffaloes. Four healthy male River (Azari) buffaloes with no previous history of gastrointestinal dysfunction were chosen. There are several surgical techniques that can be used for rumen cannulation in farm animals, including buffaloes. This procedure was performed in a modified two-stage technique. In the first stage, the dorso -lateral portion of the dorsal sac of the rumen wall was sutured to the skin incision in the left para lumbar fossa region. In the second -stage, after six days left, the exposed rumen wall area was incised and the cannula was inserted and fixed manually in the rumenal opening incision site. In order to evaluate the efficacy of rumen cannulation technique on some rumen metabolic parameters, this study was achieved with different levels of NDF, and chewing behavior and their relationship with ruminal acidity, was measured in a change over design. Two diets with 2 levels of NDF were used as treatments. First and second diets had 52 and 47 % of NDF, respectively. Animals fed ad libitum at 09:00 and 21:00. There were no significant differences between chemical composition, particles distribution, geometric mean, its standard deviation and physically effective factor (pef) of diets, dry matter intake (kg/d) and nutrients intake (NDF, ADF, NFC and crude protein) and their digestibility. Increasing NFC reduced ruminal pH at 0.5, 1.0, 4.5, 6.0 9.0 and 10.0 h post feeding. In addition, there were not significant differences on eating time, rumination time and total chewing activity between diets. All data obtained in this study were in normal range may indicating the efficacy of this cannulation method. More investigation should be done to determine the efficacy and comparison of the other surgical rumen cannulation techniques on Azari buffaloes of Iran.
Italian Journal of Animal Science, 2010
This experimental study was carried out to determine the efficacy of rumen cannulation technique ... more This experimental study was carried out to determine the efficacy of rumen cannulation technique on some rumen metabolic parameters in buffaloes. Four healthy male River (Azari) buffaloes with no previous history of gastrointestinal dysfunction were chosen. There are several surgical techniques that can be used for rumen cannulation in farm animals, including buffaloes. This procedure was performed in a modified two-stage technique. In the first stage, the dorso -lateral portion of the dorsal sac of the rumen wall was sutured to the skin incision in the left para lumbar fossa region. In the second -stage, after six days left, the exposed rumen wall area was incised and the cannula was inserted and fixed manually in the rumenal opening incision site. In order to evaluate the efficacy of rumen cannulation technique on some rumen metabolic parameters, this study was achieved with different levels of NDF, and chewing behavior and their relationship with ruminal acidity, was measured in a change over design. Two diets with 2 levels of NDF were used as treatments. First and second diets had 52 and 47 % of NDF, respectively. Animals fed ad libitum at 09:00 and 21:00. There were no significant differences between chemical composition, particles distribution, geometric mean, its standard deviation and physically effective factor (pef) of diets, dry matter intake (kg/d) and nutrients intake (NDF, ADF, NFC and crude protein) and their digestibility. Increasing NFC reduced ruminal pH at 0.5, 1.0, 4.5, 6.0 9.0 and 10.0 h post feeding. In addition, there were not significant differences on eating time, rumination time and total chewing activity between diets. All data obtained in this study were in normal range may indicating the efficacy of this cannulation method. More investigation should be done to determine the efficacy and comparison of the other surgical rumen cannulation techniques on Azari buffaloes of Iran.
Italian Journal of Animal Science, 2010
The buffalo is a native animal of Iran and there were 500,000 buffaloes in Iran that over 80 per ... more The buffalo is a native animal of Iran and there were 500,000 buffaloes in Iran that over 80 per cent of its population concentrated in the north and north-west (Azerbaijan province) and 18 per cent in the south (Khuzestan province) of the country. Buffaloes reread in rural condition as multi purpose animals in Khuzestan. For mating, farmer use owns herd sire also artificial insemination is limited in the rural condition that may be inbred animals so affect the production performance. The aim of this investigation was estimate the inbreeding coefficient and its affect on some production performance. Data of 200 herds were used from the record sheets of herds under recording program of Animal Breeding Center during period 1990 to 2002 in the Khuzestan province. These results showed mostly herds only one sir and rarely two sires have been used. Inbreeding coefficient was 25 percent in some progeny and high-inbred buffaloes had a low performance. According to results of this study it could be concluded that farmers to avoid inbreeding should use other herd sire and artificial insemination also practical recording scheme and genetically selection to genetic improvement should be included in buffaloes of Iran.
Canadian Journal of Animal Science, 2018
This study evaluated the effects of three genomic indicators of heterosis on female fertility and... more This study evaluated the effects of three genomic indicators of heterosis on female fertility and lifetime productivity, and quantified changes over 11 production cycles in a crossbred cow herd. Pedigree-based breed composition (pBC) was determined and used to calculate retained heterozygosity for 412 replacement heifers born from 2004 to 2014 at the Lacombe Research and Development Centre (AB, Canada). Heifers were followed as cows over 1050 mating opportunities, 11 production cycles, and five parities. Heifers and their sires (51) were genotyped and these genotypes were used to predict each animal’s genomic breed composition (gBC) and three genomic indicators of heterosis: (1) retained heterozygosity (RHETg), (2) heterozygous proportion (H), and (3) retained heterosis (RHg). Correlations between pedigree and genomic breed fractions for Angus, Hereford, and Charolais were high (rp = 0.74–0.94; P
Journal of Central European Agriculture, 2019
The native goat breeds could be better managed and their genetic diversity to be conserved throug... more The native goat breeds could be better managed and their genetic diversity to be conserved through identification of population genetic structure. Total of 299 animals from six goat breeds, which are major native breeds of Iran, were used to study their genetic structure and understand relationship among the breeds using SSR markers on 13 microsatellite loci. The breeds were selected from different geographic regions of Iran. The results indicated that there is high genetic diversity at the population level (HS of 0.78) and at the species level (HT of 0.86). The level of inbreeding was low across the breeds and even genetic diversion was observed among them, indicating a low level of gene flow at the regional scale. Some level of admixtures was observed among breeds, which supported by clustering of the breeds based on their geographic origin. Analysis of the population genetic structure indicated that all breeds are grouped into four clusters. The assignment accuracy per locus ranged from 40.1% (BM4621) to 66.9% (oarJMP23). The assignment power of microsatellites based on the Bayesian method had positive correlation with the number of alleles and gene differentiation coefficient (Gst) per locus. In conclusion, this study provided a genetic profile for the conservation and improvement and origin of the studied breeds.
Canadian Journal of Animal Science, 2017
Data from a total of 4,842 animals were used to test whether the regular DMI data collection and ... more Data from a total of 4,842 animals were used to test whether the regular DMI data collection and RFI estimation period could be decreased. Eighty-three shortened test periods were compared to the regular test period, and the results showed that the DMI data collection period could be decreased to 42 days without significantly compromising accuracy of feed efficiency testing. Competency of the selected shorter period (42 d with 30-42 d of valid feed intake days) to predict regular test period DMI (84 d with 60-84 d of valid feed intake days) was tested using a set of agreements criteria. The results showed that the selected shorter period can be used to accurately and precisely predict regular test DMI. The selected shorter test period combined with regular body weight measurements were used to estimate RFI adjusted for backfat (RFI fat). Assessment of agreement between estimated values for RFI fat showed that a shorter DMI test could be used to predict RFI fat with only 7% outside the range prediction. It is concluded that shortening the feed intake period to 42 d from 84 days could substantially increase power-of-the-test for experiments that target feed intake or efficiency and reduce perhead cost with the current infrastructure.
Canadian Journal of Animal Science, 2016
The purpose of this study was to determine the repeatability of methane (CH 4) and carbon dioxide... more The purpose of this study was to determine the repeatability of methane (CH 4) and carbon dioxide (CO 2) emissions from beef cattle using GreenFeed emissions monitoring (GEM) system and as affected by sampling frequency and measurement periods. Twenty-eight crossbred replacement beef heifers were monitored using the GEM system over 59 d to collect their CH 4 and CO 2 emissions data. Heifers' feed intake was recorded by eight automated feeding stations. The standardized dry matter intake (SDMI), CH 4 and CO 2 emission and yield (g kg −1 SDMI) were averaged over 1, 3, 7, and 14 d periods. On average, animals emitted 204.7 g d −1 (SD = 36 g d −1) and 6408 g d −1 (SD = 780 g d −1) of CH 4 and CO 2 , respectively. Between-animal coefficients of variation for all variables decreased with an increasing averaging period (from 1 to 14 d). The coefficient of determination (R 2) between CH 4 emission and SDMI was increased from 0.25 to 0.73 as averaging period increased from 1 to 14 d. Similarly, the R 2 between CO 2 emission and SDMI increased from 0.39 to 0.79 as averaging period increased from 1 to 14 d. It was determined that averaging over 7 to 14 d with minimum of 20 spot samples was needed to produce repeatable and reliable averaged CH 4 and CO 2 emissions and correlated with SDMI.
Small Ruminant Research, 2016
Italian Journal of Animal Science, 2010
In order to determine of ruminal nutrient degradability of some feeds (wheat straw, alfalfa hay, ... more In order to determine of ruminal nutrient degradability of some feeds (wheat straw, alfalfa hay, barley grain, concentrates) and total mixed rations, about 3 g of DM equivalent of samples were weighed in sealed nylon bags (6-cm × 7.5-cm) that were incubated in the rumen of three ruminally fistulated buffalo steers (BW= 389.6 ± 7.5 kg) that fed corn silage and concentrates at maintenance level in a ratio of about 65: 35 (DM basis) according to the following periods 0, 3, 6, 12, 18, 24, 36, 48, 72 and 96 h. Using Cr-mordanated NDF of alfalfa as a single dose marker, ruminal kinetic of digestion were measured. Mean ruminal particulate passage rate (%/h), particulate passage rate in lower compartment on gastrointestinal tract (%/h), ruminal mean retention time (h), mean retention time in lower compartment (h), total mean retention time (h), and delay time of marker were 0.0378, 0.0489, 26.46, 20.45, 56.565 and 9.654, respectively. Dry matter, crud protein, and NDF had similar trend on kinetic of digestion. Barely grain and concentrate had higher degradable fraction (a, b and a + b), rate and extent of degradation and effective degradability. In contrast, forages had lower parameters than others feeds. Barely had the highest degradable DM, NDF, and CP, wheat straw had the lowest degradable DM, NDF, and CP. The lag time of DM and NDF were lowest and highest in barely and wheat straw, respectively. In addition, barely had the highest effective degradability, but wheat straw had the lowest one. It is generally considered that rumen turnover time is slower in buffaloes than in cattle may be a more appropriate indicator of potential ferment ability of feeds in the former species.
Journal of Animal and Veterinary Advances
One deterministic model that show flock dairy cattle agreement with fixing prices milk team in Ir... more One deterministic model that show flock dairy cattle agreement with fixing prices milk team in Iran and parities of economic efficiency in milk product and fat percent and milk protein percent and long life of flock in two tendency (profit maximizing and cost minimizing), 3 kind of limitation in team dimensions (number of cattle, input and milk product) and 2 kind of fix flock cost (independent of number of cattle and to be changeable of all cost per cattle) were calculated. Effects of different system limitation for economic efficiency were considered. In maximizing profit tendency, trait long life of flock is less changeable than other traits. In tendency minimizing cost and to be changeable of all costs per cattle efficiency of economic qualities is independent kind of limitation in dimensions and system. So, if in calculation of economic efficiency tendency choice to be minimizing cost and cost to allow for changeable per cattle economic efficiency product, probable maximizing c...
Canadian Journal of Animal Science, 2015
3 grazing tame pasture, with no negative impact on their body weight, back-fat thickness, and 46 ... more 3 grazing tame pasture, with no negative impact on their body weight, back-fat thickness, and 46 ADG compared with their high RFI fat herd mates. 47 48 49 Abbreviations: ADF, acid detergent fiber; ADG, average daily gain; BW, body weight; CP, 50 crude protein; CWD, cell wall digestibility; DM, dry matter; DMI, dry matter intake; IVTD, in 51 vitro true digestibility; ME, metabolizable energy; MIDWT, mid-point weight; NDF, neutral 52 detergent fiber; r g , genetic correlation; r p, phenotypic correlation; RFI, Residual feed intake; 53 RFI fat , residual feed intake adjusted for end of test backfat thickness; RG fat , residual gain 54 adjusted for end of test backfat thickness; RIG fat , residual intake and gain adjusted for end of test 55 backfat thickness; TDN, total digestible nutrients. 56 57 Feed is the largest variable cost and an important determinant of profitability in the beef 58 production system [Alberta Agriculture and Rural Development (AARD) 2005; Ramsey et al. 59 2005]. In North America, 55 to 75% of the total costs of calf-to-beef production systems are 60 associated with feed costs [National Research Council (NRC) 2000; AARD 2005]. About two-61 thirds of the feed energy is required for body maintenance (Ferrell and Jenkins 1985; Montano-62 Bermudez et al. 1990), and considerable animal-to-animal variation, independent of body size 63 and growth, exists in maintenance requirements of cattle (Herd and Bishop 2000; Arthur et al. 64 2001a, b; Nkrumah et al. 2006; Crowley et al. 2010). Thus, improving feed efficiency through 65 genetic selection holds significant opportunity for the beef industry. 66 Improving feed conversion ratio by selection for traditional efficiency measures such as 67 increased growth rate may not improve cow feed efficiency because of drawbacks associated 68 with increased maintenance requirements (Van der Werf 2004; Crews 2005). As a result, 69 residual feed intake also referred to as net feed efficiency, was originally proposed by Byerly 70 (1941) and defined by Koch et al. (1963) as the difference between an animal's actual feed 71 intake and its expected feed requirement for maintenance of body size and production level. Low 72 RFI in growing animals represents individuals with lower feed intake at equal body size and 73 growth, with lower maintenance energy requirements and thus greater efficiency. More recently, 74 RFI values have been adjusted for body fatness (RFI fat ), thus attempting to render RFI 75 independent of carcass fatness in slaughter cattle and later maturity or fattening in replacement 76 heifers and bulls Crews 2005).
Milk Production - An Up-to-Date Overview of Animal Nutrition, Management and Health, 2012
Schematic concept of residual feed intake (RFI). Two animals which have the same BW and ADG, are ... more Schematic concept of residual feed intake (RFI). Two animals which have the same BW and ADG, are expected to consume the same amount of feed but in reality cow A consumes more than expected while cow B consumes less, so cow B is more efficient than A. Figure 1. Schematic concept of residual feed intake (RFI). Two animals which have the same BW and ADG, are expected to consume the same amount of feed but in reality cow A consumes more than expected while cow B consumes less, so cow B is more efficient than A. ... Energy transformation ...
Spanish Journal of Agricultural Research, 2014
PLoS ONE, 2014
Genetic correlations between performance traits with meat quality and carcass traits were estimat... more Genetic correlations between performance traits with meat quality and carcass traits were estimated on 6,408 commercial crossbred pigs with performance traits recorded in production systems with 2,100 of them having meat quality and carcass measurements. Significant fixed effects (company, sex and batch), covariates (birth weight, cold carcass weight, and age), random effects (additive, litter and maternal) were fitted in the statistical models. A series of pairwise bivariate analyses were implemented in ASREML to estimate heritability, phenotypic, and genetic correlations between performance traits (n = 9) with meat quality (n = 25) and carcass (n = 19) traits. The animals had a pedigree compromised of 9,439 animals over 15 generations. Performance traits had low-to-moderate heritabilities (6SE), ranged from 0.0760.13 to 0.4560.07 for weaning weight, and ultrasound backfat depth, respectively. Genetic correlations between performance and carcass traits were moderate to high. The results indicate that: (a) selection for birth weight may increase drip loss, lightness of longissimus dorsi, and gluteus medius muscles but may reduce fat depth; (b) selection for nursery weight can be valuable for increasing both quantity and quality traits; (c) selection for increased daily gain may increase the carcass weight and most of the primal cuts. These findings suggest that deterioration of pork quality may have occurred over many generations through the selection for less backfat thickness, and feed efficiency, but selection for growth had no adverse effects on pork quality. Low-to-moderate heritabilities for performance traits indicate that they could be improved using traditional selection or genomic selection. The estimated genetic parameters for performance, carcass and meat quality traits may be incorporated into the breeding programs that emphasize product quality in these Canadian swine populations.
Small Ruminant Research, 2005
The growth performance and carcass traits of two fat-tailed breeds (Chaal and Zandi) and their cr... more The growth performance and carcass traits of two fat-tailed breeds (Chaal and Zandi) and their crosses with rams of a tailed breed (Zel) were compared. After weaning, the growth and feed consumption of male and female lambs fattened for 114 days were recorded. A total of 45 male and female lambs were slaughtered and the left side of the carcasses were cut into six pieces, and the lean meat, bone, subcutaneous and intermuscular fat were determined. Average daily gain and feed conversion ratio in crossbred lambs improved, but the differences with pure lambs were not significant. The average weight of shoulder, brisket and loin were higher in crossbred than pure breed lambs (P < 0.01). The percentage of protein in the carcass of Zel × Zandi lambs was significantly higher than Zandi lambs. The smaller size and lower weight of fat-tail in crossbred lambs were compensated by higher percentage of subcutaneous, intermuscular and internal fat. The fat-tailed breeds provided good quality lean meat in terms of lower percentage of intermuscular fat.
Journal of Animal Science, 2014
Pork quality and carcass characteristics are now being integrated into swine breeding objectives ... more Pork quality and carcass characteristics are now being integrated into swine breeding objectives because of their economic value. Understanding the genetic basis for these traits is necessary for this to be accomplished. The objective of this study was to estimate phenotypic and genetic parameters for carcass and meat quality traits in 2 Canadian swine populations. Data from a genomic selection study aimed at improving meat quality with a mating system involving hybrid Landrace × Large White and Duroc pigs were used to estimate heritabilities and phenotypic and genetic correlations among them. Data on 2,100 commercial crossbred pigs for meat quality and carcass traits were recorded with pedigrees compromising 9,439 animals over 15 generations. Significant fixed effects (company, sex, and slaughter batch), covariates (cold carcass weight and slaughter age), and random additive and common litter effects were fitted in the models. A series of pairwise bivariate analyses were implemented in ASReml to estimate phenotypic and genetic parameters. Heritability estimates (±SE) for carcass traits were moderate to high and ranged from 0.22 ± 0.08 for longissimus dorsi muscle area to 0.63 ± 0.04 for trimmed ham weight, except for firmness, which was low. Heritability estimates (±SE) for meat quality traits varied from 0.10 ± 0.04 to 0.39 ± 0.06 for the Minolta b* of ham quadriceps femoris muscle and shear force, respectively. Generally, most of the genetic correlations were significant (P < 0.05) and ranged from low (0.18 ± 0.07) to high (-0.97 ± 0.35). There were high negative genetic correlations between drip loss with pH and shear force and a positive correlation with cooking loss. Genetic correlations between carcass weight (both hot and cold) with carcass marbling were highly positive. It was concluded that selection for increasing primal and subprimal cut weights with better pork quality may be possible. Furthermore, the use of pH is confirmed as an indicator for pork water-holding capacity and cooking loss. The heritabilities of carcass and pork quality traits indicated that they can be improved using traditional breeding methods and genomic selection, respectively. The estimated genetic parameters for carcass and meat quality traits can be incorporated into the breeding programs that emphasize product quality in these Canadian swine populations.
Italian Journal of Animal Science, 2010
Reproduction efficiency is one of the most important factors for productivity and profitably of d... more Reproduction efficiency is one of the most important factors for productivity and profitably of dairy animals. Late or delayed oestrus in buffalo heifers is one of the major factors limiting its overall productive and reproductive performance. Feeding and general management have been reported to improve reproduction efficiency of buffaloes. Reproduction is partly affected by nutrition supplementation. Thus the objective of this study was to investigate the effect of supplemented ration on some reproductive traits in Azeri buffaloes. One hundred and twenty female buffalo calves with 8 months age were randomly divided into four groups (30 calves in each group). Calves received I) traditional ration (TR) II) TR plus 0.5 kg concentrate III) TR plus 1 kg concentrate IV) TR plus 1.5 kg concentrates till the age at first estrous. There was no difference between initial weights of calves before the treatments. The reproductive traits considered were age at first oestrus, weight at first oestrus, number of oestruses before gestation, age at gestation, age at calving. Although there were no significant differences between the all studied traits among treatments, the supplementation in Group 4 improved the traits somehow; in particular, treatment 4 decreased by 70 days the age at calving compared to treatment 1. This indicates that the W. Azerbaijan buffaloes suffer a nutritional deficiency in their lifetime and that quality /quantity supplementation of ration can improve their reproductive performance.
Italian Journal of Animal Science, 2010
Italian Journal of Animal Science, 2010
Iran has 500thousand heads buffalo that 80percent of them distributed in North and North West of ... more Iran has 500thousand heads buffalo that 80percent of them distributed in North and North West of Iran and they reared as multi purpose animals providing milk and meat. Farmer believe that buffalo milk had the best quality but because of huge and large head and skin buffaloes carcass isn't suitable that governmental programmer pay a low facilities to buffalo fattener in comparison the cattle fattener thus the objective of this investigation was to the Comparison carcass traits of buffalo, native and Native cows* Holstein (NH) male calves that mostly fattened in this region. Eighty head claves (six heads of each treat) with average 160 kg body weight (BW) were fattened till the 300 kg. Ration and other environmental factors were the same. Three heads of each group's according Iranian Standards slaughtered at abattoir. The slaughter weight, hot carcass weight, and the individual weights of the different slaughter by-products and organs were measured. The carcasses were chilled at 5 o C for 24 h. One side of each carcass was cutting into wholesales cuts. Traits included Hot and cold carcass weight, bone, internal fat, meat, cut ability fat, dressing percent, wholesales cuts weight and percent. Wholesales cuts include neck, shoulder, loin, rib and flank and leg weight and percent. The results showed that there were not significant differences between hot and cold carcass weigh, meat, bone and cut ability fat percent. There were significant differences on internal fat, dressing percent and leg (P<0.05). The lowest and highest values for internal fat were observed buffalo and native carcass, respectively. In conclusion because of low internal fat deposition and high valuable wholesales cuts percent may buffalo carcass composition had a better quality in comparison cattle and fattening of buffalo is economically.
Italian Journal of Animal Science, 2010
This experimental study was carried out to determine the efficacy of rumen cannulation technique ... more This experimental study was carried out to determine the efficacy of rumen cannulation technique on some rumen metabolic parameters in buffaloes. Four healthy male River (Azari) buffaloes with no previous history of gastrointestinal dysfunction were chosen. There are several surgical techniques that can be used for rumen cannulation in farm animals, including buffaloes. This procedure was performed in a modified two-stage technique. In the first stage, the dorso -lateral portion of the dorsal sac of the rumen wall was sutured to the skin incision in the left para lumbar fossa region. In the second -stage, after six days left, the exposed rumen wall area was incised and the cannula was inserted and fixed manually in the rumenal opening incision site. In order to evaluate the efficacy of rumen cannulation technique on some rumen metabolic parameters, this study was achieved with different levels of NDF, and chewing behavior and their relationship with ruminal acidity, was measured in a change over design. Two diets with 2 levels of NDF were used as treatments. First and second diets had 52 and 47 % of NDF, respectively. Animals fed ad libitum at 09:00 and 21:00. There were no significant differences between chemical composition, particles distribution, geometric mean, its standard deviation and physically effective factor (pef) of diets, dry matter intake (kg/d) and nutrients intake (NDF, ADF, NFC and crude protein) and their digestibility. Increasing NFC reduced ruminal pH at 0.5, 1.0, 4.5, 6.0 9.0 and 10.0 h post feeding. In addition, there were not significant differences on eating time, rumination time and total chewing activity between diets. All data obtained in this study were in normal range may indicating the efficacy of this cannulation method. More investigation should be done to determine the efficacy and comparison of the other surgical rumen cannulation techniques on Azari buffaloes of Iran.
Italian Journal of Animal Science, 2010
This experimental study was carried out to determine the efficacy of rumen cannulation technique ... more This experimental study was carried out to determine the efficacy of rumen cannulation technique on some rumen metabolic parameters in buffaloes. Four healthy male River (Azari) buffaloes with no previous history of gastrointestinal dysfunction were chosen. There are several surgical techniques that can be used for rumen cannulation in farm animals, including buffaloes. This procedure was performed in a modified two-stage technique. In the first stage, the dorso -lateral portion of the dorsal sac of the rumen wall was sutured to the skin incision in the left para lumbar fossa region. In the second -stage, after six days left, the exposed rumen wall area was incised and the cannula was inserted and fixed manually in the rumenal opening incision site. In order to evaluate the efficacy of rumen cannulation technique on some rumen metabolic parameters, this study was achieved with different levels of NDF, and chewing behavior and their relationship with ruminal acidity, was measured in a change over design. Two diets with 2 levels of NDF were used as treatments. First and second diets had 52 and 47 % of NDF, respectively. Animals fed ad libitum at 09:00 and 21:00. There were no significant differences between chemical composition, particles distribution, geometric mean, its standard deviation and physically effective factor (pef) of diets, dry matter intake (kg/d) and nutrients intake (NDF, ADF, NFC and crude protein) and their digestibility. Increasing NFC reduced ruminal pH at 0.5, 1.0, 4.5, 6.0 9.0 and 10.0 h post feeding. In addition, there were not significant differences on eating time, rumination time and total chewing activity between diets. All data obtained in this study were in normal range may indicating the efficacy of this cannulation method. More investigation should be done to determine the efficacy and comparison of the other surgical rumen cannulation techniques on Azari buffaloes of Iran.
Italian Journal of Animal Science, 2010
The buffalo is a native animal of Iran and there were 500,000 buffaloes in Iran that over 80 per ... more The buffalo is a native animal of Iran and there were 500,000 buffaloes in Iran that over 80 per cent of its population concentrated in the north and north-west (Azerbaijan province) and 18 per cent in the south (Khuzestan province) of the country. Buffaloes reread in rural condition as multi purpose animals in Khuzestan. For mating, farmer use owns herd sire also artificial insemination is limited in the rural condition that may be inbred animals so affect the production performance. The aim of this investigation was estimate the inbreeding coefficient and its affect on some production performance. Data of 200 herds were used from the record sheets of herds under recording program of Animal Breeding Center during period 1990 to 2002 in the Khuzestan province. These results showed mostly herds only one sir and rarely two sires have been used. Inbreeding coefficient was 25 percent in some progeny and high-inbred buffaloes had a low performance. According to results of this study it could be concluded that farmers to avoid inbreeding should use other herd sire and artificial insemination also practical recording scheme and genetically selection to genetic improvement should be included in buffaloes of Iran.