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A 30-kDa heparin-binding protein named fertility-associated antigen (FAA) was identified in sperm membranes of beef bulls with greater fertility potential. In a survey of 2,191 beef bulls, 88% had FAA present in sperm membranes (FAA-positive), and 12% were FAA-negative. In the first study, 54 Santa Gertrudis and 51 Santa Cruz bulls were grouped (1 to 14 bulls per group) according to FAA profiles and were bred to 2,403 cows at ratios of I bull: 25 cows. Fertility for 14 groups of FAA-positive bulls averaged 88%, whereas three groups of FAA-negative bulls impregnated 79% of the cows. Thus, FAA-positive bulls were nine percentage points more (P < .01) fertile than FAA-negative bulls. In the second study, 2-yr-old Santa Cruz bulls (n = 26) were grouped according to FAA profiles and serving capacity. The fertility of the group of 12 high-serving-capacity, FAA-positive bulls was 87% of 270 cows. The group of six FAA-negative bulls with high serving capacity impregnated 78% of 143 cows. Among the groups of bulls with high serving capacity, FAA-positive bulls were nine percentage points more (P < .05) fertile than FAA-negative bulls. The group of eight FAA-positive bulls with low serving capacity impregnated the least (P < .01) percentage (69%) of 238 cows. Serving capacity of bulls should be considered when optimizing fertility potential. Among bulls with acceptable physical characteristics and serving capacity, determination of FAA profiles in sperm can be used as a tool to identify subfertile bulls. Key Words: Bulls, Fertility, Proteins, Spermatozoa

A monoclonal antibody (M1) was produced against seminal fluid heparin-binding proteins (HBP) from a vasectomized bull. In the first part of this study, the presence of HBP in sperm or seminal fluid was determined for 53 bulls with an ELISA using M1. Bulls (8 to 18 per pasture) were bred to 1,114 cows at ratios of 1 bull:25 cows. Bulls with detectable HBP on sperm membranes were 11 percentage points more fertile than bulls with undetectable HBP in sperm membranes. In the second part of this study, three sperm membrane HBP approximately 30, 24, and 21.5 kDa were identified with Western blots using M1. Santa Gertrudis bulls (n = 64) were bred to 1,354 Santa Gertrudis cows in groups with 2 to 11 bulls. Bulls with those three HBP (Group A) or a single 30-kDa HBP (Group B) in sperm membranes had the greatest fertility, ranging from 74.4 to 89.9% (mean = 81.5%) of the palpated cows that were pregnant. Bulls with the 21.5- and 30-kDa HBP (i.e., the 24-kDa HBP was absent; Group C) had a reduced fertility of 61.3%. Bulls without detectable HBP (Group D) resulted in 41.9% of 186 cows palpated pregnant. Bulls in Groups A and B were more (P < .01) fertile than all other groups. In conclusion, the presence of HBP in sperm membranes was indicative of the fertility potential of bulls. Key Words: Bulls, Fertility, Heparin-Binding Proteins, Spermatozoa, Monoclonal Antibodies

Background: Traumatic brain injury (TBI) commonly elicits acute (APTH) and/or persistent (PPTH) post-traumatic headache. Calcitonin gene related peptide (CGRP) has been implicated as a contributor to PTH pathophysiology. We explored the possibility of sexual dimorphism in the effects of CGRP receptor (CGRP-R) blockade in a preclinical model of PTH induced by a mild TBI (mTBI) in male or female mice. Methods: Mice were lightly anesthetized and placed on a tissue paper stage prior to receiving a sham procedure or mTBI resulting from a closed-head weight drop injury. Behavioral responses to periorbital and hindpaw tactile (von Frey filaments) or thermal (hot plate) stimuli over the first 14 days post-mTBI were evaluated as measures of APTH. The PPTH phase was studied following the resolution of mTBI-induced APTH at days 14 and 28. PPTH was precipitated by exposure to bright lights (i.e., bright light stress, BLS). Olcegepant was delivered subcutaneously either repeatedly beginning 2 h after mTBI to produce a sustained block of CGRP-R signaling across the APTH phase, or as a single administration on days 14 or 28 post-mTBI to evaluate possible effects during the PPTH phase. Results: mTBI, but not sham-procedure, produced periorbital and hindpaw tactile allodynia, as well as thermal hypersensitivity in mice of both sexes. APTH-related hypersensitivity was transient and resolved by day 14 post-injury. No sex differences were observed in the magnitude or duration of APTH-related pain behaviors. Sustained CGRP-R blockade was, however, significantly more effective in female than male mice in inhibiting pain behaviors in the APTH phase and in preventing the emergence of BLS-induced PPTH. CGRP-R blockade following the resolution of mTBI-induced APTH pain behaviors, on either day 14 or 28, minimally altered BLS-induced PPTH in either sex. Conclusions: Sustained CGRP-R blockade starting soon after mTBI significantly inhibited APTH and prevented the expression of PPTH with greater analgesic effects in females compared to males. Delayed CGRP-R blockade beginning after resolution of APTH phase was minimally effective in preventing expression of PPTH in either sex. These data are consistent with previous observations that CGRP induces pain behaviors preferentially in females. Early and continuous CGRP blockade following mTBI may represent a viable treatment option for PTH treatment and the prevention of PTH persistence, especially in females. [ABSTRACT FROM AUTHOR]