The Effect of Age, Body Height, Weight, Testosterone Hormone Concentration and Semen Quality on the Libido Level of Pesisir Cattle

| This research was conducted in two stages to determine the superior criteria characteristics of Pesisir cattle, required for high intensity mating, using 9 cows and 15 bulls. The first stage involves the selection based on age, height, weight, Body Condition Score (BCS), and reproductive diseases. Also, cows were examined for pregnancy and heat, while bulls were evaluated for scrotal boundary, testosterone, and semen quality. Furthermore, the second stage comprise of bulls response assessment to aggressiveness and libido. The results showed a characteristic age range of 18-24 months for cows, and 24-48 months for bulls, with a height of 129.77±1.30cm and 124.33±11.10cm, alongside weight of 256.66±38.28kg and 250.93±87.43kg, respectively. In addition, the BCS were 3-4 and 4-5, correspondingly, and all cows are not pregnant with three heat, three silent heat, and three not experiencing heat. Conversely, the scrotal boundary of bull was 25.30±6.75cm, with testosterone measuring 9.63±5.25ng/ml, alongside good semen quality observed in 11 and bad in 4. The results of the second stage show all bulls to be aggressive towards heat and silent heat, but less aggressive toward non-heat cows. In addition, the libido level was significantly affected by testosterone and age (P<0.01), alongside height, weight, and semen quality (P<0.05). However, the main contributing factors were determined as testosterone concentration, age, weight, semen quality, and height. In conclusion, the high intensity mating criteria for bulls were ages 36-48 months, height 134±1.73cm, weight 348±31.18kg, scrotal boundary 32±0.87cm, testosterone 12.62±3.77ng/ml and good semen quality.


INTRODUCTION
P esisir cows belong to a cattle family separate from other natives or local Indonesian livestock, due to the varied characteristics. There is a significant increase in production with the supply of high quality breeds at the Superior Livestock Breeding and Animal Feed Center (SLBAFC), Padang Mangatas. This is attained through the deployment of management strategies, in an attempt to maximize pasture rotation and other forms of grazing. Furthermore, a natural mating process introduces a superior male with high reproductive potential to fertilize a group of 180 adult cows in 2 months.
Based on the decree of the Minister of Agriculture No. 2908 / Kpts / OT.140 / 6/2011 dated 17 June 2011, the Pesisir cattle demonstrate distinctive characteristic of a brick-red dominant body color varying between yellow, In addition, there are no criteria for the selection of superior bulls for the purpose of mating in the past, and reproductive failure reaches 20%, because of low copulating ability. Meanwhile, sexual impulse is influenced by the level of libido (Ashwood, 2009), therefore bulls with high drive tend to produce a greater number of viable semenatozoa through repeated ejaculation in a relatively short time (Rehman et al., 2016). Evaluation superior bull for the purpose of mating based on results of the libido effect levels on age, height, weight, testosterone concentration, and semen quality.
The bull age significantly affects semen quality improvement, which reduces after a certain period (Mahmood et al., 2014). Also, the semen quality at certain period gradually decreases after 100 weeks with the tendency to further increase above 300 weeks (Nyuwita, 2015). semenatogenesis and bull fertility depending on the availability of testosterone, and meiosis is not attainable without this hormone (William, 2011). In addition, concentrated quanitities influence libido level to various extent, depeding on the individual species (Mahmood et al., 2013).
However, SNI 7651.6: 2015 only determines the minimum requirements of the breeders without complementing the criteria for high reproductive abilities, and hence does not guarantee successful selection during natural mating. This prompts the need for an investigation to determine the selection criteria for active bulls by analyzing several factors affecting libido levels, including age, height, weight, testosterone concentration and semen quality.

MATERIALS AND METHODS
This research was conducted at Superior Livestock Breeding and Animal Feed Center (SLBAFC), Padang Mangatas, using Pesisir cattle, comprising 9 cows (three heat, three silent heat, three non-heat), and 15 bulls. However, the Pesisir cattle originated from Pesisir Selatan Regency, Sumatera Barat province known to have been developed at SLBAFC, Padang Mangatas. The process was divided into two stages, termed selection of specimen (stage I) and assessment of libido level (stage II).

StaGe I, SelectIon of cowS and BullS
The cattle were examined to ascertain physical and reproductive status. Therefore, the physical test determines age, height, chest circumference, body weight, body condition score (BCS), and scrotal boundary. The results showed the criteria for estimating BCS with values ranging from 1 -5, where BCS 1 was observed to be thin, with visible bones, and without fat. Moreover, BCS 2 appeared thin with clear upper bones, and little flesh added at the base of the tail, while BCS 3 represented obvious ribs, slight hip protrusions, and fat formed at the shoulders and chest. BCS 4 showed the bone structure was difficult to recognize, due to the deposit behind and above the shoulder, the base of the tail, and chest. BCS 5 animals were observed without visible bones ( Juandhi, et al., 2019). The scrotal size is used to determine age and reproductive ability. Therefore, this factor is recognized as one of the most accurate indicators for male puberty determination. Males with large scrotal boundary exhibit a high tendency to rapidly approach young age (Yelich, 2008).
The screening for the reproductive status for both species showed negative values for Brucellosis, Infectious Bovine Rhinotracheitis (IBR), Bovine Viral Diarrhea (BVD), ParaTuberculosis (ParaTB), Bovine Genital Campylobacteriosis (BGC), Enzootic Bovine Leucosis (EBL), Trichoniosis and Leptospirosis (Bahri and Martindah, 2005). Subsequently, pregnancy and heat tests were conducted by observing the symptoms and follicular development (dominant/not dominant) through rectal palpation of the uterus and ovaries (Waluyo, 2014). According to Pamungkas et al. (2015) follicular development can be analyzed with the use of transrectal ultrasonography. Therefore, the presence of a massive dominant follicle followed by signs of heat, illustrates that it has developed into a de Graaf follicle, however, when it is not followed by signs of heat, it is categorized as a cow in a state of silent heat. In addition, cows without clear signs of heat and no dominant follicle are classified as not in heat. Balumbi et al. (2019), stated that the production of large follicles and high estrogen, indicates that the heat quality is good. One of the common signs of heat is the production of clear mucus.
The examination of Brucellosis was conducted using Rose Bengal Plate test (RBPT) and confirmed by complement fixation test (CFT), while Infectious Bovine Rhinotracheitis (IBR), Enzootic Bovine Leucosis (EBL), Bovine Viral Diarrhae (BVD), and paratuberculosis were analyzed by enzyme-linked immunosorbent assay (ELISA). Scanning for leptospirosis through the microscopic agglutination test (MAT), while investigating for campylobacteriosis is performed through isolation and identification of bacteria from vaginal swab samples. The detection of trichomoniasis blood parasites is carried out by examining a blood smear.
The dominant follicle in the ovary was determined through rectal palpation as the one with a larger size (Budiyanto, et al., 2015). Measuring follicular diameter with transrectal ultrasonography ranges from 6 -11 mm. This diameter range is a category of ovulating follicular in Pesisir cattle (Zaituni et al., 2017). Locating the dominant follicle and the presence of heat sign indicates the cows are in estrus. This signal is only observed once during the selection of cows from the grazing field, and is also applied to test libido level. Further observation of heat symptoms includes swollen vulva, thick mucus, restlessness, and heat period (Yousuf et al., 2015).
The examination the fresh semen quality was performed macroscopically and microscopically. Macroscopic provision includes: 1) Measuring pH by placing cement on litmus paper. 2) Visually observing the color after holding, as good cement appears beige; 3) Consistency is determined by simply tilting the collection tube and then straightening it back up. The cement drops slowly to indicate high concentration, while a fast release shows the concentration is low. Microscopic examination includes: 1) Individual motility is observed on the motion of the semenatozoa using a microscope with 400x magnification. The motility criteria for semenatozoa are as follows: 0%: immotile semenatozoa are immobile; 50%: semenatozoa move in a circle, less than 50% are progressively and also not wavy; 50-80%: semenatozoa move gradually and produce mass movement; 90%: progressive motion is agile and forms waves; 100%: very progressive and also shows fast waves; 2) Viability and abnormality of semenatozoa, was observed based on differential staining using eosin nigrosin dye. The preparations were achieved under a 400x magnification light microscope. When the preparation is activated, it tends to show white coloration, while dead semenatozoa extends to red due to absorbed eosin color. Furthermore, the number of live and dead semenatozoa is counted from 200 semenatozoa cells. 3) Concentration of semenatozoa are evaluated using haemocytometer pipette and a Neubauer counting chamber. The cement was sucked up to a scale of 0.5 and then mixed with 3% NaCl. Subsequently, the solution was agitated for 2-3 minutes to form a homogenous composition. Then, the sample was observed in a Neubauer counting chamber with a light microscope of 400x magnification. The calculation of semenatozoa concentration in the number of rooms are counted as five boxes with 80 small rooms multiplied by 10 per milliliter (Indriani et al., 2013)

StaGe II, lIBIdo level aSSeSSment
This test commenced by evaluating the aggressive response of bulls to cows, continued by further investigating the factors affecting libido, in an attempt to determine the criteria of superior bulls with high mating intensity.

aGGreSSIve reSPonSe teSt BullS to cowS
This was a descriptive evaluation, where the aggressive response of bulls to heat cows, silent heat, and non-heat were examined. Subsequent observations were based on the behavior, starting from the approach or teasers, and insufflating is part of the sexual displays performed by the bulls prior to mating. This is followed by attempts to mount without being accompanied by copulation (Achmad, et al., 2017). The aggressive response assessment initially involved the introduction of 3 selected heat cows into a loose cage (rench). A rench is a loose enclosure surrounded by a fence with an estimated area of 30 x 9 M2, and is also equipped with a floor for feeding and drinking (Affandhy et al., 2007). Next, the bulls were consecutively studied, and the aggressive response towards 3 silent heat cows and 3 non-heat cows was analyzed. Table 1 shows each behavior, assigned a score after a 5 minutes observation period (Walker, 2009).

Journal of Animal Health and Production
January 2021 | Volume 9 | Issue 1 | Page 81

factorS teSt that affectS lIBIdo
The assessment involved investigating the effects of age, height, weight, testosterone concentration, and semen quality on libido.

data analySIS
The generated data were analyzed through cross-tabulation to evaluate the libido level, while Spearman's correlation was employed to ascertain the factors affecting libido. Statistical analysis was conducted with the Statistical Package for Social Science (SPSS) for Windows version 16.

StaGe I, SelectIon of cowS and BullS
Physical Examination Results of Cows and Bulls This examination was performed to determine the effect of age, height, weight, and BCS on the reproduction and heat status of cows. Table 2 showed higher values, exceeding the minimum standard requirements according to SNI 7651.6: 2015 and Minister of Agriculture Decree No. 2908/Kpts/ OT.140/6/2011. This indicates the pasture rotation -grazing system was well maintained and the tendency for high quality selection and bull replacement in certain periods to improve Pesisir cattle performance. This opinion as supported by Brantly (2013), where the management strategies utilized reportedly possessed the potential to maximize livestock growth, resulting from sufficient feeding from tastier and more nutritious forage leaves. The determination of suitable feed is achieved using palatability test, known as the degree of preference for certain foods served to livestock. However, there is a need to substitute the bulls every third calves to avoid inbreeding. The bulls are replaced or abandoned after natural mating until the cows calves three times. Table 3 shows the screening, performed to ascertain the reproductive disease-free status assumed to influence the heat cycle in cows, and also the libido levels in bulls.   Table 3. showed negative values for 9 cows and 15 bulls selected after testing in accordance with the animal health development strategic plan, Directorate of Animal Health, Directorate General Livestock and Animal Health, Ministry of Agriculture. Furthermore, Brucellosis, IBR, BVD, BGC, PataTB, EBL, Trichomoniasis and Leptospirosis are infectious animal diseases forbidden in livestock breeds (Bahri and Martindah, 2005). Table 4 shows the cow selection requirements including physical examination, reproductive pregnancy and heat status, among others.

Journal of Animal Health and Production
January 2021 | Volume 9 | Issue 1 | Page 82   follicular phases, resulting in three symptoms of heat, nonheat and silent heat, while a total of three were in the luteal phase. According to Waluyo (2014), these symptoms are affected by the production of estrogen hormone by ovaries. Furthermore, there is an increase in estrogen levels at the final phase of maturity of de Graaf follicles. This promotes receptiveness and heat symptoms, including the appearance of swollen and reddish vagina and vulva, several clear and transparent cervix mucus, and vagina flow. Also, heat symptoms are not very obvious in young (newly puberty) or adult cows with several calves.

BullS SelectIon
Besides the physical examination, Table 5 shows the two determinant criteria for high intensity superior mating needed to examine the reproductive status. These include testosterone concentration and semen quality.

Journal of Animal Health and Production
January 2021 | Volume 9 | Issue 1 | Page 83  Table 5 compares the average value of testosterone concentration in Pesisir bulls with Cholistani AI, crossbred Karan Fries, and Kuantan. The result shows Pesisir as a superior breed, with semen quality of 11 in the good and 4 in bad categories, alongside a minimum of 50% semen motility (SNI 4869.1: 2017).
Testosterone is an androgen in the testes, responsible for supporting semenatogenesis. The main function is to maintain the blood barrier testes, bond Sertoli-semenatids, and release adult semen (William, 2011). Noakes, et al. (2016 reported on the need for testosterone in semen production and subsequent maturity in the epididymis. This hormone has also been implicated in semen quality. Table 6 shows the aggressive response of bulls to heat, silent heat, and non-heat in cows. Table 6 shows the Cross-tabulation test analysis, and the results indicate aggression conditions of bull libido towards heat and silent heat, but less to non-heat. Furthermore, the response by percentage to heat is 20% high, 60% medium, and 20% low, while to silent heat was 26.7% moderate and 73.7% low, and non-heat was 100% low. Therefore, bulls with lower aggressive response to heat, silent heat and nonheat likely result from the different amounts of pheromone hormone stimulation issued in each heat status. Achmad, et al. (2017) affiliated the desire of bulls to mount cows with the stimuli received from sight, smell, touch, and hearing senses. In addition, there is a higher tendency for aggressiveness, when the cows experience a combination of heat responsible for the emission of fluid and odor pheromones. Baliarti et al. (2019) also corroborates the higher ability for bulls to naturally exhibit different attitudes towards the cycle and behavioral expressions during heat in cows. This is influenced by the chemical compounds or pheromones produced, indicating the entry into heating phase. Therefore, bulls capture specific odor, and is assumed to be stimulated by the appearance of sexual signs behavior.      Table 7 shows the analysis results of factors influencing the libido level. These include age, height, weight, testosterone concentration, and semen quality.

Results of Assessment Bulls Aggressive Response to Cows
The analysis results showed a very significant effect of age and testosterone concentration at (P<0.01) on libido levels, while the influence of height, weight, and semen quality were at (P<0.05). Furthermore, a strong correlation of (0.80-1.00) exists between testosterone concentration and libido levels, while age, weight, and semen quality was (0.60-0.79). However, height had a moderate correlation at (0.40-0.59). Table 8 shows the bull libido level towards cows, with respect to age groups of 24, 30, 36, and 48 months. Table 8 shows the increase in height, weight, testosterone concentration, and semen quality, alongside age from 24 to 48 months. Furthermore, the assessment reveals increased libido at 24 to 36 months and reduction at 48 months due to the decrease in semen motility by 63.33 ± 12.58%. The response towards heat was high aggressiveness at 36, moderate at 30 and 48, and low at 24 months. The outcome towards silent heat was moderate at 36 months while other ages were low, with non-heat prompting overall low aggressiveness. This is almost similar to the opinion of Ahmad et al. (2005), where age showed a significant effect on libido. Adult males aged 3-5, demonstrates the best libido compared to younger males under 3, and their older counterpart over 5 years. Table 7 and Table 8 indicates several factors influencing libido level, with testosterone concentration as the first and strongest. Chenoweth (1994), Mahmood et al. (2013), andSyarifuddin et al. (2017), affirmed blood hormone concentration and testosterone as an alternative and indirect

Journal of Animal Health and Production
January 2021 | Volume 9 | Issue 1 | Page 85 assessment procedure for determining libido. Therefore, cattle libido level is affected by testosterone concentration. The second is age. Chenoweth (1994) and Ahmad et al. (2005) posited age impacts libido level and sexual behavior character. An increase in libido is apparent at 16-31 months. Achmad et al. (2017) also asserted the influence on animal libido in is from outside or inside the body. The ability to mount a bull is age based, and older age causes progressively malfunctioning limbs from dislocations/ fractures and hind or spine osteoarthritis. Petherick's (2005) confirmed greater libido expression and serving efficiency in older bulls which is likely to signifybetter sexual experience.
The third factor affecting bulls libido level is body weight. Dalimunthe et al. (2017) postulated a higher total amount of PGF2α from bodyweight. Furthermore, the PGF2α concentration is proportionate to androgen hormones including testosterone. The endocrine system development with the animal puberty process impacts libido level.
The fourth factor is semen quality level. William (2011), expressed an impact on semen quality from testosterone concentration. Therefore, good semen quality and adequate hormone testosterone concentration affects libido level.
Height is the fifth factor. Walker et al. (2009) confirmed physical abilities, dominated by the bulls body size, facilitates successful breeding and ability to mate Sumardani et al. (2017) also supported the significant impact of physique higher dimensions on reproductive performance. Table 9 shows the criteria for superior bulls with high intensity mating and the value of aggressiveness. This is based on the analysis data on response of bulls to cows in Table 6. Table 9 shows the bulls high aggressiveness response to cows, indicated in codes B1, B4, and B5 cattle. The criteria guidelines selected to determine superior bulls with characteristic high mating intensity includes age, height, chest circumference, weight, scrotal boundary circumference, testosterone concentration, and semen quality. Table 10 shows the results of criteria to determine superior bulls with high intensity mating to cows. Table 10 shows higher values for age, height, chest circumference, and scrotal boundary circumference in the criteria for superior bulls with high intensity mating, compared to the minimum standard according to SNI 7651.6: 2015. Furthermore, the quality of semen is of good value according to SNI 4869.1: 2017. There is also an additional requirement of testosterone concentration at 12.62 ± 3.77ng/ml

CONCLUSION
All bulls are aggressive to heat and silent heat, but less aggressive to non-heat cows. The percentage aggressiveness response towards heat was 20% high, 60% moderate, and 20% low, while, silent heat was 26.7% moderate and 73.7% low, and non-heat was 100% low. The age and testosterone substantially impacted on libido level at (P<0.01), while height, weight, semen quality were significant at (P<0.05). The libido level strongly correlated with testosterone concentration at (0.80-1.00), while age, weight, and semen quality was significant at (0.60-0.79). However, height showed a moderate relationship at (0.40-0.59).
Progressive age instigates an increase in libido level, and the highest value is observed at 36 months, although a decline was recorded on the 48 month.
The major influencing factors include the hormone testosterone, followed by age, weight, semen quality and height The criteria of Pesisir superior bull with high intensity mating include age 36-48 months, height 134±1.73cm, chest circumference 161±1.73, weight 348±31.18kg, scrotal boundary 32±0.87cm, testosterone concentration 12.62±3.77ng/ml and good semen quality.