The objectives of this experiment were to investigate the effects of supplementation of four types of medicinal herbs on some rumen fluid parameters, fermentation gas production, activities of rumen bacteria, blood constituents of bucks and productive performance of does. Fifteen mature healthy goat bucks averaged 44.75 ± 3.6 kg live body weight and 33 months of age were divided into five similar groups (3 animals each). Another 5 experimental groups of does (7 does each) with an average live body weight of 56.38 ± 4.3 Kg were also used. All groups were fed similar basal diet consisted of 60% concentrate feed mixture (CFM) and 40% berseem hay (BH) on DM basis. Bucks and does in the 1^st group was fed on basal diet without supplementation (control), while CFM in diets of the 2^nd, 3^rd, 4^th and 5^th groups were supplemented with 1 g/10 kg LBW, of Ginger powder (Zingiber officinale, L.) ZIN,Curcumin or Turmeric powder (Curcuma longa) CUR, Oregano leaves crushed (Origanum vulgare, L.) ORI or crushed (Nigella sativa, L. seeds) NSS. Results showed that all the tested feed additives, except ORI one, were significantly (P<0.01) increased pH values of rumen fluid in comparison with that of control that free from the additives. The highest values of VFA were obtained with groups received either ZIN or ORI followed by that from NSS group with insignificant differences between them and control one. Other with CUR-ration had significant lower total VFA value than that of control one. The supplementation with ORI produced the highest (P<0.01) NH₃-N value compared to those of NSS, ZIN, CUR and control groups. Also, the values of ZIN, CUR and NSS regarding NH₃-N were significant higher than that of control. The addition of CUR produced the highest value of in vitro gases with proteolytic bacteria and NSS gave the highest one with cellulolytic bacteria, while ZIN recorded the highest gas with amylolytic bacteria without significant differences for all. Differences among treatments in terms of Deoxy ribonucleic acid (DNA), Ribonucleic acid (RNA) and Olego nucleotide (ON) were not significant. The group received ZIN had the highest values for proteolytic, cellulolytic and amylolytic bacterial groups compared to the control ones or those received CUR, ORI or NSS ones. Animals received ORI gave the lowest significant (P<0.01) values of all studied blood constituents among the values of all experimental dietary treatments. Does in the experimental groups showed that supplementation improved and maintained their body weight from starting of the experiment at the last third of pregnancy period till after kidding with superiority for CUR, ORI and NSS over that recorded for ZIN and control groups. As for average total milk production during suckling period NSS group produced the highest value followed by ORI, CUR and ZIN compared to the control ones which produced the lowest average. Meanwhile, kids average birth weight was higher in NSS group followed by those of ORI, CUR and ZIN, respectively compared to that in the control group. On the other hand, kids of the control group and ORI ones attained more weaning weight than those of the other 3 groups although the average daily body weight gain of kids in the control group during the 90 days of suckling (g/h/d) was the lowest value. It can be concluded that the use of herbs as feed additives in a descending order (NSS followed by ORI, CUR and ZIN) according to the results obtained herein can participate in enhancing animal productivity, health and reducing the energy which can be lost from other feed constituents.