Pub Date : 2023-08-02DOI: 10.3389/fanim.2023.1202270
Logan R. Kilburn-Kappeler, C. Aldrich
There has been increased interest among pet owners to feed vegetarian diets to their pets. However, the primary protein sources used in pet food today are animal based, warranting a need to evaluate novel plant-based ingredients to meet the protein demand. Corn fermented protein (CFP), a coproduct from ethanol production, may provide a plant-based alternative protein source for pet food. Therefore, the objectives of this study were to determine the effects of increasing levels of CFP on extrusion processing, stool quality, apparent total tract digestibility, and palatability in dog diets. Four extruded diets were fed to 12 adult beagle dogs in a replicated 4 × 4 Latin square design. The control diet contained 15% soybean meal (0C) and CFP was exchanged at either 5%, 10%, or 15% of soybean meal (5C, 10C, and 15C, respectively). Dogs were fed each dietary treatment for 9 days of adaption followed by 5 days of total fecal collection. Feces were scored on a 1–5 scale, with 1 representing liquid diarrhea and 5 representing hard pellet-like. Titanium dioxide (0.4%) was added to all diets as an external marker to estimate digestibility. Data were analyzed using orthogonal contrasts in SAS (version 9.4; SAS Institute, Inc., Cary, NC, USA). Dry bulk density of kibble decreased (P < 0.05), whereas kibble toughness increased (P < 0.05) with CFP inclusion. Fecal dry matter, dry fecal output, and defecations per day increased (P < 0.05) when dogs were fed increased levels of CFP. Dry matter and crude protein digestibility of CFP treatments were comparable (P > 0.05) to 0C. There was a decrease (P < 0.05) in organic matter, crude fat, gross energy, and total dietary fiber digestibility in the CFP treatments compared with 0C. A cubic relationship (P < 0.05) was observed in the digestibility of all nutrients except crude fat, indicating that 10C resulted in the lowest digestibility. For the palatability assessment, dogs had no preference when comparing the 5C treatment with the 0C treatment. Even with the differences in dietary treatments, inclusion of CFP at 5%, 10%, and 15% still resulted in acceptable processing parameters, kibble characteristics, and utilization when fed to dogs.
{"title":"Evaluation of graded levels of corn fermented protein on extrusion processing and diet utilization in healthy adult dogs","authors":"Logan R. Kilburn-Kappeler, C. Aldrich","doi":"10.3389/fanim.2023.1202270","DOIUrl":"https://doi.org/10.3389/fanim.2023.1202270","url":null,"abstract":"There has been increased interest among pet owners to feed vegetarian diets to their pets. However, the primary protein sources used in pet food today are animal based, warranting a need to evaluate novel plant-based ingredients to meet the protein demand. Corn fermented protein (CFP), a coproduct from ethanol production, may provide a plant-based alternative protein source for pet food. Therefore, the objectives of this study were to determine the effects of increasing levels of CFP on extrusion processing, stool quality, apparent total tract digestibility, and palatability in dog diets. Four extruded diets were fed to 12 adult beagle dogs in a replicated 4 × 4 Latin square design. The control diet contained 15% soybean meal (0C) and CFP was exchanged at either 5%, 10%, or 15% of soybean meal (5C, 10C, and 15C, respectively). Dogs were fed each dietary treatment for 9 days of adaption followed by 5 days of total fecal collection. Feces were scored on a 1–5 scale, with 1 representing liquid diarrhea and 5 representing hard pellet-like. Titanium dioxide (0.4%) was added to all diets as an external marker to estimate digestibility. Data were analyzed using orthogonal contrasts in SAS (version 9.4; SAS Institute, Inc., Cary, NC, USA). Dry bulk density of kibble decreased (P < 0.05), whereas kibble toughness increased (P < 0.05) with CFP inclusion. Fecal dry matter, dry fecal output, and defecations per day increased (P < 0.05) when dogs were fed increased levels of CFP. Dry matter and crude protein digestibility of CFP treatments were comparable (P > 0.05) to 0C. There was a decrease (P < 0.05) in organic matter, crude fat, gross energy, and total dietary fiber digestibility in the CFP treatments compared with 0C. A cubic relationship (P < 0.05) was observed in the digestibility of all nutrients except crude fat, indicating that 10C resulted in the lowest digestibility. For the palatability assessment, dogs had no preference when comparing the 5C treatment with the 0C treatment. Even with the differences in dietary treatments, inclusion of CFP at 5%, 10%, and 15% still resulted in acceptable processing parameters, kibble characteristics, and utilization when fed to dogs.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69759867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-01DOI: 10.3389/fanim.2023.1170377
T. Davis, Katherine E. Amirault, J. Stewart, C. B. Gleason, N. Dias, C. Timlin, Z. Seekford, A. Ealy, V. Mercadante, R. White
Proper production of steroid hormones, such as progesterone (P4), is essential for maintenance of pregnancy. Provision of gluconeogenic substrates from the diet may alter postabsorptive energy supplies and associated hormone signaling in a manner supportive of elevating P4 concentrations. Crossbred Angus heifers (n=27) were balanced for pre-trial bodyweight (BW) and body condition score (BCS), then assigned to isoenergetic diets leveraging starch (ES) or fat (EF) as the primary source of energy (45.7% starch vs 11.5% fat). The heifers were placed on the assigned diets 8 days prior to the initiation of estrous synchronization and continued the diets through the second pregnancy diagnosis, 52 days after the initial insemination. On day 28 post-breeding, pregnancy status was diagnosed via ultrasonography. Measurements of follicle size and number were collected via rectal palpation and ultrasonography on days −10, −8, −4, and day 0 relative to breeding. Blood samples were collected on days −10, 1 through 7, 10, 14, 18, 21, 24, and 28 to analyze plasma for P4 concentrations and placental-associated glycoprotein (PAG) concentrations. Data were analyzed using a linear mixed effects model with a fixed effect for treatment and a random effect for pen. Observations collected over time were analyzed using a repeated measures approach with fixed effects for treatment, time, initial condition, and a random effect for pen. Interactions between treatment and pregnancy status were also tested for PAG and P4 concentrations. No treatment differences were observed in final BCS (P=0.12) and total dry matter intake (DMI; P=0.51), though heifers on the ES treatment tended to reach an increased BW (P=0.10). Although heifers fed ES diets had numerically higher conception rates compared to heifers fed EF diets (71.4% vs. 66.7%), there was no statistically significant difference. Furthermore, there were no significant differences observed among diets in terms of pregnancy outcomes, follicle size, or number. A treatment by pregnancy status interaction was detected for both PAG and P4 concentrations. These results suggest that short-term dietary starch supplementation provided around the time of breeding can result in shifts to reproductive hormone abundance that may be conducive for pregnancy establishment.
{"title":"Effect of dietary energy source on pregnancy rates and reproductive physiology of pastured beef heifers","authors":"T. Davis, Katherine E. Amirault, J. Stewart, C. B. Gleason, N. Dias, C. Timlin, Z. Seekford, A. Ealy, V. Mercadante, R. White","doi":"10.3389/fanim.2023.1170377","DOIUrl":"https://doi.org/10.3389/fanim.2023.1170377","url":null,"abstract":"Proper production of steroid hormones, such as progesterone (P4), is essential for maintenance of pregnancy. Provision of gluconeogenic substrates from the diet may alter postabsorptive energy supplies and associated hormone signaling in a manner supportive of elevating P4 concentrations. Crossbred Angus heifers (n=27) were balanced for pre-trial bodyweight (BW) and body condition score (BCS), then assigned to isoenergetic diets leveraging starch (ES) or fat (EF) as the primary source of energy (45.7% starch vs 11.5% fat). The heifers were placed on the assigned diets 8 days prior to the initiation of estrous synchronization and continued the diets through the second pregnancy diagnosis, 52 days after the initial insemination. On day 28 post-breeding, pregnancy status was diagnosed via ultrasonography. Measurements of follicle size and number were collected via rectal palpation and ultrasonography on days −10, −8, −4, and day 0 relative to breeding. Blood samples were collected on days −10, 1 through 7, 10, 14, 18, 21, 24, and 28 to analyze plasma for P4 concentrations and placental-associated glycoprotein (PAG) concentrations. Data were analyzed using a linear mixed effects model with a fixed effect for treatment and a random effect for pen. Observations collected over time were analyzed using a repeated measures approach with fixed effects for treatment, time, initial condition, and a random effect for pen. Interactions between treatment and pregnancy status were also tested for PAG and P4 concentrations. No treatment differences were observed in final BCS (P=0.12) and total dry matter intake (DMI; P=0.51), though heifers on the ES treatment tended to reach an increased BW (P=0.10). Although heifers fed ES diets had numerically higher conception rates compared to heifers fed EF diets (71.4% vs. 66.7%), there was no statistically significant difference. Furthermore, there were no significant differences observed among diets in terms of pregnancy outcomes, follicle size, or number. A treatment by pregnancy status interaction was detected for both PAG and P4 concentrations. These results suggest that short-term dietary starch supplementation provided around the time of breeding can result in shifts to reproductive hormone abundance that may be conducive for pregnancy establishment.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49508637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-28DOI: 10.3389/fanim.2023.1187273
Paula A. Batista Taborda, T. Valente, M. V. de Lima Carvalhal, M. V. B. da Silva, M. P. D. Paranhos da Costa
Dairy cattle with poor temperament can cause several inconveniences during milking, leading to labor difficulties, increasing the risk of accidents with animals and workers, and compromising milk yield and quality. This study aimed to estimate variance components and genetic parameters for milking temperament and its genetic correlations with milk yield in crossbred Holstein-Gyr cattle.Data were collected at three commercial farms, resulting in 5,904 records from 1,212 primiparous and multiparous lactating cows. Milking temperament (MT), measured as the milking temperament of each cow, was assessed during pre-milking udder preparation (RP) and when fitting the milking cluster (RF) by ascribing scores from 1 (cow stands quietly) to 8 (the cow is very agitated, with vigorous movements and frequent kicking). The number of steps and kicks were also recorded during pre-milking udder preparation (SRP and KRP, respectively) and when fitting the milking cluster (SRF and KRF, respectively). Milk yield (MY) was obtained from each farm database. In two of them, MY was recorded during the monthly milk control (that could or could not coincide with the date when the milking temperament assessments were carried out) and in the remaining farm, MY was recorded on the same day that the milking temperament assessments were made. Genetic parameters were estimated using the THRGibbs1f90 program applying a threshold model, which included 89 contemporary groups as fixed effects, animal age at the assessment day and the number of days in milking as covariates, and direct additive genetic and residual effects as random effects.The heritability estimates were MT= 0.14 ± 0.03 (for both, MRP and MRF), MY= 0.11 ± 0.08, SRP= 0.05 ± 0.03, KRP= 0.14 ± 0.05, SRF= 0.10 ± 0.05, and KRF= 0.32 ± 0.16. The repeatability estimates were 0.38 ± 0.05, 0.42 ± 0.02, and 0.84 ± 0.006 for MTRP, MTRF, and MY, respectively; and 0.38 ± 0.02, 0.30 ± 0.07, 0.52 ± 0.02, and 0.46 ± 0.15 for SRP, KRP, SRF, and KRF, respectively. The estimates of most genetic correlation coefficients between MTRP-MTRF were all strong and positive (MTRR-MTRF= 0.63 ± 0.10, MTRP-SRP= 0.65 ± 0.12, MTRP-KRP= 0.56 ± 0.16, MTRF-SRF= 0.77 ± 0.06, and MTRF-KRF= 0.56 ± 0.34) except for MY (MTRP-MY= 0.26 ± 0.26 and MTRF-MY= 0.21 ± 0.23). Despite the low magnitude of MT heritability, it can be included as a selection trait in the breeding program of Holsteins-Gyr cattle, although its genetic progress will be seen only in the long term. Due to the low accuracy of the genetic correlation estimates between MT and MY and the high range of the 95% posterior density interval, it cannot be affirmed by this study that the selection of a milking temperament trait will infer on milk yield. More data is therefore needed per cow and more cows need to be observed and measured to increase the reliability of the estimation of these correlations to be able to accurately interpret the results.
{"title":"Estimation of genetic parameters for milking temperament in Holstein-Gyr cows","authors":"Paula A. Batista Taborda, T. Valente, M. V. de Lima Carvalhal, M. V. B. da Silva, M. P. D. Paranhos da Costa","doi":"10.3389/fanim.2023.1187273","DOIUrl":"https://doi.org/10.3389/fanim.2023.1187273","url":null,"abstract":"Dairy cattle with poor temperament can cause several inconveniences during milking, leading to labor difficulties, increasing the risk of accidents with animals and workers, and compromising milk yield and quality. This study aimed to estimate variance components and genetic parameters for milking temperament and its genetic correlations with milk yield in crossbred Holstein-Gyr cattle.Data were collected at three commercial farms, resulting in 5,904 records from 1,212 primiparous and multiparous lactating cows. Milking temperament (MT), measured as the milking temperament of each cow, was assessed during pre-milking udder preparation (RP) and when fitting the milking cluster (RF) by ascribing scores from 1 (cow stands quietly) to 8 (the cow is very agitated, with vigorous movements and frequent kicking). The number of steps and kicks were also recorded during pre-milking udder preparation (SRP and KRP, respectively) and when fitting the milking cluster (SRF and KRF, respectively). Milk yield (MY) was obtained from each farm database. In two of them, MY was recorded during the monthly milk control (that could or could not coincide with the date when the milking temperament assessments were carried out) and in the remaining farm, MY was recorded on the same day that the milking temperament assessments were made. Genetic parameters were estimated using the THRGibbs1f90 program applying a threshold model, which included 89 contemporary groups as fixed effects, animal age at the assessment day and the number of days in milking as covariates, and direct additive genetic and residual effects as random effects.The heritability estimates were MT= 0.14 ± 0.03 (for both, MRP and MRF), MY= 0.11 ± 0.08, SRP= 0.05 ± 0.03, KRP= 0.14 ± 0.05, SRF= 0.10 ± 0.05, and KRF= 0.32 ± 0.16. The repeatability estimates were 0.38 ± 0.05, 0.42 ± 0.02, and 0.84 ± 0.006 for MTRP, MTRF, and MY, respectively; and 0.38 ± 0.02, 0.30 ± 0.07, 0.52 ± 0.02, and 0.46 ± 0.15 for SRP, KRP, SRF, and KRF, respectively. The estimates of most genetic correlation coefficients between MTRP-MTRF were all strong and positive (MTRR-MTRF= 0.63 ± 0.10, MTRP-SRP= 0.65 ± 0.12, MTRP-KRP= 0.56 ± 0.16, MTRF-SRF= 0.77 ± 0.06, and MTRF-KRF= 0.56 ± 0.34) except for MY (MTRP-MY= 0.26 ± 0.26 and MTRF-MY= 0.21 ± 0.23). Despite the low magnitude of MT heritability, it can be included as a selection trait in the breeding program of Holsteins-Gyr cattle, although its genetic progress will be seen only in the long term. Due to the low accuracy of the genetic correlation estimates between MT and MY and the high range of the 95% posterior density interval, it cannot be affirmed by this study that the selection of a milking temperament trait will infer on milk yield. More data is therefore needed per cow and more cows need to be observed and measured to increase the reliability of the estimation of these correlations to be able to accurately interpret the results.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42116269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-27DOI: 10.3389/fanim.2023.1213890
V. Lind, M. Opheim, Jorid Thorvaldsen Sandvik, I. Aasen
Macroalgae, or seaweeds, have potential for use as feed ingredients and are currently unexploited despite their content of vitamins, minerals, and protein. Brown species can accumulate iodine from seawater and there are strict limits set by the European Food Safety Authority and the FDA regarding iodine content in animal feeds. Iodine can cause health problems for consumers if over or under-consumed and its presence in end food products is strictly regulated. The aim of the present experiment was to gain knowledge on intake, distribution, and excretion of iodine in sheep supplemented with Laminaria hyperborea by-product known to contain iodine. Twelve Norwegian White Sheep male lambs, four months of age, were blocked according to initial live weight (average 37.8 kg) and randomly allocated to two diet groups. Animals were fed gras silage and concentrate, without (CTR) and including the alga by-product at a 6% inclusion rate (HYP). The iodine concentrations were 4.1 and 476 mg/kg dry matter in the CTR and HYP concentrate, respectively. After 26 days of adaptation in a barn, animals were placed in metabolism crates for three consecutive days (Period 1) with collection of rumen fluid (via esophagus), grass silage, feces, urine, and blood for iodine content. After 5 weeks in the barn, animals returned to the metabolism crates for a subsequent three consecutive day sampling and iodine analyzes (Period 2). Data were analyzed via ANOVA using a repeated measure mixed model procedure. Dry matter intake (P = 0.001) and live weight (P = 0.001) increased from Period 1 to Period 2. Lambs fed CTR had higher daily growth rate than those fed HYP (P = 0.001). Iodine intake and excretion in feces and urine increased from Period 1 to Period 2 (P < 0.001, P = 0.010, P = 0.007, respectively). Iodine excreted in feces was 37% and 67% for lambs in fed the CTR and HYP diets, respectively. None of the animals showed signs of iodine poisoning during ten the experiment. We found that most of the iodine excreted from lambs fed the HYP diet was in feces.
{"title":"Iodine intake and excretion from sheep supplemented with macroalgae (Laminaria hyperborea) by-product","authors":"V. Lind, M. Opheim, Jorid Thorvaldsen Sandvik, I. Aasen","doi":"10.3389/fanim.2023.1213890","DOIUrl":"https://doi.org/10.3389/fanim.2023.1213890","url":null,"abstract":"Macroalgae, or seaweeds, have potential for use as feed ingredients and are currently unexploited despite their content of vitamins, minerals, and protein. Brown species can accumulate iodine from seawater and there are strict limits set by the European Food Safety Authority and the FDA regarding iodine content in animal feeds. Iodine can cause health problems for consumers if over or under-consumed and its presence in end food products is strictly regulated. The aim of the present experiment was to gain knowledge on intake, distribution, and excretion of iodine in sheep supplemented with Laminaria hyperborea by-product known to contain iodine. Twelve Norwegian White Sheep male lambs, four months of age, were blocked according to initial live weight (average 37.8 kg) and randomly allocated to two diet groups. Animals were fed gras silage and concentrate, without (CTR) and including the alga by-product at a 6% inclusion rate (HYP). The iodine concentrations were 4.1 and 476 mg/kg dry matter in the CTR and HYP concentrate, respectively. After 26 days of adaptation in a barn, animals were placed in metabolism crates for three consecutive days (Period 1) with collection of rumen fluid (via esophagus), grass silage, feces, urine, and blood for iodine content. After 5 weeks in the barn, animals returned to the metabolism crates for a subsequent three consecutive day sampling and iodine analyzes (Period 2). Data were analyzed via ANOVA using a repeated measure mixed model procedure. Dry matter intake (P = 0.001) and live weight (P = 0.001) increased from Period 1 to Period 2. Lambs fed CTR had higher daily growth rate than those fed HYP (P = 0.001). Iodine intake and excretion in feces and urine increased from Period 1 to Period 2 (P < 0.001, P = 0.010, P = 0.007, respectively). Iodine excreted in feces was 37% and 67% for lambs in fed the CTR and HYP diets, respectively. None of the animals showed signs of iodine poisoning during ten the experiment. We found that most of the iodine excreted from lambs fed the HYP diet was in feces.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41786394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-27DOI: 10.3389/fanim.2023.1212194
Pauline M. Mwangi, R. Eckard, I. Gluecks, L. Merbold, D. Mulat, J. Gakige, C. Pinares-Patiño, S. Marquardt
A study was conducted with Red Maasai and Dorper lambs to evaluate the effects of infection with the gastrointestinal nematode (GIN) Haemonchus contortus on feed intake, liveweight gain (LWG), feed energy and nitrogen partitioning, and enteric methane (CH4) emissions. Six- to seven-month-old Red Maasai (n=12) and Dorper (n=12) lambs were randomly allocated to three treatments (n=8, four lambs per breed) in a 2×3 factorial cross-over study over two periods (P1 and P2) of 36 days each. The treatments consisted of three combinations of GIN infection and feeding level: Infected + ad libitum feeding (I-adlib), uninfected + ad libitum feeding (Un-adlib), and uninfected + restricted feeding (Un-restd), across the two breeds. Lambs in the I-adlib group were trickle-infected daily with 1,000 L3 stage larvae of H. contortus for four consecutive days (Days 1–4), whereas lambs in the other experimental treatments were kept GIN free. The feed intake was measured daily. Liveweight (LW), faecal egg counts (FEC), and packed cell volume (PCV) were measured on Day 1 and weekly thereafter. On Days 29–33 total faecal and urine outputs were determined in metabolic crates. The lambs were then housed in respiration chambers for three consecutive days (Days 34–36). There was a washout period of 21 days before P2 started. Uninfected lambs (Un-adlib and Un-restd) had undetectable FEC throughout the study. On Day 36, FEC did not differ between the breeds (P>0.05). Infected lambs (I-adlib) had lower PCV than uninfected (Un-adlib and Un-restd) lambs on day 36. Neither breed nor infection influenced feed and nutrient intake, but as expected, restricted-fed lambs had a lower intake (P<0.05). The LWG of Un-adlib lambs was significantly higher than that of I-adlib and Un-restd lambs (P<0.05), whereas there was no breed difference (P>0.05). Neither breed nor infection affected feed digestibility, nitrogen retention or energy metabolisability (P>0.05). However, feed restriction decreased feed intake, LWG and N retention, whereas feed digestibility and energy metabolisability were unaffected. Neither daily CH4 emissions nor yield (per unit of feed intake) were affected by experimental infection, but Un-restd lambs had lower CH4 emissions per day. Red Maasai lambs had consistently lower daily CH4 emissions and yields than Dorper (P<0.01). This study confirmed the relative resistance of indigenous sheep (Red Maasai) to H. contortus infection, but the increased CH4 emission and yield due to GIN observed in other studies was not confirmed. Further investigations are needed to test whether in environments with multiple stress factors, local or indigenous breeds or their crossbreeds with exotic breeds may be better equipped to sustain production and simultaneously have a reduced carbon footprint than purebred exotic breeds.
{"title":"Impact of Haemonchus contortus infection on feed intake, digestion, liveweight gain, and enteric methane emission from Red Maasai and Dorper sheep","authors":"Pauline M. Mwangi, R. Eckard, I. Gluecks, L. Merbold, D. Mulat, J. Gakige, C. Pinares-Patiño, S. Marquardt","doi":"10.3389/fanim.2023.1212194","DOIUrl":"https://doi.org/10.3389/fanim.2023.1212194","url":null,"abstract":"A study was conducted with Red Maasai and Dorper lambs to evaluate the effects of infection with the gastrointestinal nematode (GIN) Haemonchus contortus on feed intake, liveweight gain (LWG), feed energy and nitrogen partitioning, and enteric methane (CH4) emissions. Six- to seven-month-old Red Maasai (n=12) and Dorper (n=12) lambs were randomly allocated to three treatments (n=8, four lambs per breed) in a 2×3 factorial cross-over study over two periods (P1 and P2) of 36 days each. The treatments consisted of three combinations of GIN infection and feeding level: Infected + ad libitum feeding (I-adlib), uninfected + ad libitum feeding (Un-adlib), and uninfected + restricted feeding (Un-restd), across the two breeds. Lambs in the I-adlib group were trickle-infected daily with 1,000 L3 stage larvae of H. contortus for four consecutive days (Days 1–4), whereas lambs in the other experimental treatments were kept GIN free. The feed intake was measured daily. Liveweight (LW), faecal egg counts (FEC), and packed cell volume (PCV) were measured on Day 1 and weekly thereafter. On Days 29–33 total faecal and urine outputs were determined in metabolic crates. The lambs were then housed in respiration chambers for three consecutive days (Days 34–36). There was a washout period of 21 days before P2 started. Uninfected lambs (Un-adlib and Un-restd) had undetectable FEC throughout the study. On Day 36, FEC did not differ between the breeds (P>0.05). Infected lambs (I-adlib) had lower PCV than uninfected (Un-adlib and Un-restd) lambs on day 36. Neither breed nor infection influenced feed and nutrient intake, but as expected, restricted-fed lambs had a lower intake (P<0.05). The LWG of Un-adlib lambs was significantly higher than that of I-adlib and Un-restd lambs (P<0.05), whereas there was no breed difference (P>0.05). Neither breed nor infection affected feed digestibility, nitrogen retention or energy metabolisability (P>0.05). However, feed restriction decreased feed intake, LWG and N retention, whereas feed digestibility and energy metabolisability were unaffected. Neither daily CH4 emissions nor yield (per unit of feed intake) were affected by experimental infection, but Un-restd lambs had lower CH4 emissions per day. Red Maasai lambs had consistently lower daily CH4 emissions and yields than Dorper (P<0.01). This study confirmed the relative resistance of indigenous sheep (Red Maasai) to H. contortus infection, but the increased CH4 emission and yield due to GIN observed in other studies was not confirmed. Further investigations are needed to test whether in environments with multiple stress factors, local or indigenous breeds or their crossbreeds with exotic breeds may be better equipped to sustain production and simultaneously have a reduced carbon footprint than purebred exotic breeds.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43866079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-26DOI: 10.3389/fanim.2023.1202609
Yun Jiang, J. Chapman, B. Humphrey, Miriam García
The aim of our study was to examine the effects of an immunomodulatory feed additive (OmniGen® PRO, Phibro Animal Health, Teaneck, NJ) on ruminal fermentation homeostasis and biomarkers of stress and inflammation in dairy heifers following subacute ruminal acidosis (SARA). Holstein heifers (n = 32, 8.4 ± 0.3 months old) were allocated to receive two treatments based on body weight (BW). Treatments were (1) control (CON; n = 16, no additive) and (2) OmniGen® PRO (OGPRO, n = 16, 10 g/100 kg BW, top-dressed). From d 1 to 69, and d 72 to 77, heifers were fed ad libitum a basal TMR formulated for early lactation. On d 70, the TMR offerings were reduced by 50% based on the intake of the previous 3 days. On d 71, heifers were fed ad libitum a starch challenge diet, which was a 50/50 mix steam-rolled barley and the basal TMR on a DM basis, to induce SARA. Rumen fluid and blood samples were collected on d 66, 71, and 73. Prior to the challenge, DMI, ADG, and feed efficiency were not affected by treatment. Following the challenge, all heifers experienced a 43% decline in DMI. Rumen pH was lower on the challenge day than pre and post challenge but was unaffected by treatment. Ruminal lactate was negligible pre and post challenge but increased on the challenge day; OGPRO reduced ruminal lactate compared to CON. At all sampling points, rumen total VFA were higher in OGPRO than in CON. The challenge caused fluctuations in the acetate to propionate ratio in CON, while OGPRO heifers had less variation. Two days post challenge, OGPRO heifers tended to have lower plasma cortisol, haptoglobin, and non-esterified fatty acids (NEFA) than CON heifers. The OGPRO heifers maintained the mean corpuscular hemoglobin concentration (MCHC) and platelet concentration after the challenge, while their levels declined in CON. In this study, supplementing OGPRO to heifers fed an early lactation diet improved rumen fermentation measures prior to the starch challenge and reduced the negative effects of the challenge on rumen fermentation. In addition, following the challenge, indicators of systemic inflammation tended to be lower in heifers supplemented with OGPRO.
{"title":"Effects of OmniGen® PRO on ruminal fermentation, stress, and inflammation of Holstein cattle induced with a subacute ruminal acidosis","authors":"Yun Jiang, J. Chapman, B. Humphrey, Miriam García","doi":"10.3389/fanim.2023.1202609","DOIUrl":"https://doi.org/10.3389/fanim.2023.1202609","url":null,"abstract":"The aim of our study was to examine the effects of an immunomodulatory feed additive (OmniGen® PRO, Phibro Animal Health, Teaneck, NJ) on ruminal fermentation homeostasis and biomarkers of stress and inflammation in dairy heifers following subacute ruminal acidosis (SARA). Holstein heifers (n = 32, 8.4 ± 0.3 months old) were allocated to receive two treatments based on body weight (BW). Treatments were (1) control (CON; n = 16, no additive) and (2) OmniGen® PRO (OGPRO, n = 16, 10 g/100 kg BW, top-dressed). From d 1 to 69, and d 72 to 77, heifers were fed ad libitum a basal TMR formulated for early lactation. On d 70, the TMR offerings were reduced by 50% based on the intake of the previous 3 days. On d 71, heifers were fed ad libitum a starch challenge diet, which was a 50/50 mix steam-rolled barley and the basal TMR on a DM basis, to induce SARA. Rumen fluid and blood samples were collected on d 66, 71, and 73. Prior to the challenge, DMI, ADG, and feed efficiency were not affected by treatment. Following the challenge, all heifers experienced a 43% decline in DMI. Rumen pH was lower on the challenge day than pre and post challenge but was unaffected by treatment. Ruminal lactate was negligible pre and post challenge but increased on the challenge day; OGPRO reduced ruminal lactate compared to CON. At all sampling points, rumen total VFA were higher in OGPRO than in CON. The challenge caused fluctuations in the acetate to propionate ratio in CON, while OGPRO heifers had less variation. Two days post challenge, OGPRO heifers tended to have lower plasma cortisol, haptoglobin, and non-esterified fatty acids (NEFA) than CON heifers. The OGPRO heifers maintained the mean corpuscular hemoglobin concentration (MCHC) and platelet concentration after the challenge, while their levels declined in CON. In this study, supplementing OGPRO to heifers fed an early lactation diet improved rumen fermentation measures prior to the starch challenge and reduced the negative effects of the challenge on rumen fermentation. In addition, following the challenge, indicators of systemic inflammation tended to be lower in heifers supplemented with OGPRO.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42980896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-24DOI: 10.3389/fanim.2023.1214076
T. de Rauglaudre, Bertand Méda, S. Fontaine, W. Lambert, S. Fournel, M. Letourneau-Montminy
In broilers, the effects of crude protein (CP) reduction on animal performance are heterogeneous. This could limit the use of this strategy in commercial farms despite its potential to improve the sustainability of production. The objective of this meta-analysis was to study the effect of lowering dietary CP in fast-growing broilers with a focus on growth performance. A database was built from 29 papers published after 2016, for a total of 106 trials and 268 treatments. To be included in the database, trials had to be iso-energy and iso-lysine. Trials in which the growth rate for the control treatment was below 90% of the genetic potential of the birds were not included. The effect of the CP level was analyzed by multiple linear regression, with the trial as a random effect. A subsample of 33 trials (AACON) met the recommended amino acid (AA)-to-lysine ratios for indispensable AAs. In this subdatabase, average daily gain and average daily feed intake were maintained when dietary CP was reduced. The feed conversion ratio increased by 1.3% when CP was reduced by a one percentage point. The same CP reduction decreased daily nitrogen (N) excretion by 10.4%, whereas N retention was not affected by CP. In conclusion, respecting the ideal protein concept with the use of feed-grade AA allows for a decrease in dietary CP and N excretion with a limited impact on growth performance.
{"title":"Meta-analysis of the effect of low-protein diets on the growth performance, nitrogen excretion, and fat deposition in broilers","authors":"T. de Rauglaudre, Bertand Méda, S. Fontaine, W. Lambert, S. Fournel, M. Letourneau-Montminy","doi":"10.3389/fanim.2023.1214076","DOIUrl":"https://doi.org/10.3389/fanim.2023.1214076","url":null,"abstract":"In broilers, the effects of crude protein (CP) reduction on animal performance are heterogeneous. This could limit the use of this strategy in commercial farms despite its potential to improve the sustainability of production. The objective of this meta-analysis was to study the effect of lowering dietary CP in fast-growing broilers with a focus on growth performance. A database was built from 29 papers published after 2016, for a total of 106 trials and 268 treatments. To be included in the database, trials had to be iso-energy and iso-lysine. Trials in which the growth rate for the control treatment was below 90% of the genetic potential of the birds were not included. The effect of the CP level was analyzed by multiple linear regression, with the trial as a random effect. A subsample of 33 trials (AACON) met the recommended amino acid (AA)-to-lysine ratios for indispensable AAs. In this subdatabase, average daily gain and average daily feed intake were maintained when dietary CP was reduced. The feed conversion ratio increased by 1.3% when CP was reduced by a one percentage point. The same CP reduction decreased daily nitrogen (N) excretion by 10.4%, whereas N retention was not affected by CP. In conclusion, respecting the ideal protein concept with the use of feed-grade AA allows for a decrease in dietary CP and N excretion with a limited impact on growth performance.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48400431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-21DOI: 10.3389/fanim.2023.1228770
L. Webb, C. Verwer, E. Bokkers
An important obstacle toward sustainably produced animal-source food is the existence of so-called ‘surplus animals’, which are by-products of the production of dairy products and eggs, and ‘unwanted’ due to their perceived low value. Although this depends on the country, in Europe many surplus dairy calves are transported to veal farms to be raised for 6 months until slaughter. The aim of this article is to present ideas for alternative future systems for the dairy-veal chain, including an overview of current challenges and improvement strategies for calf welfare. This dairy-veal chain presents a number of potential concerns for calf welfare, including transportation of young animals, high risk of disease and barren housing. Many incremental changes have been suggested in past literature to lift the welfare of veal calves, including reducing transportation, transporting calves at an older age, better health screening, and pens with enrichment and bedding. The Netherlands is at the centre of the veal sector import-export flow in Europe and is one of the main veal producers in the world. The Dutch government has recently presented a report with three alternative ‘scenarios’ for the raising of these surplus dairy calves, which are expected to lead to improvements in animals welfare. The first scenario is a restriction on transport of <100km, leading to more local production of dairy-veal. The second scenario is a delay on the transportation of surplus calves from 2 weeks to 3 months of age, handing dairy farmers a much larger role in the raising of these calves. This delay would ensure that calves are more robust and less vulnerable to disease at the time that they are transported to the veal farm. The third scenario proposes an alternative system, where the veal sector is eradicated and surplus dairy calves are raised at the dairy farm of origin until slaughter. We, like others before us, question the impact of small incremental changes on calf welfare, arguing that improvements at one end could potentially lead to worsening of welfare at the other end, and prefer to focus on system changes, such as the use of dual-purpose cattle breeds. We do not however believe that system changes can be created and implemented with the sole input of animal welfare scientists. This work is hence just one piece of the puzzle towards the sustainable production of milk and meat, and more specifically the sustainable rearing of surplus calves.
{"title":"The future of surplus dairy calves – an animal welfare perspective","authors":"L. Webb, C. Verwer, E. Bokkers","doi":"10.3389/fanim.2023.1228770","DOIUrl":"https://doi.org/10.3389/fanim.2023.1228770","url":null,"abstract":"An important obstacle toward sustainably produced animal-source food is the existence of so-called ‘surplus animals’, which are by-products of the production of dairy products and eggs, and ‘unwanted’ due to their perceived low value. Although this depends on the country, in Europe many surplus dairy calves are transported to veal farms to be raised for 6 months until slaughter. The aim of this article is to present ideas for alternative future systems for the dairy-veal chain, including an overview of current challenges and improvement strategies for calf welfare. This dairy-veal chain presents a number of potential concerns for calf welfare, including transportation of young animals, high risk of disease and barren housing. Many incremental changes have been suggested in past literature to lift the welfare of veal calves, including reducing transportation, transporting calves at an older age, better health screening, and pens with enrichment and bedding. The Netherlands is at the centre of the veal sector import-export flow in Europe and is one of the main veal producers in the world. The Dutch government has recently presented a report with three alternative ‘scenarios’ for the raising of these surplus dairy calves, which are expected to lead to improvements in animals welfare. The first scenario is a restriction on transport of <100km, leading to more local production of dairy-veal. The second scenario is a delay on the transportation of surplus calves from 2 weeks to 3 months of age, handing dairy farmers a much larger role in the raising of these calves. This delay would ensure that calves are more robust and less vulnerable to disease at the time that they are transported to the veal farm. The third scenario proposes an alternative system, where the veal sector is eradicated and surplus dairy calves are raised at the dairy farm of origin until slaughter. We, like others before us, question the impact of small incremental changes on calf welfare, arguing that improvements at one end could potentially lead to worsening of welfare at the other end, and prefer to focus on system changes, such as the use of dual-purpose cattle breeds. We do not however believe that system changes can be created and implemented with the sole input of animal welfare scientists. This work is hence just one piece of the puzzle towards the sustainable production of milk and meat, and more specifically the sustainable rearing of surplus calves.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44203834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-21DOI: 10.3389/fanim.2023.1208778
D. Sacchero, Ezequiel B. Gonzalez, Julia Maurino, Miriam Lopez, Maria Victoria Cortes, Rocío Alvarez, F. Bidinost
In Argentina, mohair production is limited exclusively to the Patagonia region. This activity takes place under different biophysical conditions and with marked seasonality in the climatic conditions and productivity of natural grasslands. The present study aimed to analyze Angora goat performance, mohair production, and income in two contrasting environments of northern Patagonia.Body weight (BW), body condition score (BCS), fleece weight (FW) and mohair samples were collected between the spring of 2019 and the autumn of 2022 on farms from the East and West regions. Fiber quality analyses included mean fiber diameter (MFD), percentage of medullated fibers (MED), and kemp fibers (KMP). Analysis of variance (ANOVA) was performed and the effects considered were region, shearing season (autumn and spring) and age. The income per shearing (IPS) was estimated based on the individual data and tender prices.In general, the BW of goats in the East was between 15% and 25% higher than that of the goats in the West (p < 0.01), whereas the FW difference between regions reached 25% to 32% in mature adult goats (p < 0.01). The autumn MFD was similar between regions (p >0.05) and higher than the spring MFD (p < 0.05). The KMP content in the West was two-fold higher (p <0.01) than that in the East (1.21%). Regarding the effect of the season, KMP and MED contents were higher in autumn than in spring (p <0.01). The IPS values were lower in spring. The highest IPS value was obtained at the age of two permanent incisors. Results showed that 70 of the 100 best-ranked goats by IPS were from the East.This work offers new insights for understanding characteristics of mohair production in Argentine The results suggest that winter conditions in the West negatively impact the growth and mohair production during the spring shearing. In turn, a marked seasonality in climatic conditions and in the productivity of grasslands could explain the variability of the productive performance of goats between seasons. Efforts to improve mohair incomes should focus on producing heavier, less medullated fleeces rather than finer mohair.
{"title":"Performance of Angora goats, mohair production, and farmer income in extensive livestock systems of north Patagonia, Argentina","authors":"D. Sacchero, Ezequiel B. Gonzalez, Julia Maurino, Miriam Lopez, Maria Victoria Cortes, Rocío Alvarez, F. Bidinost","doi":"10.3389/fanim.2023.1208778","DOIUrl":"https://doi.org/10.3389/fanim.2023.1208778","url":null,"abstract":"In Argentina, mohair production is limited exclusively to the Patagonia region. This activity takes place under different biophysical conditions and with marked seasonality in the climatic conditions and productivity of natural grasslands. The present study aimed to analyze Angora goat performance, mohair production, and income in two contrasting environments of northern Patagonia.Body weight (BW), body condition score (BCS), fleece weight (FW) and mohair samples were collected between the spring of 2019 and the autumn of 2022 on farms from the East and West regions. Fiber quality analyses included mean fiber diameter (MFD), percentage of medullated fibers (MED), and kemp fibers (KMP). Analysis of variance (ANOVA) was performed and the effects considered were region, shearing season (autumn and spring) and age. The income per shearing (IPS) was estimated based on the individual data and tender prices.In general, the BW of goats in the East was between 15% and 25% higher than that of the goats in the West (p < 0.01), whereas the FW difference between regions reached 25% to 32% in mature adult goats (p < 0.01). The autumn MFD was similar between regions (p >0.05) and higher than the spring MFD (p < 0.05). The KMP content in the West was two-fold higher (p <0.01) than that in the East (1.21%). Regarding the effect of the season, KMP and MED contents were higher in autumn than in spring (p <0.01). The IPS values were lower in spring. The highest IPS value was obtained at the age of two permanent incisors. Results showed that 70 of the 100 best-ranked goats by IPS were from the East.This work offers new insights for understanding characteristics of mohair production in Argentine The results suggest that winter conditions in the West negatively impact the growth and mohair production during the spring shearing. In turn, a marked seasonality in climatic conditions and in the productivity of grasslands could explain the variability of the productive performance of goats between seasons. Efforts to improve mohair incomes should focus on producing heavier, less medullated fleeces rather than finer mohair.","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48567061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.3389/fanim.2023.1218175
P. Knap, E. Knol, A. Sørensen, A. Huisman, D. van der Spek, L. Zak, Ana Granados Chapatte, C. Lewis
Litter size in pigs has increased steadily since 1990. Because of unfavorable genetic correlations with piglet mortality, breeding goals should include survival traits next to litter size. Unbalanced breeding programs that neglect this requirement have produced increased mortality levels, attracting negative public attention. Balanced breeding does not have this disadvantage, but the general public is largely unaware of this.We present long-term time trends as realized in commercial breeding. The data includes (i) phenotypes of litter size, piglet birth weight, and piglet mortality, as used in routine breeding value estimation; and (ii) the genomic Best Linear Unbiased Prediction (gBLUP) estimated breeding values thus obtained. Piglet mortality (2001–2022) and birth weight (2009–2022) phenotypes were related to litter size by recording year. Estimated breeding values (EBVs) for the mortality traits were regressed on those for litter size by birth year (2012–2022).Average litter size is very weakly correlated to the mortality (R2 ≤ 0.06) and birth weight (0.07 ≤ R2 ≤ 0.26) traits, and those correlations are unfavorable (antagonistic) within each year. However, all traits analyzed here show favorable simultaneous phenotypic and genetic trends over time: the antagonisms are neutralized by balanced breeding. Above the annual mean litter size level, farrowing and lactation mortality rates increased with increasing litter size in every year (unfavorable), but the annual intercepts and the slopes decreased from 2001 to 2022 (favorable). Average litter birth weight decreased with litter size in every year (unfavorable), but the annual intercepts increased and the slopes decreased from 2009 to 2022 (favorable). The within-litter birth weight variation coefficient increased with litter size in every year (unfavorable), but the annual intercepts decreased from 2009 to 2022 (favorable). The proportion of low birth weights (i.e.,< 0.9 kg) for a given litter size is decreasing over time, and the critical birth weight level (below which lactation mortality increases strongly) is clearly population dependent and changes over time too.The increases in litter size and piglet survival rates due to balanced breeding policies lead to reduced total numbers of dead piglets (i.e., per country, per year) coinciding with a certain pig production volume (i.e., with a certain total number of weaned piglets).
{"title":"Genetic and phenotypic time trends of litter size, piglet mortality, and birth weight in pigs","authors":"P. Knap, E. Knol, A. Sørensen, A. Huisman, D. van der Spek, L. Zak, Ana Granados Chapatte, C. Lewis","doi":"10.3389/fanim.2023.1218175","DOIUrl":"https://doi.org/10.3389/fanim.2023.1218175","url":null,"abstract":"Litter size in pigs has increased steadily since 1990. Because of unfavorable genetic correlations with piglet mortality, breeding goals should include survival traits next to litter size. Unbalanced breeding programs that neglect this requirement have produced increased mortality levels, attracting negative public attention. Balanced breeding does not have this disadvantage, but the general public is largely unaware of this.We present long-term time trends as realized in commercial breeding. The data includes (i) phenotypes of litter size, piglet birth weight, and piglet mortality, as used in routine breeding value estimation; and (ii) the genomic Best Linear Unbiased Prediction (gBLUP) estimated breeding values thus obtained. Piglet mortality (2001–2022) and birth weight (2009–2022) phenotypes were related to litter size by recording year. Estimated breeding values (EBVs) for the mortality traits were regressed on those for litter size by birth year (2012–2022).Average litter size is very weakly correlated to the mortality (R2 ≤ 0.06) and birth weight (0.07 ≤ R2 ≤ 0.26) traits, and those correlations are unfavorable (antagonistic) within each year. However, all traits analyzed here show favorable simultaneous phenotypic and genetic trends over time: the antagonisms are neutralized by balanced breeding. Above the annual mean litter size level, farrowing and lactation mortality rates increased with increasing litter size in every year (unfavorable), but the annual intercepts and the slopes decreased from 2001 to 2022 (favorable). Average litter birth weight decreased with litter size in every year (unfavorable), but the annual intercepts increased and the slopes decreased from 2009 to 2022 (favorable). The within-litter birth weight variation coefficient increased with litter size in every year (unfavorable), but the annual intercepts decreased from 2009 to 2022 (favorable). The proportion of low birth weights (i.e.,< 0.9 kg) for a given litter size is decreasing over time, and the critical birth weight level (below which lactation mortality increases strongly) is clearly population dependent and changes over time too.The increases in litter size and piglet survival rates due to balanced breeding policies lead to reduced total numbers of dead piglets (i.e., per country, per year) coinciding with a certain pig production volume (i.e., with a certain total number of weaned piglets).","PeriodicalId":73064,"journal":{"name":"Frontiers in animal science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42904191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：