Breeding Herd Research Articles

Factors Affecting Reproductive Efficiency of the Breeding Herd

Factors Affecting Reproductive Efficiency of the Breeding Herd

Growth, body state and breeding performance in gilts and primiparous sows

Optimizing gilt management is a critical point to improve breeding herd efficiency. This review describes the effects of growth rate (GR) and body state at onset of puberty stimulation or at first mating on gilt puberty attainment, productivity and sow longevity. Traditional management practices should be re-evaluated with attention to different modern genotypes. It is difficult to discern the real effects of age, weight, backfat depth and estrus number at first insemination on longevity and reproductive performance, because these variables affect one another. GR interacts with age at boar exposure to influence age at puberty. Higher lifetime GR gilts (>700 g/d) attain puberty earlier and have a lower anoestrus rate. If gilts attain a target weight (135-150 kg), are adapted to herd health status and have at least one previously recorded estrus, they can be inseminated. Overweight at first breeding and throughout gestation should be avoided. There is no advantage in breeding gilts heavier than 150 kg; at first farrowing the target weight is 180-185 kg. Piglet production at first parity may be increased in gilts with a high GR but the number of stillborn piglets can also be increased. The culling rate over 3 parities for locomotion problems, which is one of the major risk factors for reduced herd retention rate, can be increased in overweight gilts at first breeding (>150-170 kg).

Associations among individual gilt birth weight, litter birth weight phenotype, and the efficiency of replacement gilt production.

Selection for larger litter size has increased the number of low individual birth weight (BWi) pigs and produced sows with a repeatable low average litter birth weight phenotype (BWP). Using an average of 3.6 litters records per sow, BWP was established in 644 nucleus-multiplication sows producing replacement gilts in a large commercial operation and classified as low (L-BWP, <1.18 kg, n = 85), medium (M-BWP, ≥1.18 to ≤1.35 kg, n = 250), or high (H-BWP, >1.35 kg, n = 309) on the basis of a BWi of 1.18 kg below which there was a high risk of early mortality and the average BWi (1.35 kg) for the population. In subsequent litters, potential replacement gilts born to these sows (n = 7,341) received a unique identification tag that allowed the impact of BWi, BWP, and their interactions on the efficiency of replacement gilt production to be evaluated. Negative effects of BWi on mortality until day 4 after birth were confirmed (P < 0.05) and cumulative losses to weaning, to day 70 of age, and to final pre-selection at 165 d of age were affected (P ≤ 0.05) by the interaction between BWP and BWi. Among the 2,035 gilts for which records for selection efficiency and production to fourth parity were available, a lower BWi decreased the probability of gilts reaching pubertal estrus (P < 0.05) after 21 and 28 d of boar stimulation starting at 180 d of age, with no effect of BWP. Overall, neither BWi, BWP, nor their interaction affected age at puberty. After breeding, only the main effect of BWP affected productivity and retention in the sow herd. In parities 1 and 2, percent stillborn was higher in litters born to gilts from H-BWP compared with L-BWP dams (P < 0.05), and in parity 2, total born and born alive were lower in sows derived from H-BWP compared with other BWPs. There were no differences in retention based on BWP classes until parity 2, after which retention tended (P ≤ 0.09) to be lower in sows derived from H-BWP compared with L-BWP dams. These results provide evidence that sow BWP is an important factor in the overall efficiency of replacement gilt management. This study also confirms that effective gilt selection and pre-breeding management protocols support excellent sow lifetime productivity and mitigate the risk of a high BWP in the litter of origin affecting retention in the breeding herd.

PRRS eradication from swine farms in five regions of Hungary.

Porcine reproductive and respiratory syndrome (PRRS) causes significant losses to the swine industry worldwide, which leads to launching eradication programmes. The PRRS eradication programme in Hungary is based on the territorial principle, and it is obligatory for each swine farm irrespective of the number of animals kept there. Hungary has an exceptionally large herd size in large-scale pig farms. Large fattening farms operate as all-in/all-out or continuous flow systems. The large-scale breeding herds are predominantly farrow-to-finish types. In large-scale breeding farms, PRRS eradication was carried out by the depopulation-repopulation method in 33 farms, of which 23 received state compensation, 18 farm units either finished production or changed to producing fatteners only. Two farms used the test and removal method for eradication. One farm was classified as 'vaccinated free'. At this farm the breeding animals are vaccinated continuously but there is no vaccination of the progeny at any age, and the PRRS-free status of the farm is strictly controlled and monitored. By 31 December 2019, all pigs in five euroregions of Hungary had become free from PRRS virus, while the PRRS eradication process is still ongoing in the remaining two regions.

Evaluating the efficacy of visual assessment of gilt vulva size prior to puberty on subsequent reproductive performance

This study’s objective was to assess the relationship between visually assigned prepubertal vulva score and subsequent sow productivity in a commercial production system. The study was conducted at a genetic nucleus herd, where farm personnel visually classified prepubertal gilts into categories: vulva score 1 (VS1; below average size), VS2 (average vulva size), and VS3 (above average vulva size), at approximately 15 wk of age. Reproductive performance from gilts incorporated into the breeding herd were tracked through 2 parities of production. Age at parity 1 (P1) was greatest ( P ≤ 0.01) in gilts assigned a VS1 score compared with those receiving a VS2 or VS3 score. The P1 total pigs born for gilts categorized as VS2, VS3, and VS2/3 (VS2 and VS3 combined into one group) was greater ( P ≤ 0.05) compared with gilts receiving a score of VS1. The number of pigs born alive was also lower ( P ≤ 0.05) for gilts assigned a VS1 compared with those assigned VS2 or VS3 and the combined group (VS2/3). Second parity litter performance was not affected ( P > 0.18) by prepubertal vulva score assignment, although total pigs born and pigs born alive through 2 parities combined tended to be greater ( P ≤ 0.08) for gilts in the combined VS2/VS3 group compared with those assigned a score of VS1. These data suggest visually assessing prepubertal vulva development may identify females more likely to farrow at a younger age with improved P1 litter performance.

СВЯЗЬ ЭКСТЕРЬЕРНОЙ ОЦЕНКИ С КРОВНОСТЬЮ ПО РОДСТВЕННЫМ ПОРОДАМ, УЧАСТВУЮЩИМ В ФОРМИРОВАНИИ ГЕНОТИПА ЖИВОТНЫХ

When developing Ayshire breed herds, we used breeding population of related breed: FAY – Finnish Ayshire, SRB – Swedish red, NRF – Norwegian red, CANAY – Canada red, ORDM – Danish red, the research on influence of their blood relation on exterior characteristics of cows is actual. Studied livestock (n=855) has the following blood parts: 56,5±0,55; 12,9±0,31; 10,7±0,16; 17,8±0,60; 0,7±0,08 % consequently. Classes according to blood part, %: 0.0; 0,1 - 12,5; 12,5 - 24,9; 25,0 - 37,4; 37,5 - 49,9; 50,0 - 62,4; 62,5 - 74,9; 75,0 - 87,4; more than 87,5. Blood relationship according to CAN have a positive impact on udder evaluation (+0,130ххх), general view (+0,155ххх), final (+0,164ххх) and identification mark UDC (+0,119ххх), but negative blood relationship according to FAY on general view (-0,138ххх), according to SRB and NRF breed – on udder evaluation (-0,163ххх; -0,111ххх) and final (-0,133ххх; -0,100хх). Difference between force coefficient influence of blood relationship on exterior features according to FAY and CAN ranges from 7,9 to 18,7 units, and on UDC and FLC s equal to 6,6 and 3,5 units. Joint effect of blood relationship according to FAY and CAN is lower on lineal feature, and on exterior indices it increases. For improvement of individual exterior features account must be taken of blood relationship element at proband according to particular related breed of Ayshire group of diary cattle, focusing on blood element on FAY and CAN and their combinations.

Influence of transcervical infusion of seminal plasma on the farrowing rate and litter size in artificially inseminated sows

ABSTRACT Recent studies have focused on the use of seminal plasma to increase sow fertility after classical intracervical artificial insemination (AI). The aim of the present study was to investigate the influence of seminal plasma infusion, prior to the application of conventional AI dose, on the fertility rate in sows. A total of 114 sows were treated with intrauterine infusion of 30ml seminal plasma (SP), while 114 control sows were infused by physiological solution (PS), immediately before the application of conventional AI dose. The experiment was conducted at one commercial pig farm in Serbia, which is comprised of 1,500 sows in the breeding herd. Intrauterine infusion of seminal plasma produced significantly (P&lt;0.05) higher farrowing rate (93.8%) and significantly (P&lt;0.01) more live-born piglets per litter (12.27), compared with the control sows (83.33% farrowing rate and 10.48 piglets). The present results show that intrauterine infusion of seminal plasma can be a useful tool for increasing the fertility rate in artificially inseminated sows, under the conditions of practical intensive pig production.

Spatial relative risk and factors associated with porcine reproductive and respiratory syndrome outbreaks in United States breeding herds

Details of incident cases of porcine reproductive and respiratory syndrome (PRRS) in United States breeding herds were obtained from the Morrison’s Swine Health Monitoring Project. Herds were classified as cases if they reported an outbreak in a given season of the year and non-cases if they reported it in a season other than the case season or if they did not report a PRRS outbreak in any season. The geographic distribution of cases and non-cases was compared in each season of the year. The density of farms that had a PRRS outbreak during summer was higher in Southern Minnesota and Northwest-central Iowa compared to the density of the underlying population of non-case farms. This does not mean that PRRS outbreaks are more frequent during summer in absolute terms, but that there was a geographical clustering of herds breaking during summer in this area. Similar findings were observed in autumn. In addition, the density of farms reporting spring outbreaks was higher in the Southeast of the United States compared to that of the underlying population of non-case farms. A similar geographical clustering of PRRS outbreaks was observed during winter in the Southeast of the United States. Multivariable analyses, adjusting for the effect of known confounders, showed that the incidence rate of PRRS was significantly lower during winter and autumn during the porcine epidemic diarrhea (PED) epidemic years (2013−2014), compared to PRRS incidence rates observed during the winter and autumn of PED pre-epidemic years (2009−2012). After 2014, an increase in the incidence rate of PRRS was observed during winter and spring but not during autumn or summer. Pig dense areas were associated with a higher incidence rate throughout the year. However, this association tended to be stronger during the summer. Additionally, herds with ≥2500 sows had an increased incidence rate during all seasons except spring compared to those with <2500 sows. PRRS incidence was lower in year-round air-filtered herds compared to non-filtered herds throughout the year. We showed that not only the spatial risk of PRRS varies regionally according to the season of the year, but also that the effect of swine density, herd size and air filtering on PRRS incidence may also vary according to the season of the year. Further studies should investigate regional and seasonal drivers of disease. Breeding herds should maintain high biosecurity standards throughout the year.

Bio-economic evaluation of grazing-management options for beef cattle enterprises during drought episodes in semiarid grasslands of northern Australia

Context The large inter-annual and decadal rainfall variability that occurs in northern Australian rangelands poses major challenges for the profitable and sustainable management of grazing businesses. Aims An integrated bio-economic modelling framework (GRASP integrated with Breedcow and Dynama (BCD)) was developed to assess the effect of alternative grazing-management options on the profitability and sustainability of a beef cattle enterprise in the central-western Mitchell grasslands of Queensland over a multi-decadal time period. Methods Four grazing-management strategies were simulated over a 36-year period (1982–2017) in the GRASP pasture-growth model, using historic climate records for Longreach in central-western Queensland. Simulated annual stocking rates and steer liveweight-gain predictions from GRASP were integrated with published functions for mortality and conception rates in beef-breeding cattle in northern Australia, and then used to develop dynamic BCD cattle-herd models and discounted cash-flow budgets over the last 30 years of the period (1988–2017), following a 6-year model-equilibration period. The grazing-management strategies differed in the extent to which stocking rates were adjusted each year, from a common starting point in Year 1, in response to changes in the amount of forage available at the end of the summer growing season (May). They ranged from a low flexibility of ‘Safe stocking rate’ (SSR) and ‘Retain core herd’ (RCH) strategies, to a moderate flexibility of ‘Drought responsive’ (DR), to a ‘Fully flexible’ (FF) strategy. The RCH strategy included the following two herd-management scenarios: (1) ‘Retain herd structure’, where a mix of cattle were sold in response to low pasture availability, and (2) ‘Retain core breeders’, where steers were sold before reducing the breeder herd. Herd-management scenarios within the DR and FF strategies examined five and four options respectively, to rebuild cattle numbers and utilise available pasture following herd reductions made in response to drought. Key results Property-level investment returns expressed as the internal rate of return (IRR) were poor for SSR (–0.09%) and the three other strategies when the herd was rebuilt following drought through natural increase alone (RCH, –0.27%; DR, –1.57%; and FF, –4.44%). However, positive IRR were achieved when the DR herd was rebuilt through purchasing a mix of cattle (1.70%), purchasing pregnant cows (1.45%), trading steers (0.50%) or accepting cattle on agistment (0.19%). A positive IRR of 0.70% was also achieved for the FF property when purchasing a mix of cattle to rebuild numbers. However, negative returns were obtained when either trading steers (–2.60%) or agistment (–0.11%) scenarios were applied to the FF property. Strategies that were either inflexible or highly flexible increased the risk of financial losses and business failure. Property-level pasture condition (expressed as the percentage of perennial grasses; %P) was initially 69%P and was maintained under the DR strategy (68%P; average of final 5 years). The SSR strategy increased pasture condition by 25% to 86%P, while the RCH and FF strategies decreased pasture condition by 29% (49%P) and 65% (24%P) respectively. Conclusions In a highly variable and unpredictable climate, managing stocking rates with a moderate degree of flexibility in response to pasture availability (DR) was the most profitable approach and also maintained pasture condition. However, it was essential to economic viability that the property was re-stocked as soon as possible, in line with pasture availability, once good seasonal conditions returned. Implications This bio-economic modelling analysis refines current grazing-management recommendations by providing insights into both the economic and sustainability consequences of stocking-rate flexibility in response to fluctuating pasture supply. Caution should be exercised in recommending either overly conservative safe stocking strategies that are inflexible, or overly flexible stocking strategies, due to the increased risk of very poor outcomes.

Breeding soundness examination and herd proficiency of local genetic groups of bulls in tropical environment conditions in Veracruz, Mexico

With the aim of assessing bull fertility before or during its use for reproduction under tropical weather conditions where heat stress is present, and correlating it to herd parameters, BSE was carried out to determine which genetic groups of bulls have better reproductive performance. 223 bulls from different genetic groups, Zebu bulls (N = 72), European bulls (N = 58), and Crossbred Bulls (N = 93), were evaluated in situ over a two-year period, 2018–2019. Bull (age, corporal conditions, libido, and scrotal circumference), semen (concentration, motility and volume), herd (pregnancy rate and calving intervals) and environmental variables (THI, season, sampling month and spermatogenesis month) were analysed with One-Way ANOVA, as well as with factorial, multiple regression, and multivariate analysis. Zebu and European bulls have a higher libido than crossbreed bulls (p < .05), and it decreases with age (p < .05). High-libido bulls (>7) show high correlation (R = 0.70 p < .05) with herd parameters; BCS affects libido (p < .05). Sperm concentration is correlated to herd parameters (R = 0.82 p < .05). European bull sperm concentration and motility showed a decrease in autumn and winter (p < .05) in comparison to other genetic groups. Libido and semen variables are more associated with herd parameters than with other bull characteristics. Environmental variables are not associated with herd parameters (p > .05). Heat stress did not directly affect bull reproductive performance; Zebu bulls and crossbreeds showed better herd parameters (p < .05). Highlights Bull breeding soundness examination and herd proficiency. Herd proficiency of local genetic groups of bulls in tropical conditions. Breeding soundness examination in tropical environment conditions.

Evaluation of viral RNA extraction methods to detect porcine reproductive and respiratory syndrome and influenza A viruses from used commercial HVAC air filters from swine farms

Filtering the air entering swine farms has significantly reduced the incidence of porcine reproductive and respiratory syndrome virus (PRRSv) infections in Midwestern breeding herds. Despite the significant investment made in installation of air filters, the nature and type of viruses trapped by these filters are not yet clear because of the unavailability of reliable methods to elute and detect these viruses. Here we report that eluting viral particles from the air filters by grinding filter specimens with liquid nitrogen, coupled with TRIzol reagent to extract RNA can detect both PRRSv and influenza A virus (IAV) from used minimum efficiency reporting value (MERV) 14, 15 and 16 rated air filters. PRRSv was detected in 27% (12/44) and IAV was detected in 66% (29/44) of filters that had been in installation between 08/12/13 and 07/12/17. Interestingly, PRRSv was also detected on used filters from farms with PRRSv negative status at the time of filter removal. Presence of PRRSv and IAV in the used filters show likely evidence of between herd aerosol spread for these viruses. The methods derived from this study open up avenues to further investigate airborne transmission and risk of virus introduction into farms contributing to the control of diseases in swine.

The influence of water-soluble antioxidant on the productivity of chickens and hatching quality of eggs

The aim of the study was to obtain physiological, biochemical and zootechnical data confirming the effective use of the antioxidant dihydroethoxychine to increase productivity in laying hens. The experiment was carried out on 2 groups of laying hens of the breeding herd, selected by 100 heads by random sampling. For 41 days, the chickens of the experimental group received a basic diet with the addition of dihydroethoxychine (DGE) in the amount of 100 mg/kg of feed. On the 25th day of the experiment, blood samples (n=5) were taken for biochemical studies. In the experimental group, the concentration of cholesterol in the fraction of high-density lipoproteins increased twofold (P<0.01) and in the fraction of low-density lipoproteins decreased by almost 50% (P<0.01) against the control. The concentration of MDA in the blood of chickens in the experimental group was 82.00% relative to that in the control, and in the yolk of the egg - only 37.42 %. Egg production of chickens in the experimental group was higher than in the control by 7.3% (P<0.1). Hatchability of chickens in the experimental group increased by 14.6% (P<0.01) relative to control. It was concluded that the tested water-soluble antioxidant has a positive effect on the biological functions and productive parameters of laying hens.

Shotgun proteome analysis of seminal plasma differentiate boars by reproductive performance

There is a need to identify subfertile boars before they enter into the breeding herd. Seminal plasma proteins are essential for normal sperm function and transport and play an important role in fertilization. The objective of this study was to use liquid chromatography tandem mass spectrometry for shotgun proteome analysis to investigate whether differences in boar fertility phenotype can be differentiated by seminal plasma protein abundance. Following 50 breedings, boars were categorized into one of four phenotypes: high farrowing rate and total born (HFHB; n = 9), high farrowing rate with low total born (HFLB; n = 10), low farrowing rate and total born (LFLB; n = 9), and low farrowing rate with high total born (LFHB; n = 4) that were distinct (p < 0.05) from each other by these variables. There were 506 proteins measured in at least one sample across all animals. There were 245 high confidence proteins and 56 were differentially abundant between the high fertility phenotype (HFHB) and at least one of the three subfertile groups. Findings support that seminal plasma protein profiles are distinct between boars with different fertility phenotypes.

Influenza A virus vaccine research conducted in swine from 1990 to May 2018: A scoping review.

BackgroundInfluenza A viruses of swine (IAV-S) are a global zoonotic and economic concern. Primary control is through vaccination yet a formal evidence map summarizing vaccine research conducted in pigs is not available.ObjectiveTen characteristics of English language primary IAV-S vaccine research, conducted at the level of the pig or higher, were charted to identify research gaps, topics for systematic review, and coverage across different publication types.DesignSix online databases and grey literature were searched, without geographic, population, or study type restrictions, and abstracts screened independently and in duplicate for relevant research published between 1990 and May 2018. Full text data was charted by a single reviewer.ResultsOver 11,000 unique citations were screened, identifying 376 for charting, including 175 proceedings from 60 conferences, and 170 journal articles from 51 journals. Reported outcomes were heterogeneous with measures of immunity (86%, n = 323) and virus detection (65%, n = 246) reported far more than production metrics (9%, n = 32). Study of transmissibility under conditions of natural exposure (n = 7), use of mathematical modelling (n = 11), and autogenous vaccine research reported in journals (n = 7), was limited.ConclusionsMost research used challenge trials (n = 219) and may have poor field relevance or suitability for systematic review if the purpose is to inform clinical decisions. Literature on vaccinated breeding herds (n = 89) and weaned pigs (n = 136) is potentially sufficient for systematic review. Research under field conditions is limited, disproportionately reported in conference proceedings versus journal articles, and may be insufficient to support systematic review.

Effect of influenza A virus sow vaccination on infection in pigs at weaning: A prospective longitudinal study.

Although vaccination is the main measure to control influenza A virus (IAV) in swine, there is limited information on the efficacy of sow vaccination on reducing IAV infections in pigs at weaning. We assessed the effect of sow vaccination on IAV infection in pigs at weaning in a cohort of 52 breeding herds studied prospectively. Herds were voluntarily enrolled according to their IAV history, sow vaccination protocol and monitored during six months (prospective longitudinal study). On each herd, nasal swabs were collected monthly from 30 pigs at weaning and tested for IAV by RT-PCR. IAV was detected in 25% (75/305) of sampling events. Of 9,150 nasal swab pools (3 individual nasal swabs/pool), 15% (458/3050) of pools tested IAV positive. IAV infections in pigs at weaning were lower in vaccinated herds compared to non-vaccinated ones. Moreover, no significant differences were seen between prefarrow and whole herd protocols, or the use of commercial versus autogenous IAV vaccines. Prefarrow and whole herd vaccination protocols reduced the odds of groups testing IAV positive at weaning in comparison with no vaccination. Our results are relevant when considering implementation of sow vaccination to control influenza infections in pigs at weaning and, hence, minimize transmission to growing pigs and other farms.

Genome-Wide Association Study of Body Weights in Hu Sheep and Population Verification of Related Single-Nucleotide Polymorphisms.

Body weight (BW) is a critical economic trait for meat production in sheep. The current study aimed to perform a genome-wide association study (GWAS) to detect significant single-nucleotide polymorphisms (SNPs) that are associated with BW in Hu sheep. The comparison and analysis of the G1 and G2 generations of a nucleus meat Hu sheep breeding herd revealed four SNPs identified by GWAS. The subsequent verification of the significant SNP loci in the Hu sheep G3 generation nucleus herd also detected nine SNPs in significant SNP regions. Two SNPs were significantly associated with the BW of Hu sheep (p < 0.05). OARX_76354330.1 and s64890.1 could be identified as functional SNPs for the growth traits of Hu sheep. CAPN6, as a candidate gene, was significantly different in the biceps femoris and longissimus dorsi muscles of weaning (60-day) and 6-month sheep, which facilitated the discovery of causal variants for BW and contributed to the marker-assisted selection breeding of Hu sheep.

The evaluation of productive traits of pigs with application methods of population selection and molecular genetic markers

The comprehensive evaluation of the productive traits of the initial genotypes of pigs in the creation of breeding herds using population selection methods has been carried out. Based on the results of evaluating the growth and development of breeding animals using the methods of index selection and DNA testing for the genes markers RYR1, ESR, IGF-2, MUC4 the genealogical structure of breeding herds has been formed on the basis of new stud lines of Belarusian stud type of pigs of Yorkshire breed. It has been found that sows of new lines had high reproduction rates: prolifi cacy was 11,6 piglets, milk capacity was 59,1 kg, number of piglets at weaning was 11,2 heads, and litter weight at weaning was 103,6 kg. The breeding herd of two new stud lines is represented by boars of the line Drug 6805 and Dobry 2313. The average productivity of boars-line continuers was: the age of reaching a live weight of 100 kg to 160 days, the average daily gain from birth to reaching the live weight of 100 kg was 636 g. At the age of 12 months, the live weight and body length of replacement boars were 268 kg and 175 cm, the thickness of the fat was 8,9 mm, the height of the longest back muscle was 51,5 mm, the content of lean meat in the body was 62,6 %, which corresponds to the class “elite”. Boars have been separated into reproductive traits. Improvement of lines is carried out through the continuators of related groups. Analysis of genetic studies of animals of new stud lines has shown that they have a high frequency of occurrence of desirable alleles by genes: RYR1 (stress-resistant animals) – 1,0; IGF-2 (fattening and meat traits) – 0,783; ESR (reproductive traits) – 0,608; MUC4 – (resistance to escherichiosis) – 0,786.

Predicting methane emissions, animal-environmental metrics and carbon footprint from Brahman (Bos indicus) breeding herd systems based on long-term research on grazing of neotropical savanna and Brachiaria decumbens pastures

Beef cattle production constitutes the main land use in the neotropical savannas of the eastern Colombian Orinoquia. However, the effects of Brachiaria decumbens Stapf (Bd) pastures and the alternative combination of savanna and B. decumbens pastures (SaBd) to raise and breed tropical beef heifers and cows, and their impacts on methane (CH4) emissions and overall carbon (C) footprint are still unknown. This study aimed to predict CH4 emissions, animal-environmental metrics and overall C footprint across heifers' growth, cow-calf-bull and cull cows' fattening productive stages of Brahman (Bos indicus) breeding herds, lifetime-grazing on B. decumbens pastures or a sequence of native savanna and B. decumbens pastures. A dynamic model-method was used with detailed liveweight (LW) and productive lifetime-cows' data together with estimated values of above- and belowground pasture biomass and soil C stocks. This framework recognized commercial farming practices such as growing and mating female herds on Bd (Bd scenario) or rising them on savanna and grazing Bd pastures (SaBd scenario) during the herd's breeding life. The study complemented this socio-economic, cultural and productive tradition by fattening cull cows using the improved Bd pasture and illustrated the cointegrating relationship with structural-flows of LW-derived CH4 emissions. As heifers aged, accumulated CH4 emission efficiencies [t carbon dioxide (CO2) equivalent (CO2-eq) head −1] were lower in the Bd scenario than in the SaBd scenario from birth to conception (2.67 ± 0.087 vs 3.49 ± 0.087; P < .0001), while following the same trend, emissions from the first to the fourth lactation were in the range of 0.821–0.865 (P < .05) between scenarios, but similar in the two other lactations. Methane efficiency estimates from cow-calf pairs (t CO2-eq kg −1 calf born) tended to be lower in the Bd scenario than in the SaBd scenario up to the fourth lactation. In the extreme, calculated values during the fattening phase were 0.935 t CO2-eq head −1. In this context, the estimated animal greenhouse gas emissions and annual soil C accumulation values revealed not only a differentiation of the estimated C footprint at system level between animal productive stages, but also more likely natural CO2 removal from the atmosphere with all three animal phases of Bd scenarios. Hence, this study provides evidence for the experimental hypothesis that dynamic modelling based on long-term research results on improved Bd pastures would allow the estimation of the overall C footprint of Brahman breeding herds and their sustainable performance in the Colombian neotropical savanna environment.

Monitoring the time-grade required for extrusion of oocytes reproductive from colossoma macropomum

The water temperature of the tanks of the breeding herds exerts a strong influence on the process of artificial reproduction. Its monitoring through the hour-degree, serves to assist in the moment to be made the extrusion of the oocytes. The objective was to monitor the time-degree that Colossoma macropomum females need after the second dose of the hormonal induction protocol, until the time of extrusion of their oocytes. The analysis was carried out at the Fish Fishery in the municipality of Sorriso-MT. Nine breeding women were submitted to the protocol of hormonal induction with pituitary extract of carp being administered in two doses. In the former, the dose of 0.5 mg / kg was used and the second dose was 5 mg / kg body weight, with an interval of 12 hours. From the second dose, the temperature in degrees centigrade of the water from the tanks was monitored hourly until the time of oocyte extrusion. Breeders had muscle tremors, swimming in circles, and were more agitated nine hours after the second dose. The oocytes had a yellowish-brown appearance, and some had individual features. The sum of the temperature of the water in hours-degree obtained was of 243. The temperature of the water did not present variation, maintaining itself at 27 ° C. It is concluded that an hour-degree is necessary for an extrusion of oocytes in some of the things you can find in Colossoma Macropomum of 243, agreeing with the limits proposed in the literature.

Heat-No-Service: Reproductive lifetime performance of gilts inseminated on first versus second observed estrus in commercial piglet producing herds

Heat No Service (HNS) is an increasing managerial decision made in commercial piglet producing herds. Performance of gilts has been shown to be influenced by initial decisions made on them at their introduction in the breeding herds. Lifetime Reproductive performance comprising of parity total born piglets and lifetime total born piglets of gilts initially bred on first observed estrus (0HNS) was compared with that of gilts bred on second observed estrus (1HNS). Stored data from Porcitec database consisted of 2.072 gilts bred on first observed estrus (0HNS) and 2.453 gilts bred on second observed estrus (1HNS) totaling to 4.525 gilts. Data was statistically analyzed using the GLM procedure of IBM SPSS version 25. The results showed a significance difference (p&lt;0.001) in lifetime total born performance of gilts bred at 0HNS (mean 93.9) and 1HNS (mean 95.7). There was also a significant difference (p&lt;0.001) of total born piglets in parity 1, 5 and 6 in the 2 groups. There was an observed increased parity total born and lifetime total born when first time insemination of gilts was delayed to second estrus. The findings in this study favor the 1HNS breeding with an overall increased lifetime total born. Gilts inseminated at 1HNS produce 1.57 more pigs for lifetime as compared with those inseminated at 0HNS when observation is made up to P6. Producers in piglet producing herds could re examine their decisions for increased productivity by promoting many gilts into 1HNS but still maintaining the balance between breed targets and production schedules to remain competitive and profitable in the current global swine industry.