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Full-Text Articles in Animal Sciences

Responses To 19 Generations Of Litter Size Selection In The Ne Index Line. Ii. Growth And Carcass Responses Estimated In Pure Line And Crossbred Litters, D. B. Petry, J. W. Holl, R. K. Johnson Jun 2004

Responses To 19 Generations Of Litter Size Selection In The Ne Index Line. Ii. Growth And Carcass Responses Estimated In Pure Line And Crossbred Litters, D. B. Petry, J. W. Holl, R. K. Johnson

Department of Animal Science: Faculty Publications

Our objective was to estimate responses in growth and carcass traits in the NE Index line (I) that was selected for 19 generations for increased litter size. Differences between Line I and the randomly selected control line (C) were estimated in pure line litters and in F1 and three-way cross litters produced by mating I and C females with males of unrelated lines. Contrasts of means were used to estimate the genetic difference between I and C and interactions of line differences with mating type. In Exp 1, 694 gilts that were retained for breeding, including 538 I and …


Evaluation Of Procedures To Predict Fat-Free Lean In Swine Carcasses, Rodger K. Johnson, E. P. Johnson, R. Goodwin, J. W. Mabry, R. K. Miller, O. W. Robison, H. Sellers, M. D. Tokach Jan 2004

Evaluation Of Procedures To Predict Fat-Free Lean In Swine Carcasses, Rodger K. Johnson, E. P. Johnson, R. Goodwin, J. W. Mabry, R. K. Miller, O. W. Robison, H. Sellers, M. D. Tokach

Department of Animal Science: Faculty Publications

The objectives were to develop equations for predicting fat-free lean in swine carcasses and to estimate the prediction bias that was due to genetic group, sex, and dietary lysine level. Barrows and gilts (n = 1,024) from four projects conducted by the National Pork Board were evaluated by six procedures, and their carcass fat-free lean was determined. Pigs of 16 genetic groups were fed within weight groups one of four dietary regimens that differed by 0.45% in lysine content and slaughtered at weights between 89 and 163 kg. Variables in equations included carcass weight and measures of backfat depth and …


The Non-Phosphorus Effects Of Dietary Phytase In Swine And Poultry, Jason Layne Shelton Jan 2004

The Non-Phosphorus Effects Of Dietary Phytase In Swine And Poultry, Jason Layne Shelton

LSU Doctoral Dissertations

This research was conducted to determine the non-phosphorus effects of phytase in diets for swine and poultry. An experiment was conducted to determine the effect of phytase addition on energy availability and protein and fat deposition in growing pigs. Results from this experiment indicated that phytase had small positive effects on energy availability, protein deposition, and fat deposition. In this study, 23 of 29 response variables were at least numerically increased with phytase addition. Two experiments were conducted to determine the accuracy of the energy and amino acid matrix values for Natuphos 1200 in broilers from 0 to 21 or …


The National Pork Producers Council Maternal Line National Genetic Evaluation Program: A Comparison Of Six Maternal Genetic Lines For Female Productivity Measures Over Four Parities, J. S. Moeller, R. K. Johnson, J. W. Mabry, T. J. Baas, O. W. Robison Dec 2003

The National Pork Producers Council Maternal Line National Genetic Evaluation Program: A Comparison Of Six Maternal Genetic Lines For Female Productivity Measures Over Four Parities, J. S. Moeller, R. K. Johnson, J. W. Mabry, T. J. Baas, O. W. Robison

Department of Animal Science: Faculty Publications

Litter (n = 8,424) and female performance records were collected in two breed-to-wean production units in order to evaluate genetic line differences for sow longevity and maternal performance over four parities. Lines evaluated were American Diamond Genetics, Danbred North America, Dekalb-Monsanto DK44, Dekalb-Monsanto GPK347, Newsham Hybrids, and National Swine Registry. Females within a line were derived from a minimum of 65 sires, 197 dams (three dams per sire), and a maximum of three daughters per dam, except in the GPK347, which were produced using semen from 12 Nebraska Index boars mated with Dekalb-Monsanto Line 34 females. All lines expressed 100% …


Correlated Response In Placental Efficiency In Swine Selected For An Index Of Components Of Litter Size, H. Mesa, T. J. Safranski, R. K. Johnson, W. R. Lamberson Jan 2003

Correlated Response In Placental Efficiency In Swine Selected For An Index Of Components Of Litter Size, H. Mesa, T. J. Safranski, R. K. Johnson, W. R. Lamberson

Department of Animal Science: Faculty Publications

The objective of this study was to evaluate correlated response in placental efficiency to selection for components of litter size. Fourteen generations of selection had resulted in a difference between lines of three fully formed piglets at birth. Gilts from a line selected for an index of components of litter size (S, n =33) and a randomly selected control (C, n =27) were observed at farrowing. At delivery, the umbilical cord of each piglet was double tagged with identically numbered mouse ear tags to allow the piglet’s weight to be matched to the corresponding placental weight. Litter size, placental weight, …


Pig Industry Biosecurity Plan - March 2003 - Protecting The Pig Industry Is Everyone's Business, Department Of Agriculture, Western Australia Dec 2002

Pig Industry Biosecurity Plan - March 2003 - Protecting The Pig Industry Is Everyone's Business, Department Of Agriculture, Western Australia

Biosecurity published reports

Farmnote 71/2002 - Farm Biosecurity

Farmnote 43/2002 - Biosecurity in the livestock industries

StockGuard has been initiated to develop a series of biosecurity plans for the animal industries in Western Australia. Through StockGuard, representatives from the animal industries have been working with the Western Australian Department of Agriculture to identify potential threats to each of the animal industries and to develop action plans detailing how these threats can be managed.

The overall purpose of StockGuard is to identify threats to the animal industries and to develop effective ways to minimise the potential impact of these threats.

If an emergency pig …


Effects Of Dietary Energy Concentration During The Grower Period On The Accuracy Of Determining Lean Gain Potential During The Finisher Period For Pigs Selected During The Grower Period By Either A Lean Gain Formula Or By Plasma Urea Nitrogen Concentration As An Indicator Of Lean Gain, J.N. Tembei, G.W. Libal, C.R. Hamilton, D.N. Peters May 2002

Effects Of Dietary Energy Concentration During The Grower Period On The Accuracy Of Determining Lean Gain Potential During The Finisher Period For Pigs Selected During The Grower Period By Either A Lean Gain Formula Or By Plasma Urea Nitrogen Concentration As An Indicator Of Lean Gain, J.N. Tembei, G.W. Libal, C.R. Hamilton, D.N. Peters

South Dakota Swine Research Report, 2001

It is generally thought that pigs eat to satisfy their demand for energy and the amount of feed consumed is dependent on the energy density of the diet. Therefore, the amount of feed consumed when an energy-dense diet is fed will be lower than when a low energy diet is fed. Protein is the nutrient that is most frequently adjusted as energy density in the diet is changed. Energy intake influences the rates of deposition of lean and fat tissue. Nitrogen accretion is generally limited by voluntary intake of energy for pigs weighing less than 50 kg but not for …


Lean Growth And Overall Performance Of Pigs During The Finisher Phase As Affected By Lean Growth Potential Determined During The Grower Phase And Dietary Protein Level During The Finisher Phase, J.N. Tembei, G.W. Libal, D.N. Peters May 2002

Lean Growth And Overall Performance Of Pigs During The Finisher Phase As Affected By Lean Growth Potential Determined During The Grower Phase And Dietary Protein Level During The Finisher Phase, J.N. Tembei, G.W. Libal, D.N. Peters

South Dakota Swine Research Report, 2001

Selection for decreased backfat thickness and faster rate of gain has resulted in pigs with increased potential for lean gain. Although energy intake is the limiting factor for lean growth during the grower period, the underlying limiting factor to support increased protein accretion during the finishing stage seems to be lysine intake. At the finishing phase, pigs consume enough feed per day to meet their energy requirements, but protein is the most limiting nutrient Genetics and sex influence growth performance and protein accretion in finishing pigs. Pigs from different protein requirements and these differences have been associated with differences in …


Rapid Communication: Mapping Of The Beta Tropomyosin (Tpm2) Gene To Pig Chromosome 1, J. Sherwood, Daniel C. Gill, M. F. Rothschild Jan 2002

Rapid Communication: Mapping Of The Beta Tropomyosin (Tpm2) Gene To Pig Chromosome 1, J. Sherwood, Daniel C. Gill, M. F. Rothschild

Department of Animal Science: Faculty Publications

Locus. Pig Tropomyosin beta (TPM2) gene.

Genus and Species. Sus Scrofa.

Source and Description of Primers. Primers were derived by using well-conserved regions of published human and mouse sequence (GenBank accession nos. AF209746 and NM_009416). The primers were used to amplify a 1.4-kp fragment of the porcine TPM2 gene covering exons 3 through 8. The porcine cDNA sequence (GenBank accession no. AF420022) showed 95% exonic identity (325 bp) at the nucleotide level to the human skeletal muscle beta tropomyosin (GenBank accession no. X06825). Additionally, pig specific primers were designed to amplify a 246-bp piece that spans exons 3 to …


Rapid Communication: Mapping Of The Ca2+ Atpase Of Fast Twitch 1 Skeletal Muscle Sarcoplasmic Reticulum (Atp2a1) Gene To Porcine Chromosome 3, Daniel C. Ciobanu, Y. Ciobanu, M. F. Rothschild Jan 2002

Rapid Communication: Mapping Of The Ca2+ Atpase Of Fast Twitch 1 Skeletal Muscle Sarcoplasmic Reticulum (Atp2a1) Gene To Porcine Chromosome 3, Daniel C. Ciobanu, Y. Ciobanu, M. F. Rothschild

Department of Animal Science: Faculty Publications

Locus Name. Ca2+ ATPase of fast twitch 1 skeletal muscle sarcoplasmic reticulum.

Species. Sus scrofa.

Locus Symbol. ATP2A1.

Source of Primers. Two sets of PCR primers were designed based on human ATP2A1 sequences (Gen- Bank accession numbers U96773 and U96777) available in the GenBank database. Using pig genomic DNA as a template we used set A primers to amplify approximately 1,100 bp spanning exon 1 to exon 2 and set B primers to amplify 1,200 bp gene segment covering some of exon 8 through part of exon 9. These sequences were deposited in GenBank, accession number AY027797-AY027799.


Tryptophan Requirements And The Effects Of Supplemental Tryptophan On Growth Performance, Plasma Metabolites, And Meat Quality In Nursery, Growing, And Finishing Pigs, Amy Christina Guzik Jan 2002

Tryptophan Requirements And The Effects Of Supplemental Tryptophan On Growth Performance, Plasma Metabolites, And Meat Quality In Nursery, Growing, And Finishing Pigs, Amy Christina Guzik

LSU Doctoral Dissertations

This research was conducted to estimate the true digestible Trp (dTrp) requirements in nursery, growing, and late finishing pigs and the effects of supplemental Trp on physiology, behavior, and meat quality. Five experiments were conducted to estimate the dTrp requirement in nursery pigs. Using broken-line regression analysis, dTrp requirements were 0.21, 0.20, and 0.18% for Phase I (5.2 to 7.3 kg), II (6.3 to 10.2 kg), and III (10.3 to 15.7) nursery pigs. In addition, four experiments were conducted to estimate the dTrp requirements in growing and finishing pigs. Using broken-line regression analysis, the dTrp requirement of pigs weighing 30.9, …


Direct And Correlated Responses To Two-Stage Selection For Ovulation Rate And Number Of Fully Formed Pigs At Birth In Swine, A. Ruiz-Flores, R. K. Johnson Aug 2001

Direct And Correlated Responses To Two-Stage Selection For Ovulation Rate And Number Of Fully Formed Pigs At Birth In Swine, A. Ruiz-Flores, R. K. Johnson

Department of Animal Science: Faculty Publications

Our objectives were to estimate responses and genetic parameters for ovulation rate, number of fully formed pigs at birth, and other production traits following two-stage selection for increased ovulation rate and number of fully formed pigs. Eight generations of selection were practiced in each of two lines. One selection line was derived from a line that previously selected eight generations for an index to increase ovulation rate and embryonic survival (the IOL pigs). The other selection line was derived from the unselected control line of the index selection experiment (the COL pigs). The control line (C) was continued with random …


Identification Of Quantitative Trait Loci Affecting Reproduction In Pigs, J. P. Cassady, R. K. Johnson, Daniel Pomp, G. A. Rohrer, L. Dale Van Vleck, E. K. Spiegel, K. M. Gilson Feb 2001

Identification Of Quantitative Trait Loci Affecting Reproduction In Pigs, J. P. Cassady, R. K. Johnson, Daniel Pomp, G. A. Rohrer, L. Dale Van Vleck, E. K. Spiegel, K. M. Gilson

Department of Animal Science: Faculty Publications

The objective of this research was to identify chromosomal regions harboring QTL affecting reproduction in pigs. A three-generation resource population was developed by crossing low-indexing pigs from a randomly selected control line (C) with high-indexing pigs of a line selected for increased index of ovulation rate and embryonic survival (I). Differences between Lines I and C at Generation 10 were 6.7 ova and 3.3 fetuses at 50 d of gestation and 3.1 fully formed and 1.6 live pigs at birth. Phenotypic data were collected on F2 females, born in three replicates, for ovulation rate (n = 423), age at …


Candidate Gene Analysis For Loci Affecting Litter Size And Ovulation Rate In Swine, R. C. Linville, Daniel Pomp, R. K. Johnson, M. F. Rothschild Jan 2001

Candidate Gene Analysis For Loci Affecting Litter Size And Ovulation Rate In Swine, R. C. Linville, Daniel Pomp, R. K. Johnson, M. F. Rothschild

Department of Animal Science: Faculty Publications

A candidate gene approach was used to determine whether specific loci explain responses in ovulation rate (OR) and number of fully formed (FF), live (NBA), stillborn, and mummified pigs at birth observed in two lines selected for ovulation rate and litter size compared with a randomly selected control line. Line IOL was selected for an index of OR and embryonic survival for eight generations, followed by eight generations of two-stage selection for OR and litter size. Line C was selected at random for 16 generations. Line COL, derived from line C at Generation 8, underwent eight generations of two-stage selection. …


Bulletin 4435 - Exotic Diseases - Pigs, Agriculture Western Australia Sep 2000

Bulletin 4435 - Exotic Diseases - Pigs, Agriculture Western Australia

Bulletins 4000 -

An exotic disease is a disease that is not present in Australia.

If an exotic disease did occur in Australia it would cause production losses, stock deaths and stop exports of primary production. When export markets are lost they can only be re-established once it is proven the disease is eradicated


Effects Of Genetic Type And Protein Levels On Growth Of Swine, O.W. Robison, L. L. Christian, R. Goodwin, R. K. Johnson, J. W. Mabry, R. K. Miller, M. D. Tokach Aug 2000

Effects Of Genetic Type And Protein Levels On Growth Of Swine, O.W. Robison, L. L. Christian, R. Goodwin, R. K. Johnson, J. W. Mabry, R. K. Miller, M. D. Tokach

Department of Animal Science: Faculty Publications

A total of 1,588 pigs representing six genetic lines were included in this study. These lines were selected to represent a wide range of biological types for appetite, rate and composition of gain, and meat quality traits. Each line was fed four different diets differing in lysine content. Barrows and gilts were used in the experiment, and pigs were randomly assigned to come off test at one of three weights (113.6, 131.8, or 150 kg). Rates of increase in weight, backfat thickness, and longissimus muscle area were essentially linear. Genetic type and diet influenced (P < .05) rates of change in weight, backfat thickness, and longissimus muscle area and 10th rib fat depth, carcass longissimus muscle area, and dressing percentage. Genetic type × diet interactions were significant for weight change and 10th rib fat. As off-test-weight class increased fat and longissimus muscle area increased in linear fashion. In general, interactions associated with diet resulted from feeding the diet lowest in lysine. There was little evidence of genetic type × diet interactions. If those interactions that tested significant are real, they are a result of extremes in both genetic type (high fatness) and lysine level (low). Slaughtering pigs at heavier weights results in no change in rate of gain over the feeding period and linear increases in longissimus muscle area and backfat thickness.


Comparison Of Plasma Fsh Concentration In Boars And Gilts From Lines Selected For Ovulation Rate And Embryonal Survival, And Litter Size And Estimation Of (Co)Variance Components For Fsh And Ovulation Rate, R. K. Johnson, J. J. Ford May 2000

Comparison Of Plasma Fsh Concentration In Boars And Gilts From Lines Selected For Ovulation Rate And Embryonal Survival, And Litter Size And Estimation Of (Co)Variance Components For Fsh And Ovulation Rate, R. K. Johnson, J. J. Ford

Department of Animal Science: Faculty Publications

The objective of this research was to determine whether plasma concentration of FSH was genetically correlated with ovulation rate and thus was a useful trait for indirect selection. Blood samples were collected from 619 animals from five lines of pigs. Line I was selected for increased index of ovulation rate and embryonal survival, and Line C was its randomly selected control. Pigs sampled from Lines I and C were from generations 12 and 13. Pigs from three additional lines that were derived from eighth-generation pigs of Lines I and C also were used. These lines were Line C2, a randomly …


Rapid Communication: Porcine Vitamin D-25-Hydroxylase Maps To Chromosome 5, Daniel C. Ciobanu, R. K. Raven, M. F. Rothschild, N. H. Bell Jan 2000

Rapid Communication: Porcine Vitamin D-25-Hydroxylase Maps To Chromosome 5, Daniel C. Ciobanu, R. K. Raven, M. F. Rothschild, N. H. Bell

Department of Animal Science: Faculty Publications

Locus Name. Vitamin D-25-hydroxylase.

Species. Sus scrofa.

Locus Symbol. CYP25.

Source of Primers. PCR primers were designed from the published sequence for porcine vitamin D-25-hydroxylase (CYP25) cDNA (GenBank accession no. Y16417). The position of the forward and reverse primers corresponds to 506 to 530 bp and 830 to 854 bp, respectively, of the cDNA. The primer pair amplified a 348-bp fragment of the cDNA and an 862-bp fragment from the pig genomic DNA. The 862-bp fragment (Gen- Bank accession no. AF284378) was subcloned into a pNoTA vector and identity was confirmed by sequencing. Genomic sequences from 1 to 74, …


Comparison Of Plasma Fsh Concentration In Boars And Gilts From Lines Selected For Ovulation Rate And Embryonal Survival, And Litter Size And Estimation Of (Co)Variance Components For Fsh And Ovulation Rate, J. D. Cassady, Rodger K. Dennison, J. J. Ford Jan 2000

Comparison Of Plasma Fsh Concentration In Boars And Gilts From Lines Selected For Ovulation Rate And Embryonal Survival, And Litter Size And Estimation Of (Co)Variance Components For Fsh And Ovulation Rate, J. D. Cassady, Rodger K. Dennison, J. J. Ford

Department of Animal Science: Faculty Publications

The objective of this research was to determine whether plasma concentration of FSH was genetically correlated with ovulation rate and thus was a useful trait for indirect selection. Blood samples were collected from 619 animals from five lines of pigs. Line I was selected for increased index of ovulation rate and embryonal survival, and Line C was its randomly selected control. Pigs sampled from Lines I and C were from generations 12 and 13. Pigs from three additional lines that were derived from eighth-generation pigs of Lines I and C also were used. These lines were Line C2, a randomly …


Overall Animal Welfare Reviewed. Part 3: Welfare Assessment Based On Needs And Supported By Expert Opinion, M.B.M. Bracke, B. M. Spruijt, J.H.M. Metz Dec 1999

Overall Animal Welfare Reviewed. Part 3: Welfare Assessment Based On Needs And Supported By Expert Opinion, M.B.M. Bracke, B. M. Spruijt, J.H.M. Metz

Assessment of Animal Welfare Collection

Welfare concerns what matters to animals from their point of view. What matters to animals is their state of need. Satisfaction and frustration of needs are associated with emotional states, the subjective experience of which directly determines the welfare status of an animal. Because emotional states are difficult to assess, overall welfare assessment (OWA) is best approached as an assessment of needs.

For actual OW A a list of needs must be formulated. Different authors have formulated different lists. From these lists a concept need-list was constructed. For validation the needs-based approach for OWA was discussed in interviews with experts …


Responses In Ovulation Rate, Embryonal Survival, And Litter Traits In Swine To 14 Generations Of Selection To Increase Litter Size, Rodger K. Johnson, Merlyn K. Nielsen, David S. Casey Mar 1999

Responses In Ovulation Rate, Embryonal Survival, And Litter Traits In Swine To 14 Generations Of Selection To Increase Litter Size, Rodger K. Johnson, Merlyn K. Nielsen, David S. Casey

Department of Animal Science: Faculty Publications

Eleven generations of selection for increased index of ovulation rate and embryonal survival rate, followed by three generations of selection for litter size, were practiced. Laparotomy was used to count corpora lutea and fetuses at 50 d of gestation. High-indexing gilts, approximately 30%, were farrowed. Sons of dams in the upper 10% of the distribution were selected. Selection from Generations 12 to 14 was for increased number of fully formed pigs; replacements were from the largest 25% of the litters. A randomly selected control line was maintained. Responses at Generation 11 were approximately 7.4 ova and 3.8 fetuses at 50 …


Genetics Of The Interval From Weaning To Estrus In First-Litter Sows: Correlated Responses, J. Ten Napel, T. H. E. Meuwissen, R. K. Johnson, E. W. Brascamp Oct 1998

Genetics Of The Interval From Weaning To Estrus In First-Litter Sows: Correlated Responses, J. Ten Napel, T. H. E. Meuwissen, R. K. Johnson, E. W. Brascamp

Department of Animal Science: Faculty Publications

The objective of this study was to evaluate relationships between rebreeding performance and growth performance (n = 3,777 gilts) and rebreeding performance and reproductive performance (n = 2,242 sows). Our data were from a selection experiment for shorter intervals from weaning to estrus after the first parity (IWE), involving Dutch Landrace pigs, in which a selection line and a control line without selection were maintained for eight generations. Relationships were evaluated before and after transforming IWE to normal interval (NI; IWE &#; 7 d), prolonged interval (PI; IWE > 7 d), and incidence of a prolonged interval (INC). Heritabilities of NI, …


Comparison Of Observed And Simulated Grow-Finish Swine Performance Under Summer Conditions, Larry W. Turner, Thomas C. Bridges, Richard D. Coffey, Richard S. Gates, Gary R. Parker, Tami M. Brown-Brandl, Douglas G. Overhults Jul 1998

Comparison Of Observed And Simulated Grow-Finish Swine Performance Under Summer Conditions, Larry W. Turner, Thomas C. Bridges, Richard D. Coffey, Richard S. Gates, Gary R. Parker, Tami M. Brown-Brandl, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

As a part of a National Pork Producers Council educational program, our research and extension team at the University of Kentucky was linked with an independent commercial swine producer to test the NCPIG model against observed commercial on-farm data. This experience provided improved information for model development as well as increased producer insight into the data input needs and potential benefits of modeling. Detailed production information comparisons between the NCPIG model and producer data are presented for summer time conditions to assess the validity of the NCPIG model for simulation of grow-finish swine performance. Results demonstrated that the NCPIG model …


Vocal Response Of Piglets To Weaning: Effect Of Piglet Age, Daniel M. Weary, David Fraser Oct 1997

Vocal Response Of Piglets To Weaning: Effect Of Piglet Age, Daniel M. Weary, David Fraser

Ontogeny Collection

Piglets vocalize a great deal during the first few days after weaning. The aim of this experiment was to determine if the calls given by piglets vary in response to one factor thought to influence post-weaning adaptation: weaning age. In 22 litters, each containing a minimum of 9 piglets, 3 piglets were weaned under identical conditions at 3, 4 and 5 weeks of age. Vocalizations and weight gain were monitored for the week after weaning. The number of calls produced by piglets of all three ages declined from an average of 8.2 calls/min per piglet on the day of weaning …


Evidence For Quantitative Trait Loci Affecting Ovulation Rate In Pigs, Thomas A. Rathje, G. A. Rohrer, R. K. Johnson May 1997

Evidence For Quantitative Trait Loci Affecting Ovulation Rate In Pigs, Thomas A. Rathje, G. A. Rohrer, R. K. Johnson

Department of Animal Science: Faculty Publications

Fifty-five microsatellite markers were scored in an F2 population of pigs (n = 114 females) developed at the University of Nebraska. The population was produced by crossing a line previously selected for 10 generations using an index of ovulation rate and embryonal survival and a line selected at random. The lines were from a common base population and differed by 6.7 ovulations and 3.1 fetuses at 50 d of gestation. Ovulation rate and number of fully formed and mummified pigs were recorded for each female. Data were analyzed with regression models that included random animal effects. Likelihood-ratio tests were …


Outdoor Pig Production In Western Australia. An On-Farm Study To Document Performance And Management Practices On Extensive Pig Farms., Roy Butler Jan 1996

Outdoor Pig Production In Western Australia. An On-Farm Study To Document Performance And Management Practices On Extensive Pig Farms., Roy Butler

All other publications

This paper presents data, collected between 1991 and 1995, relating to the management and performance of 10 extensive piggeries in the south west of Western Australia. The herd sizes varied from 15 to 73 sows and capital investment varied from $144 to $2,000 per sow. Labour costs also varied widely, from $84 to $996 per sow per year. Only 2 of the 10 herds exceeded the PigStats 95 average of 20.1 pigs weaned/sow/year. Pre-weaning mortality was high, and averaged 28.7%. Nine of the herds participated in the state Pig Health Monitoring Scheme and their pigs were inspected at slaughter to …


Growth Of Testes And Testicular Morphology After Eight Generations Of Selection For Increased Predicted Weight Of Testes At 150 Days Of Age In Boars, R. R. Harder, D. D. Lunstra, R. K. Johnson, Roman L. Hruska Oct 1995

Growth Of Testes And Testicular Morphology After Eight Generations Of Selection For Increased Predicted Weight Of Testes At 150 Days Of Age In Boars, R. R. Harder, D. D. Lunstra, R. K. Johnson, Roman L. Hruska

Department of Animal Science: Faculty Publications

Weights of testes and epididymides, body weight, and morphometric measurements of testicular tissue of 75 boars of a line selected for eight generations for predicted weight of testes at 150 d of age and 75 boars of a randomly selected control line were used to evaluate the effects of selection on testicular development at 70, 100, 130, 160, and 450 d of age (n = 15 boars per line per age). Body weights for boars of the select and control line did not differ (P <.05) and the shape of the body growth curve was similar for both lines. Boars of the select line had larger testes than control boars at each age (P < .05), but there was a significant line x age interaction. The percentage increase of the select line mean over the control mean for weight of testes was 37% at 70 d, a maximum of 120% at 100 d, and 25% at 450 d. The percentage of the testes made up of seminiferous tubules differed between lines (P <.01). Lines had similar means of approximately 28% at 70 d and 71% at 450 d, but the mean for the select line was larger between 100 and 160 d of age; the greatest difference was 11.6% (control = 43.7, select = 55.3%) at 100 d. After 70 d of age, select-line boars had a greater percentage of seminiferous tubules with lumens that contained elongated spermatids (P <.l0). The proportion of the testes occupied by Leydig cells was greatest at 70 d, declined sharply between 70 and 130 d with a sharper decline in select-line boars, and then declined more gradually from 130 to 450 d of age. We conclude that selection for weight of testes at 150 d resulted in lower age at puberty for boars of the select line.


Growth Of Testes And Testicular Morphology After Eight Generations Of Selection For Increased Predicted Weight Of Testes At 150 Days Of Age In Boars, R. R. Harder, D. D. Lunstra, R. K. Johnson, Roman L. Hruska Oct 1995

Growth Of Testes And Testicular Morphology After Eight Generations Of Selection For Increased Predicted Weight Of Testes At 150 Days Of Age In Boars, R. R. Harder, D. D. Lunstra, R. K. Johnson, Roman L. Hruska

Department of Animal Science: Faculty Publications

Weights of testes and epididymides, body weight, and morphometric measurements of testicular tissue of 75 boars of a line selected for eight generations for predicted weight of testes at 150 d of age and 75 boars of a randomly selected control line were used to evaluate the effects of selection on testicular development at 70, 100, 130, 160, and 450 d of age (n = 15 boars per line per age). Body weights for boars of the select and control line did not differ (P <.05) and the shape of the body growth curve was similar for both lines. Boars of the select line had larger testes than control boars at each age (P < .05), but there was a significant line x age interaction. The percentage increase of the select line mean over the control mean for weight of testes was 37% at 70 d, a maximum of 120% at 100 d, and 25% at 450 d. The percentage of the testes made up of seminiferous tubules differed between lines (P <.01). Lines had similar means of approximately 28% at 70 d and 71% at 450 d, but the mean for the select line was larger between 100 and 160 d of age; the greatest difference was 11.6% (control = 43.7, select = 55.3%) at 100 d. After 70 d of age, select-line boars had a greater percentage of seminiferous tubules with lumens that contained elongated spermatids (P <.lo). The proportion of the testes occupied by Leydig cells was greatest at 70 d, declined sharply between 70 and 130 d with a sharper decline in select-line boars, and then declined more gradually from 130 to 450 d of age. We conclude that selection for weight of testes at 150 d resulted in lower age at puberty for boars of the select line.


Conflict And Cooperation: Sociobiological Principles And The Behaviour Of Pigs, David Fraser, D. L. Kramer, E. A. Pajor, D. M. Weary Sep 1995

Conflict And Cooperation: Sociobiological Principles And The Behaviour Of Pigs, David Fraser, D. L. Kramer, E. A. Pajor, D. M. Weary

Sociobiology Collection

The pig provides many examples of how principles of behavioural ecology and sociobiology can lead to insights into farm animal behaviour. According to parent-offspring conflict theory, parents should tend to give a level of parental investment somewhat below that solicited by the young. When closely confined during lactation, sows can do little to limit the amount of contact with the piglets, and the young stimulate a prolonged, high level of lactation. Certain alternative housing systems allow the sow to limit the stimulation she receives, and the resulting reduction in lactation can actually be advantageous to both parties. Communal care of …


Ten Generations Of Selection For Predicted Weight Of Testes In Swine: Direct Response And Correlated Response In Body Weight, Backfat, Age At Puberty, And Ovulation Rate, Rodger K. Johnson, Gregg R. Eckardt, Thomas A. Rathje, Denise K. Drudik Oct 1994

Ten Generations Of Selection For Predicted Weight Of Testes In Swine: Direct Response And Correlated Response In Body Weight, Backfat, Age At Puberty, And Ovulation Rate, Rodger K. Johnson, Gregg R. Eckardt, Thomas A. Rathje, Denise K. Drudik

Department of Animal Science: Faculty Publications

Selection for predicted weight of testes at 150 d of age (PWT) was practiced for 10 generations to determine the effect on reproductive and growth traits in swine. Mass selection among boars (line TS) or random selection (line C) was practiced beginning with the F3 generation of a Large White x Landrace composite population. Population size in each line was 40 to 45 litters by 15 sires per generation. Responses were estimated by regressions on cumulative selection differentials for PWT and on generation number and by mixed-model derivative-free REML procedures. The realized heritability of PWT was .35 ± .02 and …