Fertility of Broiler Breeders Following Categorization by the OptiBreed® Sperm Quality Index When Hens Are Inseminated with a Constant Number of Sperm

Abstract

If semen quality was known prior to insemination, sperm doses could possibly be decreased, maximizing the number of hens inseminated. The sperm quality index (SQI), an indicator of overall semen quality, is determined by the number of deflections in a light path due to sperm movement inside a capillary tube. The objectives of this study were 1) to determine the age at which the SQI becomes a static predictor of semen quality and 2) to determine if fertility of males with a higher SQI responds more favorably to insemination dose reduction than that of males with a lower SQI. Weekly from 23 to 32 wk of age, 144 Cobb males were tested for SQI. At 32 wk of age, males were placed into four groups that represented the SQI population quartiles as follows: poor, fair, good, and best. A fifth SQI group, uncategorized, was created to determine fertility of the original population by mixing equal amounts of semen from each of the four groups. Semen was collected weekly from 33 to 40 wk of age from 18 males in each of the four groups, pooled by group, and used to inseminate 30 hens per group with 50 or 100 million sperm. Eggs were collected daily, incubated, and broken out to determine fertility. Correlation coefficients between weekly SQI results and overall averages for individual males indicated that the SQI stabilized after the birds were 28 wk of age. The main effect for SQI selection revealed that the best SQI group had the highest fertility (88%), which did not differ from the good (83%) or fair group (82%) but was greater than the uncategorized group (80%). Fertilities of the top three groups and the uncategorized group were higher than the poor group (63%) (P< 0.0001, SEM 2.18). In addition, there was an interaction between SQI classification and insemination dose. Fertilities of the top three SQI groups were similar at the 50 and 100 million sperm doses. However, the poor and uncategorized SQI groups had lower fertility at the 50 million dose as compared to the 100 million dose. By categorizing males into SQI groups after 28 wk of age, insemination dose can be reduced, maximizing a male's fertilizing potential.

Inheritance of fertility in broiler chickens

“…The contributions from permanent environment effects in both sexes increased with age, particularly for males (Figures 2 and 3) and were much larger than those from the genetic effects, but the correlations across ages were much lower. This pattern agrees with a finding that males having a poor sperm quality index at a young age have a low sperm quality subsequently and a large decline in fertility after the peak [28]. …”

The effects of heat stress and sperm quality classification on broiler breeder male fertility and semen ion concentrations

“…Overall heat mortality data were analysed using a t-test. Parker et al (2002) as well as the present study (Table 2) revealed that fertility is similar among males of the top 75% of the SQI population (B, G, and F groups) but much greater than that of males in the lower 25% of the SQI population (P group). Therefore, linear contrasts were used to compare the response of males in the top 75% (B+G+F) and in the lowest 25% (P) of the SQI population to heat stress (Steel and Torrie, 1980).…”

“…An asterisk indicates a signi cant difference between control and heat stressed males for a given week. SQI values produced a greater proportion of fertilised eggs in the current study, as in past research (McDaniel et al, 1998;Parker et al, 2000Parker et al, , 2002. However, in the present study, males with higher SQI values were more affected by high temperature than males with lower values.…”

“…Also, it is hypothesised that the severity of heat stress infertility may depend upon a male's semen quality or SQI prior to heat stress. Parker et al (2002) have already shown that, in a thermoneutral environment, fertility is very similar along males of the top 75% of the SQI population but much greater than that of males in the lower 25% of the SQI population. The present study was undertaken to determine the effects of heat stress on fertility, semen quality, and semen ion concentrations in males classi ed for the SQI prior to heat stress.…”

Inheritance of the duration of fertility in chickens and its correlation with laying performance

“…The effect of sperm quality on DF has been clearly demonstrated by Brillard et al [ 25 ]. To circumvent any undesirable effects of differences in semen quality on subsequent fertility [ 29 ], the spermatozoa concentration and motility for each male were assessed with a light microscope. Only males with 3 to 5 billion sperm per milliliter of semen were used for this insemination experiment.…”