Reproductive Potential of Red Chittagong Cattle in Bangladesh

The study was carried out to investigate the phenotypic and genetic potential of reproductive traits of Red Chittagong Cattle (RCC) of Bangladesh. For that purpose accumulated data on a total of 101 animals from four different herds covering a period from 2005 to 2011 were used for analyses. The overall mean (±SE) values of age at first heat (AFH), age at first conception (AFC), age at first calving (AC), calving rate per productive year (CR), interval to post partum heat (IPPH), days open (DO), calving interval (CI) and generation interval (GI) were 35.9±1.1 month, 42.1±1.3 month, 50.6±1.1 month, 0.87±0.01 month, 149.4±9.5 days, 178.6±11.0 days, 454.9±10.4 days and 4.2±0.1 year, respectively. The factors having significant effects on reproductive traits were herd on DO and CI and calving year on DO. Calving parity and calving season had no significant effect on those traits. The heritability estimates of IPPH, DO and CI were very low (0, 0.06 and 0.09) and that of corresponding repeatability estimates were also low (0.06, 0.08 and 0.09, respectively). The heritability estimates for other traits were moderate (0.39 to 0.50). The results indicated that though reproductive potential of RCC for most of the traits are below than expected, that may be due to their lower inherent capability of indigenous Zebu compared to Taurus, but there is still opportunity of considerable improvement of these traits studied as indicated by their phenotypic variations among population.

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80 Evaluation of extended release eprinomectin efficacy on multiparous beef cow performance

Journal of Animal Science ◽

10.1093/jas/skz397.024 ◽

2020 ◽

Vol 98 (Supplement_2) ◽

pp. 11-11

Author(s):

Laine Zammit ◽

Jermey G Powell ◽

Reagan N Cauble ◽

Toby D Lester ◽

Callan Lichtenwalter ◽

...

Keyword(s):

Extended Release ◽

Reproductive Traits ◽

Economic Loss ◽

Beef Cows ◽

Negative Control ◽

Beef Cow ◽

Body Weights ◽

Calving Season ◽

Cow Performance ◽

Fall Calving

Abstract Internal parasitism inevitability prompts economic loss in beef cattle production by decreasing growth performance and reproductive traits. Previous studies have conflicting results on the macrocyclic lactones (ML) efficacy against internal parasitism. The objective of this study was to evaluate the efficacy of milbeymycin and avermectin sub groups of ML on cow performance. Multiparous fall calving, crossbred beef cows (n = 106) were allocated randomly to 1 of 3 anthelmintic treatments: 1) Negative control (CON), in which cows did not receive an anthelmintic, 2) Injectable moxidectin (MOX) and 3) Injectable extended release eprinomectin (ERE). Body weights (BW), body condition scores (BCS), and fecal egg counts (FEC) were taken throughout the duration of the calving season to weaning on d0, d80, d162, and d217, with weaning occurring on d217. Performance data were analyzed using the MIXED procedures of SAS, and pregnancy data were analyzed using the GENMOD procedures of SAS. Significance was fixed at P < 0.05 and tendencies were established from 0.05 ≤ P ≤ 0.10. There was no effect of anthelmintic treatment on cow BW (P ≥ 0.57) or cow BCS (P ≥ 0.22) during the 217 d study; however, CON cows tended to have lower BCS (P = 0.08) throughout the duration of the study. Cows treated with ERE had fewer FEC compared to MOX and CON groups (P ≤ 0.001) and tended to improve pregnancy rates (c2 = 0.0546). Calf weaning weight was similar among treatments averaging 216, 225, and 223 kg regarding CON, MOX, and ERE cow treatments, respectively.

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The effects of days-open on milk yield and on breeding policy post partum

Animal Science ◽

10.1017/s0003356100012204 ◽

1979 ◽

Vol 29 (1) ◽

pp. 109-119 ◽

Cited By ~ 44

Author(s):

R. Bar-Anan ◽

M. Soller

Keyword(s):

Milk Production ◽

Milk Yield ◽

Post Partum ◽

Economic Value ◽

Total Yield ◽

Annual Production ◽

Initial Yield ◽

Days Open

ABSTRACTThe effects of days-open on milk yields in current lactations and in following lactations were estimated from 71 911 current and 68 693 following lactation records. Yields were expressed as 305-day, total and annual records, where annual record = 365 × (total yield/days between calvings).The data were grouped according to current days-open, corrected for initial yield differences and analysed separately for heifers and cows in Moshav (moderate-yielding) and Kibbutz (high-yielding) herds. Current 305-day records increased by 15 to 18 kg milk/day-open up to 90 days-open, and 2 to 3 kg/day-open thereafter. In contrast, the effects of increasing days-open on annual yields were generally small and negative, being positive only for heifers up to 90 days-open. Thus 305-day records heavily under-rated annual yields of fertile cows. For current lactations, 70 to 100 days-open for heifers and 30 to 50 days-open for cows resulted in the highest annual production. Yields in following lactations were positively associated with days-open in the previous lactation. The effect was highest in high-yielding herds, suggesting that high-yielding cows respond positively to some rest between calvings.Combining the effects of days-open on current and following lactation yields and on the calf crop: in high-yielding herds heifers had the highest productivity when mated not earlier than 70 days post partum, while in moderately-yielding herds days-open did not affect productivity. Cows in high-yielding herds achieved highest productivity at 41 to 90 days-open, while cows in moderately-yielding herds were most productive when mated as early as possible.A comparison of the economic value of sire fertility and sire transmitting ability for milk production showed that fertility may often be over-rated.

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Ovigeny strategy of the parasitic wasp Cosmocomoidea annulicornis (Hymenoptera: Mymaridae): effect of female age, feeding and host availability on reproductive traits

Bulletin of Entomological Research ◽

10.1017/s0007485321000766 ◽

2021 ◽

pp. 1-8

Author(s):

Carolina Manzano ◽

Eduardo G. Virla ◽

Maria V. Coll Araoz ◽

Erica Luft-Albarracin

Keyword(s):

Body Size ◽

Parasitic Wasp ◽

Reproductive Potential ◽

Reproductive Traits ◽

Egg Load ◽

Biological Traits ◽

Potential Fecundity ◽

Female Age ◽

Host Availability ◽

Egg Maturation

Abstract The reproductive traits of the mymarid wasp Cosmocomoidea annulicornis (Ogloblin) (Hymenoptera: Mymaridae) attacking eggs of the sharpshooter Tapajosa rubromarginata (Signoret) (Hemiptera: Cicadellidae) were evaluated under laboratory conditions. Bioassays were carried out to estimate the realized fecundity and egg load of females. The ovigeny index was calculated and different biological traits, such as body size, oöcyte length, gaster length and wing length, were analysed to assess significant associations between these traits and the species fitness. In addition, the effect of host availability and feeding on longevity and potential fecundity throughout life and the effect of female age on egg maturation dynamics were assessed. The results showed that C. annulicornis is a strongly synovigenic species. A positive correlation was found between fecundity and longevity of the females and between body size and oöcyte length. Contrary to expected, body size was not related to fecundity and longevity. Females lived significantly longer in the presence of hosts and honey than when they were host-deprived and honey-fed or both host and honey deprived. Host availability had a significant effect on the amount of eggs laid by C. annulicornis females. Female age was negatively associated with oöcyte length. Furthermore, females were able to mature additional eggs as they aged, nevertheless, when host-deprived, senescent females presented significantly less mature eggs than younger ones, suggesting a possible egg oosorption. These results might contribute to a better understanding of the reproductive potential of this species as a biocontrol agent.

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The impact of intrapopulation variability in reproductive traits on population reproductive potential of Grand Bank American plaice (Hippoglossoides platessoides) and yellowtail flounder (Limanda ferruginea)

Journal of Sea Research ◽

10.1016/j.seares.2007.12.001 ◽

2008 ◽

Vol 59 (3) ◽

pp. 186-197 ◽

Cited By ~ 17

Author(s):

M.J. Morgan ◽

R.M. Rideout

Keyword(s):

Reproductive Potential ◽

Reproductive Traits ◽

Yellowtail Flounder ◽

Limanda Ferruginea ◽

Intrapopulation Variability ◽

The Impact ◽

Hippoglossoides Platessoides

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Genetic parameter estimates (full sib and half sib analysis) of fertility and hatchability in two strains of Rhode Island chickens

Nigerian Journal of Animal Production ◽

10.51791/njap.v38i1.706 ◽

2021 ◽

Vol 38 (1) ◽

pp. 14-22

Author(s):

M. Orunmuyi ◽

I. A. Adeyinka ◽

O.O Oni

Keyword(s):

Rhode Island ◽

Additive Genetic Variance ◽

Genetic Parameter ◽

Genetic Correlations ◽

Reproductive Traits ◽

Parameter Estimates ◽

Phenotypic Correlations ◽

Poultry Breeding ◽

Genetic And Phenotypic Correlations ◽

Heritability Estimates

A study was conducted to estimate the genetic parameters of fertility and hatchability in two strains of Rhode Island Red (RIR) Chickens denoted as Strain A and Strain B respectively using the full-sib (sire +dam variance) and maternal half-sib (dam variance) components. The birds were obtained from the selected populations of RIR Chickens kept at the poultry breeding programme of National Animal Production Research Institute, Shika, Zaria, Nigeria. Settable eggs were collected from mating 28 cocks to 252 hens in a ratio of 1cock:9 hens from each strain. Eggs were pedigreed according to sire and dam. Results showed that values obtained for number of egg set (EGGSET), number of fertile eggs (NFERT), number of hatched chicks (NHATCH), percentage of chicks hatched from total eggs set (PHATCH) and percentage of chicks hatched from fertile eggs (PHATCHBL) were all higher in strain A than strain B. Heritability estimates obtained from the full-sib and maternal half-sib analysis ranged from medium to high for the two strains (0.24-0.96). The maternal half sib estimates were higher (0.40-0.96) than the estimates obtained from full sibs (0.24- 0.48). Genetic and phenotypic correlations obtained for both strains were positive and similar regardless of method of estimation. Genetic correlations between EGGSET and PFERT were low in strain A using both full-sib and maternal half-sib analyses (0.09-0.14). Phenotypic correlations between EGGSET and PFERT, PHATCH and PHATCHBL were also low in both strains and regardless of method of analyses. Moderate to high heritability estimates suggest that genetic improvement can be obtained by selection of these reproductive traits. The full-sib analysis for estimating heritability will be preferred since it is assumed that only additive genetic variance contributes to the covariance between family members.

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Definition of subgroups for fixed regression in the test-day animal model for milk production ofHolsteincattle in theCzech Republic

Czech Journal of Animal Science ◽

10.17221/3976-cjas ◽

2011 ◽

Vol 50 (No. 1) ◽

pp. 7-13 ◽

Cited By ~ 3

Author(s):

L. Zavadilová ◽

E. Němcová ◽

J. Přibyl ◽

J. Wolf

Keyword(s):

Animal Model ◽

Milk Production ◽

Legendre Polynomials ◽

Environmental Effect ◽

Random Regression ◽

Breeding Values ◽

Regression Test ◽

Days Open ◽

Calving Season ◽

Definition Of

The investigation was based on roughly 3.9, 2.7 and 1.7 million test-day records from first, second and third lactation, respectively, sampled from 596 200 Czech Holstein cows between the years 1991 and 2002. Breeding values were estimated from multi-lactation random-regression test-day models which contained the fixed effect of herd-test day, fixed regression on days in milk and random regressions on the animal level and the permanent environmental effect. Third degree Legendre polynomials (with four coefficients) were used for both the fixed and random regressions. The models differed in fixed regression. In Analysis I, 96 subclasses were defined according to age at calving, season and year of calving within lactation. In Analysis II, days open were additionally included as a grouping factor resulting in 480 subclasses. Rank correlations over 0.98 between both analyses were observed for breeding values for sires. Grouping according to Analysis I was recommended.  

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Tall Fescue Toxicosis Mitigation Strategies: Comparisons of Cow-Calf Returns in Spring- and Fall-Calving Herds

Journal of Agricultural and Applied Economics ◽

10.1017/s1074070800024123 ◽

2012 ◽

Vol 44 (4) ◽

pp. 577-592 ◽

Cited By ~ 9

Author(s):

Stephen A. Smith ◽

James D. Caldwell ◽

Michael P. Popp ◽

Kenneth P. Coffey ◽

John A. Jennings ◽

...

Keyword(s):

Tall Fescue ◽

Mitigation Strategies ◽

Fescue Toxicosis ◽

South Central ◽

Central United States ◽

Calving Rate ◽

Cow Calf ◽

Calving Season ◽

Fall Calving ◽

Tall Fescue Toxicosis

Tall fescue toxicosis adversely affects calving rate and weight gains reducing returns to cow-calf producers in the south–central United States. This grazing study estimated animal and economic performance implications of endophyte-infected fescue and calving season. Establishing novel endophyte-infected tall fescue on 25% of pasture acres resulted in improved calving rates (87% vs. 70%), weaning weights (532 lbs vs. 513 lbs), and partial returns per acre ($257 vs. $217). Additionally, fall-calving cows had higher calving rates (91% vs. 67%), weaning weights (550 lbs vs. 496 lbs), and partial returns per acre ($269 vs. $199) than spring calving cows.

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Body composition and performance of autumn-calving Holstein-Friesian dairy cows during lactation: metabolic activityin vitroof subcutaneous adipose tissue

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s0308229600022157 ◽

1992 ◽

Vol 1992 ◽

pp. 104-104

Author(s):

A. Walsh ◽

J. D. Sutton ◽

D. E. Beever

Keyword(s):

Adipose Tissue ◽

Dairy Cows ◽

Body Fat ◽

Post Partum ◽

Additional Source ◽

Genetic Potential ◽

Holstein Friesian ◽

And Performance ◽

Lactation Cycle ◽

Subcutaneous Adipose

In early lactation dairy cows use stored body fat to provide an additional source of energy to support milk production and these reserves are replaced when energy requirements for milk synthesis are reduced. The extent to which body fat is mobilized depends on the nutritional state of the animal and its genetic potential. These changes are accompanied by substantial alterations in the intermediary metabolism of adipose tissue. The aim of this work was to investigate the timing and magnitude of changes in synthetic and lipolytic pathways in adipose tissue from dairy cows during a lactation cycle and at three levels of energy intake.Fifty four cows were fed grass silagead libitumand a concentrate ration at 3(L), 6(M) or 9(H) kg DM/day (Sutton et al 1992). An initial group of six cows was slaughtered at 2 to 4 dayspost partum(week 0) followed by two cows from each treatment at weeks 2, 5, 8, 11, 14, 19, 24 and 29.

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Phenotypic and genetic parameters for reproductive performance in a synthetic line of sheep

The Journal of Agricultural Science ◽

10.1017/s0021859600031920 ◽

1981 ◽

Vol 96 (1) ◽

pp. 107-113 ◽

Cited By ~ 11

Author(s):

T. G. Martin ◽

D. Nicholson ◽

C. Smith ◽

D. I. Sales

Keyword(s):

Reproductive Performance ◽

Genetic Parameters ◽

Genetic Correlations ◽

Reproductive Traits ◽

Direct Selection ◽

Sex Distribution ◽

Regression Methods ◽

Litter Weight ◽

Heritability Estimates ◽

Synthetic Line

SUMMARYData on 902 ewes (1755 records) bom over 7 years in the synthetic ABRO Dam Line were analysed by least squares. Reproductive traits of the ewe were not affected by whether she was a single or a twin or by the age of her dam. Ewe age had major effects on all reproductive traits. Litter weight traits were affected by the sex distribution and the age of the litter when weighed.Heritability estimates, both by half sib and regression methods, were low for litter size, low to moderate for litter weights, and higher for ewe and fleece weights. Genetic correlations among the litter-weight traits were high. Together with the heritability estimates, they indicated that selection on litter weight at birth (and perhaps other traits) might give a greater change in total litter weight at weaning, the main measure of ewe productivity and the objective in improvement, than would direct selection.

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